Phosphodiesterase inhibition mediates matrix metalloproteinase activity and the level of collagen degradation fragments in a liver fibrosis ex vivo rat model

Directory of Open Access Journals (Sweden)

Veidal Sanne Skovgård

2012-12-01

Full Text Available Abstract Background Accumulation of extracellular matrix (ECM and increased matrix metalloproteinase (MMP activity are hallmarks of liver fibrosis. The aim of the present study was to develop a model of liver fibrosis combining ex vivo tissue culture of livers from CCl4 treated animals with an ELISA detecting a fragment of type III collagen generated in vitro by MMP-9 (C3M, known to be associated with liver fibrosis and to investigate cAMP modulation of MMP activity and liver tissue turnover in this model. Findings In vivo: Rats were treated for 8 weeks with CCl4/Intralipid. Liver slices were cultured for 48 hours. Levels of C3M were determined in the supernatants of slices cultured without treatment, treated with GM6001 (positive control or treated with IBMX (phosphodiesterase inhibitor. Enzymatic activity of MMP-2 and MMP-9 were studied by gelatin zymography. Ex vivo: The levels of serum C3M increased 77% in the CCl4-treated rats at week 8 (p 4-treated animals had highly increased MMP-9, but not MMP-2 activity, compared to slices derived from control animals. Conclusions We have combined an ex vivo model of liver fibrosis with measurement of a biochemical marker of collagen degradation in the condition medium. This technology may be used to evaluate the molecular process leading to structural fibrotic changes, as collagen species are the predominant structural part of fibrosis. These data suggest that modulation of cAMP may play a role in regulation of collagen degradation associated with liver fibrosis.

In vivo detection of c-MET expression in a rat hepatocarcinogenesis model using molecularly targeted magnetic resonance imaging.

Science.gov (United States)

Towner, Rheal A; Smith, Nataliya; Tesiram, Yasvir A; Abbott, Andrew; Saunders, Debbie; Blindauer, Rebecca; Herlea, Oana; Silasi-Mansat, Robert; Lupu, Florea

2007-01-01

The multifunctional growth factor scatter factor/hepatocyte growth factor and its tyrosine kinase receptor, c-MET, have been implicated in the genesis and malignant progression of numerous human malignancies, including hepatocellular carcinomas. The incidence of hepatocellular carcinomas in the United States has increased noticeably over the past two decades and is listed as the fifth major cancer in men worldwide. In this study, we used a choline-deficient l-amino acid (CDAA)-defined rat hepatocarcinogenesis model to visualize increased in vivo expression of the c-MET antigen in neoplastic lesion formation with the use of a super paramagnetic iron oxide (SPIO)-anti-c-MET molecularly targeted magnetic resonance imaging (MRI) contrast agent. SPIO-anti-c-MET was used for the first time to detect overexpression of c-MET in neoplastic nodules and tumors within the livers of CDAA-treated rats, as determined by a decrease in MRI signal intensity and a decrease in regional T(2) values. Specificity for the binding of the molecularly targeted anti-c-MET contrast agent was determined using rat hepatoma (H4-II-E-C3) cell cultures and immunofluorescence microscopic imaging of the targeting agents within neoplastic liver tissue 1 to 2 hours following intravenous administration of SPIO-anti-c-MET and MRI investigation. This method has the ability to visualize in vivo the overexpression of c-MET at early developmental stages of tumor formation.

Dual-energy X-ray absorptiometry underestimates in vivo lumbar spine bone mineral density in overweight rats.

Science.gov (United States)

Cherif, Rim; Vico, Laurence; Laroche, Norbert; Sakly, Mohsen; Attia, Nebil; Lavet, Cedric

2018-01-01

Dual-energy X-ray absorptiometry (DXA) is currently the most widely used technique for measuring areal bone mineral density (BMD). However, several studies have shown inaccuracy, with either overestimation or underestimation of DXA BMD measurements in the case of overweight or obese individuals. We have designed an overweight rat model based on junk food to compare the effect of obesity on in vivo and ex vivo BMD and bone mineral content measurements. Thirty-eight 6-month old male rats were given a chow diet (n = 13) or a high fat and sucrose diet (n = 25), with the calorie amount being kept the same in the two groups, for 19 weeks. L1 BMD, L1 bone mineral content, amount of abdominal fat, and amount of abdominal lean were obtained from in vivo DXA scan. Ex vivo L1 BMD was also measured. A difference between in vivo and ex vivo DXA BMD measurements (P body weight, perirenal fat, abdominal fat, and abdominal lean. Multiple linear regression analysis shows that body weight, abdominal fat, and abdominal lean were independently related to ex vivo BMD. DXA underestimated lumbar in vivo BMD in overweight rats, and this measurement error is related to body weight and abdominal fat. Therefore, caution must be used when one is interpreting BMD among overweight and obese individuals.

An acute rat in vivo screening model to predict compounds that alter blood glucose and/or insulin regulation.

Science.gov (United States)

Brott, David A; Diamond, Melody; Campbell, Pam; Zuvich, Andy; Cheatham, Letitia; Bentley, Patricia; Gorko, Mary Ann; Fikes, James; Saye, JoAnne

2013-01-01

Drug-induced glucose dysregulation and insulin resistance have been associated with weight gain and potential induction and/or exacerbation of diabetes mellitus in the clinic suggesting they may be safety biomarkers when developing antipsychotics. Glucose and insulin have also been suggested as potential efficacy biomarkers for some oncology compounds. The objective of this study was to qualify a medium throughput rat in vivo acute Intravenous Glucose Tolerance Test (IVGTT) for predicting compounds that will induce altered blood glucose and/or insulin levels. Acute and sub-chronic studies were performed to qualify an acute IVGTT model. Double cannulated male rats (Han-Wistar and Sprague-Dawley) were administered vehicle, olanzapine, aripiprazole or other compounds at t=-44min for acute studies and at time=-44min on the last day of dosing for sub-chronic studies, treated with dextrose (time=0min; i.v.) and blood collected using an automated Culex® system for glucose and insulin analysis (time=-45, -1, 2, 10, 15, 30, 45, 60, 75, 90, 120, 150 and 180min). Olanzapine significantly increased glucose and insulin area under the curve (AUC) values while aripiprazole AUC values were similar to control, in both acute and sub-chronic studies. All atypical antipsychotics evaluated were consistent with literature references of clinical weight gain. As efficacy biomarkers, insulin AUC but not glucose AUC values were increased with a compound known to have insulin growth factor-1 (IGF-1) activity, compared to control treatment. These studies qualified the medium throughput acute IVGTT model to more quickly screen compounds for 1) safety - the potential to elicit glucose dysregulation and/or insulin resistance and 2) efficacy - as a surrogate for compounds affecting the glucose and/or insulin regulatory pathways. These data demonstrate that the same in vivo rat model and assays can be used to predict both clinical safety and efficacy of compounds. © 2013.

Characterization and toxicological effects of three-dimensional graphene foams in rats in vivo

Energy Technology Data Exchange (ETDEWEB)

Zha, Yingying [University of Science and Technology of China, CAS Key laboratory of Brain Function and Diseases and School of Life Sciences (China); Chai, Renjie [Southeast University, Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences (China); Song, Qin [Chinese Academy of Sciences, Suzhou Institute of Nano-Tech and Nano-Bionics (China); Chen, Lin; Wang, Xinxing [University of Science and Technology of China, CAS Key laboratory of Brain Function and Diseases and School of Life Sciences (China); Cheng, Guosheng [Chinese Academy of Sciences, Suzhou Institute of Nano-Tech and Nano-Bionics (China); Tang, Mingliang, E-mail: mingliangtang@seu.edu.cn [Southeast University, Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences (China); Wang, Ming, E-mail: wming@ustc.edu.cn [University of Science and Technology of China, CAS Key laboratory of Brain Function and Diseases and School of Life Sciences (China)

2016-05-15

Current studies have demonstrated the advantage of graphene-based materials, which suggests their potential usage for biomedical applications. However, the in vivo toxicity and performance of three-dimensional (3D) graphene foams (GFs) remain largely unclear. In the present study, we identified the short-term and long-term tissue responses to GFs or graphene oxide foams (GOFs) in a rat model of subcutaneous implantation. Results from blood biochemistry, hematological analysis, histological examination, and behavioral test all indicated nearly no noticeable in vivo toxicity in either GF- or GOF-implanted rats during the first 2 weeks post-implantation. In addition, hematoxylin and eosin (H and E) stained images showed GFs or GOFs remained in the subcutaneous implantation site for at least 7 months without significant degradation after implantation. Our study demonstrates the non-biodegradable feature of GFs and GOFs as implanted scaffolds, while they exhibit good biocompatibility in vivo. It adds new evidence for the in vivo toxicological study of GFs and GOFs, which may provide reference for their biomedical applications.

In Vivo Detection of c-MET Expression in a Rat Hepatocarcinogenesis Model Using Molecularly Targeted Magnetic Resonance Imaging

Directory of Open Access Journals (Sweden)

Rheal A. Towner

2007-01-01

Full Text Available The multifunctional growth factor scatter factor/hepatocyte growth factor and its tyrosine kinase receptor, c-MET, have been implicated in the genesis and malignant progression of numerous human malignancies, including hepatocellular carcinomas. The incidence of hepatocellular carcinomas in the United States has increased noticeably over the past two decades and is listed as the fifth major cancer in men worldwide. In this study, we used a choline-deficient l-amino acid (CDAA-defined rat hepatocarcinogenesis model to visualize increased in vivo expression of the c-MET antigen in neoplastic lesion formation with the use of a super paramagnetic iron oxide (SPIO–anti-c-MET molecularly targeted magnetic resonance imaging (MRI contrast agent. SPIO–anti-c-MET was used for the first time to detect overexpression of c-MET in neoplastic nodules and tumors within the livers of CDAA-treated rats, as determined by a decrease in MRI signal intensity and a decrease in regional T2 values. Specificity for the binding of the molecularly targeted anti-c-MET contrast agent was determined using rat hepatoma (H4-II-E-C3 cell cultures and immunofluorescence microscopic imaging of the targeting agents within neoplastic liver tissue 1 to 2 hours following intravenous administration of SPIO–anti-c-MET and MRI investigation. This method has the ability to visualize in vivo the overexpression of c-MET at early developmental stages of tumor formation.

The rat subcutaneous air sac model. A new and simple method for in vivo screening of antiangiogenesis

International Nuclear Information System (INIS)

Lichtenberg, J.; Abildgaard Hansen, C.; Skak-Nielsen, T.; Bay, C.; Thing Mortensen, J.; Binderup, L.

1997-01-01

An experimental rat model, the Subcutaneous Air Sac (SAS) model, was developed to provide an animal model in which neo-vascularisation can be easily assessed in situ and quantified using a radiolabelled plasma marker. The SAS model was designed to replace a previous model where neo-vascularisation was induced by chemical injury of rat or rabbit cornea or by implantation of tumour cells intracorneally, a methodology which is believed to cause severe pain to the animals. In the SAS model the air sac replaces the cornea as a transparent avascular substratum in which vascularisation can be observed. The air sac is induced by injection of air subcutaneously on the back of the animal. After 8 to 10 days a sufficient air sac has been established. The animal is anaesthesized and by a minor operation the cellulose sponge is implanted upon the air sac under the skin. The vaso-proliferative effect of the cellulose sponge caused formation of new vessels which are macroscopically visible 10 days after implantation. The ability of the in vivo SAS model to show an anti-angiogenic effect of a systemically applied test compound was investigated using the fumagilline analogue TNP-470 (o-chloro-acetylcarbomoyl-fumagillol) as a positive control at dose levels of 0, 1, 2.5, 5 and 10 mg/kg/day given subcutaneously for 10 days. The neo-angio genesis was scored both in situ using a subjective point system and by measuring the 125 I-activity of the implant and the membrane after an intravenous injection of 125 I-labelled antibodies. The neo-angio genesis was reduced by approximately 45-50% in animals treated with 5 or 10 mg/kg/day of TNP-470 compared to animals treated with the vehicle. The animals treated with 10 mg/kg/day TNP-470 showed signs of toxicity. The SAS model is considered highly relevant for in vivo testing of potential anti-angiogenci drugs on humane grounds. The high reproducibility, the low cost and the technical simplicity of the method makes it attractive. (au)

Imaging regional metabolic changes in the ischemic rat heart in vivo using hyperpolarized(1-13C)Pyruvate

DEFF Research Database (Denmark)

Lauritzen, Mette Hauge; Magnusson, Peter; Laustsen, Christoffer

2017-01-01

in the in vivo rat heart in an open-chest model of ischemia reperfusion. Hyperpolarized MRI enables new possibilities for evaluating changes in cardiac metabolism noninvasively and in real time, which potentially could be used for research to evaluate new treatments and metabolic interventions for myocardial......We evaluated the use of hyperpolarized 13C magnetic resonance imaging (MRI) in an open-chest rat model of myocardial infarction to image regional changes in myocardial metabolism. In total, 10 rats were examined before and after 30 minutes of occlusion of the left anterior descending coronary...

Modeling the in vivo case with in vitro nanotoxicity data.

Science.gov (United States)

Shelley, Michael L; Wagner, Andrew J; Hussain, Saber M; Bleckmann, Charles

2008-01-01

As more in vitro nanotoxicity data appear in the literature, these findings must be translated to in vivo effects to define nanoparticle exposure risk. Physiologically based pharmacokinetic (PBPK) modeling has played a significant role in guiding and validating in vivo studies for molecular chemical exposure and can develop as a significant tool in guiding similar nanotoxicity studies. This study models the population dynamics of a single cell type within a specific tissue. It is the first attempt to model the in vitro effects of a nanoparticle exposure, in this case aluminum (80 nm) and its impact on a population of rat alveolar macrophages (Wagner et al. 2007, J. Phys. Chem. B 111:7353-7359). The model demonstrates how in vitro data can be used within a simulation setting of in vivo cell dynamics and suggests that PBPK models should be developed quickly to interpret nanotoxicity data, guide in vivo study design, and accelerate nanoparticle risk assessment.

An evaluation of in vivo models for toxicokinetics of hexavalent chromium in the stomach

Energy Technology Data Exchange (ETDEWEB)

Sasso, A.F., E-mail: sasso.alan@epa.gov; Schlosser, P.M., E-mail: schlosser.paul@epa.gov

2015-09-15

Hexavalent chromium (Cr6) is a drinking water contaminant that has been detected in most of the water systems throughout the United States. In 2-year drinking water bioassays, the National Toxicology Program (NTP) found clear evidence of carcinogenic activity in male and female rats and mice. Because reduction of Cr6 to trivalent chromium (Cr3) is an important detoxifying step in the gastrointestinal (GI) tract prior to systemic absorption, models have been developed to estimate the extent of reduction in humans and animals. The objective of this work was to use a revised model of ex vivo Cr6 reduction kinetics in gastric juice to analyze the potential reduction kinetics under in vivo conditions for mice, rats and humans. A published physiologically-based pharmacokinetic (PBPK) model was adapted to incorporate the new reduction model. This paper focuses on the toxicokinetics of Cr6 in the stomach compartment, where most of the extracellular Cr6 reduction is believed to occur in humans. Within the range of doses administered by the NTP bioassays, neither the original nor revised models predict saturation of stomach reducing capacity to occur in vivo if applying default parameters. However, both models still indicate that mice exhibit the lowest extent of reduction in the stomach, meaning that a higher percentage of the Cr6 dose may escape stomach reduction in that species. Similarly, both models predict that humans exhibit the highest extent of reduction at low doses. - Highlights: • We outline a new in vivo model for hexavalent chromium reduction in the stomach. • We examine in vivo reduction for mice, rats, and humans under varying conditions. • Species differences in toxicokinetics may explain susceptibility. • We show that a simplified stomach reduction model is adequate for extrapolation. • Internal dose uncertainties still exist.

Maltitol inhibits small intestinal glucose absorption and increases insulin mediated muscle glucose uptake ex vivo but not in normal and type 2 diabetic rats.

Science.gov (United States)

Chukwuma, Chika Ifeanyi; Ibrahim, Mohammed Auwal; Islam, Md Shahidul

2017-02-01

This study investigated the effects of maltitol on intestinal glucose absorption and muscle glucose uptake using ex vivo and in vivo experimental models. The ex vivo experiment was conducted in isolated jejunum and psoas muscle from normal rats. The in vivo study investigated the effects of a single bolus dose of maltitol on gastric emptying, intestinal glucose absorption and digesta transit in normal and type 2 diabetic rats. Maltitol inhibited glucose absorption in isolated rat jejunum and increased glucose uptake in isolated rat psoas muscle in the presence of insulin but not in the absence of insulin. In contrast, maltitol did not significantly (p > 0.05) alter small intestinal glucose absorption or blood glucose levels as well as gastric emptying and digesta transit in normal or type 2 diabetic rats. The results suggest that maltitol may not be a suitable dietary supplement for anti-diabetic food and food products to improve glycemic control.

In vivo imaging of brain androgen receptors in rats: a [18F]FDHT PET study

International Nuclear Information System (INIS)

Khayum, M.A.; Doorduin, J.; Antunes, I.F.; Kwizera, C.; Zijlma, R.; Boer, J.A. den; Dierckx, R.A.J.O.; Vries, E.F.J. de

2015-01-01

Introduction: Steroid hormones like androgens play an important role in the development and maintenance of several brain functions. Androgens can act through androgen receptors (AR) in the brain. This study aims to demonstrate the feasibility of positron emission tomography (PET) with 16β-[ 18 F]fluoro-5α-dihydrotestosterone ([ 18 F]FDHT) to image AR expression in the brain. Methods: Male Wistar rats were either orchiectomized to inhibit endogenous androgen production or underwent sham-surgery. Fifteen days after surgery, rats were subjected to a 90-min dynamic [ 18 F]FDHT PET scan with arterial blood sampling. In a subset of orchiectomized rats, 1 mg/kg dihydrotestosterone was co-injected with the tracer in order to saturate the AR. Plasma samples were analyzed for the presence of radioactive metabolites by radio-TLC. Pharmacokinetic modeling was performed to quantify brain kinetics of the tracer. After the PET scan, the animals were terminated for ex-vivo biodistribution. Results: PET imaging and ex vivo biodistribution studies showed low [ 18 F]FDHT uptake in all brain regions, except pituitary. [ 18 F]FDHT uptake in the surrounding cranial bones was high and increased over time. [ 18 F]FDHT was rapidly metabolized in rats. Metabolism was significantly faster in orchiectomized rats than in sham-orchiectomized rats. Quantitative analysis of PET data indicated substantial spill-over of activity from cranial bones into peripheral brain regions, which prevented further analysis of peripheral brain regions. Logan graphical analysis and kinetic modeling using 1- and 2-tissue compartment models showed reversible and homogenously distributed tracer uptake in central brain regions. [ 18 F]FDHT uptake in the brain could not be blocked by endogenous androgens or administration of dihydrotestosterone. Conclusion: The results of this study indicate that imaging of AR availability in rat brain with [ 18 F]FDHT PET is not feasible. The low AR expression in the brain, the

A comparative in vivo and in vitro L-band EPR study of irradiated rat incisors

International Nuclear Information System (INIS)

Zdravkova, M.; Gallez, B.; Debuyst, R.

2005-01-01

L-band (∼1GHz) EPR has the potential to measure the absorbed radiation dose in human teeth inside the mouth (in vivo analyses). One crucial point in the development of the method is to know if dosimetry evaluation carried out in vivo after accidental exposures can be reliably based on calibration curves built in vitro. The aim of the present work is to specifically address this point. First, we compared L-band in vitro and in vivo analyses in irradiated rat teeth and estimated the possible loss in in vivo experiments due to rat movements and mouth proximity. Second, the lower pair of rat incisors were analysed by L-band EPR before and after irradiation (50Gy), first on the living rat, then on the same dead rat, finally after extraction of the teeth. X-band powder spectra were also taken after crushing of the two teeth. Irradiations of dead rats and extracted teeth were also carried out. Comparing L-band spectra obtained with living rats and removed heads does not show any significant difference due to possible small rat movements or breathing. Relative standard deviations of the amplitudes of the dosimetric signal are quite high (27-54%). Nevertheless, it seems to be a tendency to have higher signals in irradiated extracted teeth than in irradiated animals

In vivo EPR pharmacokinetic evaluation of the redox status and the blood brain barrier permeability in the SOD1G93A ALS rat model.

Science.gov (United States)

Stamenković, Stefan; Pavićević, Aleksandra; Mojović, Miloš; Popović-Bijelić, Ana; Selaković, Vesna; Andjus, Pavle; Bačić, Goran

2017-07-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder affecting the motor pathways of the central nervous system. Although a number of pathophysiological mechanisms have been described in the disease, post mortem and animal model studies indicate blood-brain barrier (BBB) disruption and elevated production of reactive oxygen species as major contributors to disease pathology. In this study, the BBB permeability and the brain tissue redox status of the SOD1 G93A ALS rat model in the presymptomatic (preALS) and symptomatic (ALS) stages of the disease were investigated by in vivo EPR spectroscopy using three aminoxyl radicals with different cell membrane and BBB permeabilities, Tempol, 3-carbamoyl proxyl (3CP), and 3-carboxy proxyl (3CxP). Additionally, the redox status of the two brain regions previously implicated in disease pathology, brainstem and hippocampus, was investigated by spectrophotometric biochemical assays. The EPR results indicated that among the three spin probes, 3CP is the most suitable for reporting the intracellular redox status changes, as Tempol was reduced in vivo within minutes (t 1/2 =2.0±0.5min), thus preventing reliable kinetic modeling, whereas 3CxP reduction kinetics gave divergent conclusions, most probably due to its membrane impermeability. It was observed that the reduction kinetics of 3CP in vivo, in the head of preALS and ALS SOD1 G93A rats was altered compared to the controls. Pharmacokinetic modeling of 3CP reduction in vivo, revealed elevated tissue distribution and tissue reduction rate constants indicating an altered brain tissue redox status, and possibly BBB disruption in these animals. The preALS and ALS brain tissue homogenates also showed increased nitrilation, superoxide production, lipid peroxidation and manganese superoxide dismutase activity, and a decreased copper-zinc superoxide dismutase activity. The present study highlights in vivo EPR spectroscopy as a reliable tool for the investigation of

In Vivo Detection of the Effect of Electroacupuncture on “Zusanli” Acupoint in Rats with Adjuvant-Induced Arthritis through Optical Coherence Tomography

Science.gov (United States)

Yang, Hui; Zhou, Yan; Wu, Xiuli; Su, Chengkang; Long, Jia; Lin, Jin

2016-01-01

This study aimed to investigate the effect of electroacupuncture (EA) treatment through optical coherence tomography (OCT) in vivo on rats with adjuvant-induced arthritis. OCT images were obtained from the ankle of the right hind paws of the rats in control, model, and EA groups before modelling and 1 day, 8 days, 15 days, 22 days, and 29 days after modelling. Results demonstrated that the OCT signal of the ankle of the right hind paws of the rats was indistinct compared to 1 day after modelling and before modelling in the EA group. In the EA group, the light averaged attenuation coefficients of the ankle tissues decreased as treatment duration was prolonged after EA was administered (3.43, 2.96, 2.61, 2.42, and 2.29 mm−1, resp.). There was a significant difference in attenuation coefficient decrease between the 29th d and the 1st d for EA group compared with control group (P < 0.01). This condition indicated that the light absorption of the ankle of the treated rats in the EA group decreased. Therefore, OCT can be used to monitor the effect of treatment on rats with arthritis in vivo. PMID:27981046

In vivo measurement of hemodynamic information in stenosed rat blood vessels using X-ray PIV.

Science.gov (United States)

Park, Hanwook; Park, Jun Hong; Lee, Sang Joon

2016-11-28

Measurements of the hemodynamic information of blood flows, especially wall shear stress (WSS), in animal models with circulatory vascular diseases (CVDs) are important to understand the pathological mechanism of CVDs. In this study, X-ray particle image velocimetry (PIV) with high spatial resolution was applied to obtain velocity field information in stenosed blood vessels with high WSS. 3D clips fabricated with a 3D printer were applied to the abdominal aorta of a rat cadaver to induce artificial stenosis in the real blood vessel of an animal model. The velocity and WSS information of blood flows in the stenosed vessel were obtained and compared at various stenosis severities. In vivo measurement was also conducted by fastening a stenotic clip on a live rat model through surgical intervention to reduce the flow rate to match the limited temporal resolution of the present X-ray PIV system. Further improvement of the temporal resolution of the system might be able to provide in vivo measurements of hemodynamic information from animal disease models under physiological conditions. The present results would be helpful for understanding the relation between hemodynamic characteristics and the pathological mechanism in animal CVD models.

Radiography used to measure internal spinal cord deformation in an in vivo rat model.

Science.gov (United States)

Lucas, E; Whyte, T; Liu, J; Tetzlaff, W; Cripton, P A

2018-04-11

Little is known about the internal mechanics of the in vivo spinal cord during injury. The objective of this study was to develop a method of tracking internal and surface deformation of in vivo rat spinal cord during compression using radiography. Since neural tissue is radio-translucent, radio-opaque markers were injected into the spinal cord. Two tantalum beads (260 µm) were injected into the cord (dorsal and ventral) at C5 of nine anesthetized rats. Four beads were glued to the lateral surface of the cord, caudal and cranial to the injection site. A compression plate was displaced 0.5 mm, 2 mm, and 3 mm into the spinal cord and lateral X-ray images were taken before, during, and after each compression for measuring bead displacements. Potential bead migration was monitored for by comparing displacements of the internal and glued surface beads. Dorsal beads moved significantly more than ventral beads with a range in averages of 0.57-0.71 mm and 0.31-0.35 mm respectively. Bead displacements during 0.5 mm compressions were significantly lower than 2 mm and 3 mm compressions. There was no statistically significant migration of the internal beads. The results indicate the merit of this technique for measuring in vivo spinal cord deformation. The pattern of bead displacements illustrates the complex internal and surface deformations of the spinal cord during transverse compression. This information is needed for validating physical and finite element spinal cord surrogates and to define relationships between loading parameters, internal cord deformation, and biological and functional outcomes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Application of in vivo micro-computed tomography in the temporal characterisation of subchondral bone architecture in a rat model of low-dose monosodium iodoacetate-induced osteoarthritis

Science.gov (United States)

2011-01-01

Introduction Osteoarthritis (OA) is a complex, multifactorial joint disease affecting both the cartilage and the subchondral bone. Animal models of OA aid in the understanding of the pathogenesis of OA and testing suitable drugs for OA treatment. In this study we characterized the temporal changes in the tibial subchondral bone architecture in a rat model of low-dose monosodium iodoacetate (MIA)-induced OA using in vivo micro-computed tomography (CT). Methods Male Wistar rats received a single intra-articular injection of low-dose MIA (0.2 mg) in the right knee joint and sterile saline in the left knee joint. The animals were scanned in vivo by micro-CT at two, six, and ten weeks post-injection, analogous to early, intermediate, and advanced stages of OA, to assess architectural changes in the tibial subchondral bone. The articular cartilage changes in the tibiae were assessed macroscopically and histologically at ten weeks post-injection. Results Interestingly, tibiae of the MIA-injected knees showed significant bone loss at two weeks, followed by increased trabecular thickness and separation at six and ten weeks. The trabecular number was decreased at all time points compared to control tibiae. The tibial subchondral plate thickness of the MIA-injected knee was increased at two and six weeks and the plate porosity was increased at all time points compared to control. At ten weeks, histology revealed loss of proteoglycans, chondrocyte necrosis, chondrocyte clusters, cartilage fibrillation, and delamination in the MIA-injected tibiae, whereas the control tibiae showed no changes. Micro-CT images and histology showed the presence of subchondral bone sclerosis, cysts, and osteophytes. Conclusions These findings demonstrate that the low-dose MIA rat model closely mimics the pathological features of progressive human OA. The low-dose MIA rat model is therefore suitable to study the effect of therapeutic drugs on cartilage and bone in a non-trauma model of OA. In vivo

Step training in a rat model for complex aneurysmal vascular microsurgery

Directory of Open Access Journals (Sweden)

Martin Dan

2015-12-01

Full Text Available Introduction: Microsurgery training is a key step for the young neurosurgeons. Both in vascular and peripheral nerve pathology, microsurgical techniques are useful tools for the proper treatment. Many training models have been described, including ex vivo (chicken wings and in vivo (rat, rabbit ones. Complex microsurgery training include termino-terminal vessel anastomosis and nerve repair. The aim of this study was to describe a reproducible complex microsurgery training model in rats. Materials and methods: The experimental animals were Brown Norway male rats between 10-16 weeks (average 13 and weighing between 250-400g (average 320g. We performed n=10 rat hind limb replantations. The surgical steps and preoperative management are carefully described. We evaluated the vascular patency by clinical assessment-color, temperature, capillary refill. The rats were daily inspected for any signs of infections. The nerve regeneration was assessed by foot print method. Results: There were no case of vascular compromise or autophagia. All rats had long term survival (>90 days. The nerve regeneration was clinically completed at 6 months postoperative. The mean operative time was 183 minutes, and ischemia time was 25 minutes.

Cyclosporine A at reperfusion fails to reduce infarct size in the in vivo rat heart.

Science.gov (United States)

De Paulis, Damien; Chiari, Pascal; Teixeira, Geoffrey; Couture-Lepetit, Elisabeth; Abrial, Maryline; Argaud, Laurent; Gharib, Abdallah; Ovize, Michel

2013-09-01

We examined the effects on infarct size and mitochondrial function of ischemic (Isch), cyclosporine A (CsA) and isoflurane (Iso) preconditioning and postconditioning in the in vivo rat model. Anesthetized open-chest rats underwent 30 min of ischemia followed by either 120 min (protocol 1: infarct size assessment) or 15 min of reperfusion (protocol 2: assessment of mitochondrial function). All treatments administered before the 30-min ischemia (Pre-Isch, Pre-CsA, Pre-Iso) significantly reduced infarct as compared to control. In contrast, only Post-Iso significantly reduced infarct size, while Post-Isch and Post-CsA had no significant protective effect. As for the postconditioning-like interventions, the mitochondrial calcium retention capacity significantly increased only in the Post-Iso group (+58 % vs control) after succinate activation. Only Post-Iso increased state 3 (+177 and +62 %, for G/M and succinate, respectively) when compared to control. Also, Post-Iso reduced the hydrogen peroxide (H2O2) production (-46 % vs control) after complex I activation. This study suggests that isoflurane, but not cyclosporine A, can prevent lethal reperfusion injury in this in vivo rat model. This might be related to the need for a combined effect on cyclophilin D and complex I during the first minutes of reperfusion.

In vivo tracking of magnetically labeled mesenchmal stem cells injected via renal arteries in kidney failure rat

International Nuclear Information System (INIS)

Sun Junhui; Teng Gaojun; Ju Shenghong; Ma Zhanlong; Mai Xiaoli; Zhang Yu; Ma Ming

2006-01-01

Objective: To evaluate in vivo depiction and tracking for magnetically labeled bone marrow mesenchymal stern cells (MSCs) in a renal failure rat model injected intravascularly using a 1.5 T magnetic resonance imaging (MRI) system. Methods: Rat MSCs were isolated, purified, expanded and then incubated with home synthesized Fe 2 O 3 -PLL. Prussian blue stain was employed for identifying intracellular irons. An acute renal failure in rat was induced by intramuscular injection of glycerol and MSCs were injected into renal arteries of 11 recipients (labeled cells in six, unlabeled cells in five). MR images of kidneys were obtained respectively before injection of MSCs, and immediately, 1, 3, 5, and 8 clays after transplantation. MR imaging findings were analyzed, which were correlated with histological findings. Results: Rat MSCs were successfully labeled, and labeling efficiency was almost 100%. Prussian blue staining of Fe 2 O 3 -PLL labeled cells revealed the presence of iron-containing vesicles or endosomes in the cytoplasm. In the renal failure model of rats, the labeled MSCs were demonstrated as signal intensity loss in renal cortex on T 2 * -weighted MR images. The signal intensity decrease was visualized up to days 8 after transplantation. Histological analyses showed that most Prussian blue staining-positive cells were well correlated with the area where a signal intensity loss was observed in MRI. Signal intensity decrease was not detected after transplantation of unlabeled cells. Conclusion: The rat MSCs can be effectively labeled with Fe 2 O 3 -PLL. 1.5-T MR imaging seems to be a good technique to monitor the magnetically labeled MSCs in vivo in renal failure rat model intravascularly administered, which may have much more potential values for studying the engraftment of stem cells in kidneys. (authors)

Noninvasive Raman spectroscopy of rat tibiae: approach to in vivo assessment of bone quality

Science.gov (United States)

Okagbare, Paul I.; Begun, Dana; Tecklenburg, Mary; Awonusi, Ayorinde; Goldstein, Steven A.

2012-01-01

Abstract. We report on in vivo noninvasive Raman spectroscopy of rat tibiae using robust fiber-optic Raman probes and holders designed for transcutaneous Raman measurements in small animals. The configuration allows placement of multiple fibers around a rat leg, maintaining contact with the skin. Bone Raman data are presented for three regions of the rat tibia diaphysis with different thicknesses of overlying soft tissue. The ability to perform in vivo noninvasive Raman measurement and evaluation of subtle changes in bone composition is demonstrated with rat leg phantoms in which the tibia has carbonated hydroxylapatite, with different carbonate contents. Our data provide proof of the principle that small changes in bone composition can be monitored through soft tissue at anatomical sites of interest in biomedical studies. PMID:23085899

Intralipid minimizes hepatocytes injury after anoxia-reoxygenation in an ex vivo rat liver model.

Science.gov (United States)

Stadler, Michaela; Nuyens, Vincent; Boogaerts, Jean G

2007-01-01

Ischemia-reperfusion injury is a determinant in liver injury occurring during surgical procedures, ischemic states, and multiple organ failure. The pre-existing nutritional status of the liver, i.e., fasting, might contribute to the extent of tissue injury. This study investigated whether Intralipid, a solution containing soybean oil, egg phospholipids, and glycerol, could protect ex vivo perfused livers of fasting rats from anoxia-reoxygenation injury. The portal vein was cannulated, and the liver was removed and perfused in a closed ex vivo system. Isolated livers were perfused with glucose 5.5 and 15 mM, and two different concentrations of Intralipid, i.e., 0.5:100 and 1:100 (v/v) Intralipid 10%:medium (n = 5 in each group). The experiment consisted of perfusion for 15 min, warm anoxia for 60 min, and reoxygenation during 60 min. Hepatic enzymes, potassium, glucose, lactate, bilirubin, dienes, trienes, and cytochrome-c were analyzed in perfusate samples. The proportion of glycogen in hepatocytes was determined in biopsies. Intralipid attenuated transaminases, lactate dehydrogenase, potassium, diene, and triene release in the perfusate (dose-dependant) during the reoxygenation phase when compared with glucose-treated groups. The concentration of cytochrome-c in the medium was the highest in the 5.5-mM glucose group. The glycogen content was low in all livers at the start of the experiment. Intralipid presents, under the present experimental conditions, a better protective effect than glucose in anoxia-reoxygenation injury of the rat liver.

In vivo postprandial lipid partitioning in liver and muscle of diabetic rats is disturbed

NARCIS (Netherlands)

Prompers, J.J.; Jonkers, R.A.M.; Loon, van L.J.C.; Nicolay, K.

2012-01-01

Objective: To study in vivo lipid partitioning in insulin-resistant liver and muscle of diabetic rats using magnetic resonance spectroscopy (MRS). Methods: Four groups of n=6 male Zucker diabetic fatty rats were used for this study: obese, pre-diabetic fa/fa rats and lean, non-diabetic fa/+

In vivo and in vitro dermal penetration of 2,4,5,2',4', 5'-hexachlorobiphenyl in young and adult rats

International Nuclear Information System (INIS)

Shah, P.V.; Sumler, M.R.; Fisher, H.L.; Hall, L.L.

1989-01-01

Penetration of 2,4,5,2',4',5'-[ 14 C]hexachlorobiphenyl (HCB) through skin of young (33 days) and adult (82 days) female Fischer 344 rats was determined in vivo and by two in vitro methods. In vivo dermal penetration at 120 hr was 45% in young and 43% in adults. At 72 hr in vivo dermal penetration was 35% in young and 26% in adults compared to 1.5% for young and 1.0% for adult as measured with a continuous flow in vitro system and 2.9% for young and 1.9% for adults as measured with a static in vitro system. Most of the dermally absorbed HCB remained in the body as only 4.9 and 2.6% of that absorbed was excreted by young and adult rats, respectively, at the end of 120 hr. Significant differences in dermal penetration and kinetics of HCB between young and adult female rats were observed. The elimination of ECB-derived material was approximately six times higher in feces than in urine. A physiological pharmacokinetic model was fitted to the organ and tissue radioactivity distribution data. Parameters in the model determined from dermal dosing of female Fischer 344 rats were in reasonable agreement with those reported in the literature for adult male Sprague-Dawley rats (iv dose). The rate constant for dermal penetration was 0.83 x 10 -4 min -1 for adults and 0.96 x 10 -4 min -1 for young. The delay or lag time parameter for dermal penetration was 4.4 hr in adults and 1.1 hr in young

Ultrasound thermography: A new temperature reconstruction model and in vivo results

Science.gov (United States)

Bayat, Mahdi; Ballard, John R.; Ebbini, Emad S.

2017-03-01

The recursive echo strain filter (RESF) model is presented as a new echo shift-based ultrasound temperature estimation model. The model is shown to have an infinite impulse response (IIR) filter realization of a differentitor-integrator operator. This model is then used for tracking sub-therapeutic temperature changes due to high intensity focused ultrasound (HIFU) shots in the hind limb of the Copenhagen rats in vivo. In addition to the reconstruction filter, a motion compensation method is presented which takes advantage of the deformation field outside the region of interest to correct the motion errors during temperature tracking. The combination of the RESF model and motion compensation algorithm is shown to greatly enhance the accuracy of the in vivo temperature estimation using ultrasound echo shifts.

In Vivo Imaging of Glial Activation after Unilateral Labyrinthectomy in the Rat: A [18F]GE180-PET Study

Directory of Open Access Journals (Sweden)

Andreas Zwergal

2017-12-01

Full Text Available The functional relevance of reactive gliosis for recovery from acute unilateral vestibulopathy is unknown. In the present study, glial activation was visualized in vivo by [18F]GE180-PET in a rat model of unilateral labyrinthectomy (UL and compared to behavioral vestibular compensation (VC overtime. 14 Sprague-Dawley rats underwent a UL by transtympanic injection of bupivacaine/arsenilate, 14 rats a SHAM UL (injection of normal saline. Glial activation was depicted with [18F]GE180-PET and ex vivo autoradiography at baseline and 7, 15, 30 days after UL/SHAM UL. Postural asymmetry and nystagmus were registered at 1, 2, 3, 7, 15, 30 days after UL/SHAM UL. Signs of vestibular imbalance were found only after UL, which significantly decreased until days 15 and 30. In parallel, [18F]GE180-PET and ex vivo autoradiography depicted glial activation in the ipsilesional vestibular nerve and nucleus on days 7 and 15 after UL. Correlation analysis revealed a strong negative association of [18F]GE180 uptake in the ipsilesional vestibular nucleus on day 7 with the rate of postural recovery (R = −0.90, p < 0.001, suggesting that glial activation accelerates VC. In conclusion, glial activation takes place in the ipsilesional vestibular nerve and nucleus within the first 30 days after UL in the rat and can be visualized in vivo by [18F]GE180-PET.

X-ray PIV measurement of blood flow in deep vessels of a rat: An in vivo feasibility study.

Science.gov (United States)

Park, Hanwook; Yeom, Eunseop; Lee, Sang Joon

2016-01-18

X-ray PIV measurement is a noninvasive approach to measure opaque blood flows. However, it is not easy to measure real pulsatile blood flows in the blood vessels located at deep position of the body, because the surrounding tissues significantly attenuate the contrast of X-ray images. This study investigated the effect of surrounding tissues on X-ray beam attenuation by measuring the velocity fields of blood flows in deep vessels of a live rat. The decrease in image contrast was minimized by employing biocompatible CO2 microbubbles as tracer particles. The maximum measurable velocity of blood flows in the abdominal aorta of a rat model was found through comparative examination between the PIV measurement accuracy and the level of image contrast according to the input flow rate. Furthermore, the feasibility of using X-ray PIV to accurately measure in vivo blood flows was demonstrated by determining the velocity field of blood flows in the inferior vena cava of a rat. This study may serve as a reference in conducting in vivo X-ray PIV measurements of pulsatile blood flows in animal disease models and investigating hemodynamic characteristics and circulatory vascular diseases.

In vivo electrophysiological measurement of the rat ulnar nerve with axonal excitability testing

DEFF Research Database (Denmark)

Wild, Brandon M.; Morris, Renée; Moldovan, Mihai

2018-01-01

Electrophysiology enables the objective assessment of peripheral nerve function in vivo. Traditional nerve conduction measures such as amplitude and latency detect chronic axon loss and demyelination, respectively. Axonal excitability techniques "by threshold tracking" expand upon these measures...... by providing information regarding the activity of ion channels, pumps and exchangers that relate to acute function and may precede degenerative events. As such, the use of axonal excitability in animal models of neurological disorders may provide a useful in vivo measure to assess novel therapeutic...... interventions. Here we describe an experimental setup for multiple measures of motor axonal excitability techniques in the rat ulnar nerve. The animals are anesthetized with isoflurane and carefully monitored to ensure constant and adequate depth of anesthesia. Body temperature, respiration rate, heart rate...

In vivo dermal absorption of pyrethroid pesticides in the rat.

Science.gov (United States)

The potential for exposure to pyrethroid pesticides has risen recently because of their increased use. The objective of this study was to examine the in vivo dermal absorption of bifenthrin, deltamethrin and permethrin in the rat. Hair on the dorsal side of anesthetized adult m...

Immune-mediated effects upon oral challenge of ovalbumin-sensitized Brown Norway rats: Further characterization of a rat food allergy model

NARCIS (Netherlands)

Knippels, L.M.J.; Penninks, A.H.; Smit, J.J.; Houben, G.F.

1999-01-01

Although several in vivo antigenicity assays using parenteral immunization are operational, no full validated enteral models are available to study food allergy and allergenicity of food proteins. To further validate a developed enteral Brown Norway (BN) rat food allergy model, systemic and local

Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells—Characterization of a New in Vivo Model

Directory of Open Access Journals (Sweden)

Sonja Stojković

2016-06-01

Full Text Available Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl-1-nitrosourea (BCNU and temozolomide (TMZ. Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells’ invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats’ behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells.

Comparison of Allogeneic and Syngeneic Rat Glioma Models by Using MRI and Histopathologic Evaluation.

Science.gov (United States)

Biasibetti, Elena; Valazza, Alberto; Capucchio, Maria T; Annovazzi, Laura; Battaglia, Luigi; Chirio, Daniela; Gallarate, Marina; Mellai, Marta; Muntoni, Elisabetta; Peira, Elena; Riganti, Chiara; Schiffer, Davide; Panciani, Pierpaolo; Lanotte, Michele

2017-03-01

Research in neurooncology traditionally requires appropriate in vivo animal models, on which therapeutic strategies are tested before human trials are designed and proceed. Several reproducible animal experimental models, in which human physiologic conditions can be mimicked, are available for studying glioblastoma multiforme. In an ideal rat model, the tumor is of glial origin, grows in predictable and reproducible patterns, closely resembles human gliomas histopathologically, and is weakly or nonimmunogenic. In the current study, we used MRI and histopathologic evaluation to compare the most widely used allogeneic rat glioma model, C6-Wistar, with the F98-Fischer syngeneic rat glioma model in terms of percentage tumor growth or regression and growth rate. In vivo MRI demonstrated considerable variation in tumor volume and frequency between the 2 rat models despite the same stereotactic implantation technique. Faster and more reproducible glioma growth occurred in the immunoresponsive environment of the F98-Fischer model, because the immune response is minimized toward syngeneic cells. The marked inability of the C6-Wistar allogeneic system to generate a reproducible model and the episodes of spontaneous tumor regression with this system may have been due to the increased humoral and cellular immune responses after tumor implantation.

Diltiazem Reduces Mortality and Breakdown of ATP in Red Blood Cell Induced by Isoproterenol in a Freely Moving Rat Model in Vivo

Directory of Open Access Journals (Sweden)

Pollen K.F. Yeung

2014-09-01

Full Text Available The benefit of calcium channel blockers for cardiovascular prevention against heart attack and stroke has not been firmly supported. We investigated the possible cardiovascular protective effect of diltiazem (DTZ against injury induced by isoproterenol using a freely moving rat model in vivo. Sprague Dawley rats were injected subcutaneously (sc with either 5 or 10 mg/kg of DTZ, or saline as control, twice daily for five doses. One hour after the last injection, a single dose of isoproterenol (30 mg/kg was injected sc to each rat. Blood samples were collected serially for 6 h for measurement of adenine nucleotides (ATP, ADP and AMP in red blood cell (RBC by a validated HPLC. The study has shown isoproterenol induced 50% mortality and also increased RBC concentrations of AMP from 0.04 ± 0.02 to 0.29 ± 0.21 mM at the end of the experiment (p < 0.05. Treatment with 10 mg/kg of DTZ reduced mortality from 50% to <20% and attenuated the increase of RBC concentrations of AMP from +0.25 ± 0.22 in the control rats to +0.072 ± 0.092 mM (p < 0.05. The study concluded that 10 mg/kg of DTZ reduced mortality and breakdown of ATP induced by isoproterenol in rats.

Stimulus-dependent changes of extracellular glucose in the rat hippocampus determined by in vivo microdialysis.

Science.gov (United States)

Rex, A; Bert, B; Fink, H; Voigt, J-P

2009-10-19

Neuronal activity is tightly coupled with brain energy metabolism; and glucose is an important energy substrate for neurons. The present in vivo microdialysis study was aimed at investigating changes in extracellular glucose concentrations in the rat ventral hippocampus due to exposure to the elevated plus maze. Determination of basal hippocampal glucose and lactate/pyruvate ratio in male Wistar rats was conducted in the home cage using in vivo microdialysis. Rats were exposed to the elevated plus maze, a rodent model of anxiety-related behaviour, or to unspecific stress induced by white noise (95dB) as a control condition. Basal hippocampal levels of glucose, as determined by zero-net-flux, and the basal lactate/pyruvate ratio were 1.49+/-0.05mmol/l and 13.8+/-1.1, respectively. In rats without manipulation, glucose levels remained constant throughout the experiment (120min). By contrast, exposure to the elevated plus maze led to a temporary decline in hippocampal glucose (-33.2+/-4.4%) which returned to baseline level in the home cage. White noise caused only a non-significant decrease in extracellular glucose level (-9.3+/-3.5%). In all groups, the lactate/pyruvate ratio remained unchanged by the experimental procedures. Our microdialysis study demonstrates that exposure to the elevated plus maze induces a transient decrease in extracellular hippocampal glucose concentration. In contrast, an unspecific stimulus did not change hippocampal glucose. The latter suggests that only specific behavioural stimuli increase hippocampal glucose utilization in the ventral hippocampus.

In vivo study about specific captation of 125 I-insulin by rat brain structures

International Nuclear Information System (INIS)

Sanvitto, G.L.

1986-01-01

The specific captation of 125 I-insulin was evaluated by brain structures, as olfactory bulbous, hypothalamus and cerebellum in rats, from in vivo experiences that including two different aspects: captation measure of 125 I-insulin after the intravenous injection of the labelled hormone, in fed rats and in rats with 48 h of fast or convulsion, procedure by the pentylene tetrazole; captation measure of 125 I-insulin after intra-cerebral-ventricular injection of the labelled hormone in fed rats. (C.G.C.)

The effect of cyclic compression on the mechanical properties of the inter-vertebral disc: an in vivo study in a rat tail model.

Science.gov (United States)

Ching, Congo T S; Chow, Daniel H K; Yao, Fiona Y D; Holmes, Andrew D

2003-03-01

To assess the changes in the mechanical properties of inter-vertebral discs in vivo following static and cyclic compressive loading of different frequencies. An in vivo biomechanical study using a rat-tail model of the inter-vertebral disc.Background. Mechanical loading has been suggested as playing a major role in the etiology of disc degeneration, but the relationship is still not fully understood. Sixty Sprague-Dawley rats were subject to daily compressive stress via pins inserted in the 6th and 7th caudal vertebrae over a two-week loading period. Animals were randomly divided into a sham group (pin insertion, no loading), a static loading group, or cyclic loading groups of 0.5, 1.5, or 2.5 Hz. Loading was applied for 1 h each day from the 3rd to 17th day following pin insertion, and the angular compliance, angular laxity, and inter-pin distance were measured in vivo at days 0, 3, 10 and 17. Changes in the inter-vertebral disc height depended on the frequency of loading, with the decrease in disc height in the static compression group significantly greater than that in all other groups, whereas the decrease in the 1.5 Hz cyclic compression group was significantly smaller than that in all other compression groups. Changes in disc properties depend on both the total load exposure and the frequency of loading. Cyclic loading in general produced less marked changes than static loading, but loading at particular frequencies may result in more severe changes. Previous studies have shown the in vivo changes in the mechanical properties of inter-vertebral discs to depend on the magnitude and duration of loading. In this study, a frequency dependent response to cyclic loading is also demonstrated.

Evaluation of anticonvulsant actions of dibromophenyl enaminones using in vitro and in vivo seizure models.

Directory of Open Access Journals (Sweden)

Mohamed G Qaddoumi

Full Text Available Epilepsy and other seizure disorders are not adequately managed with currently available drugs. We recently synthesized a series of dibromophenyl enaminones and demonstrated that AK6 and E249 were equipotent to previous analogs but more efficacious in suppressing neuronal excitation. Here we examined the actions of these lead compounds on in vitro and in vivo seizure models. In vitro seizures were induced in the hippocampal slice chemically (zero Mg2+ buffer and picrotoxin and electrically using patterned high frequency stimulation (HFS of afferents. In vivo seizures were induced in rats using the 6 Hz and the maximal electroshock models. AK6 (10 µM and E249 (10 µM depressed the amplitude of population spikes recorded in area CA1 of the hippocampus by -50.5±4.3% and -40.1±3.1% respectively, with partial recovery after washout. In the zero Mg2+ model, AK6 (10 µM depressed multiple population spiking (mPS by -59.3±6.9% and spontaneous bursts (SBs by -65.9±7.2% and in the picrotoxin-model by -43.3±7.2% and -50.0±8.3%, respectively. Likewise, E249 (10 µM depressed the zero-Mg2+-induced mPS by -48.8±9.5% and SBs by -55.8±15.5%, and in the picrotoxin model by -37.1±5.5% and -56.5±11.4%, respectively. They both suppressed post-HFS induced afterdischarges and SBs. AK6 and E249 dose-dependently protected rats in maximal electroshock and 6 Hz models of in vivo seizures after 30 min pretreatment. Their level of protection in both models was similar to that obtained with phenytoin Finally, while AK6 had no effect on locomotion in rats, phenytoin significantly decreased locomotion. AK6 and E249, suppressed in vitro and in vivo seizures to a similar extent. Their in vivo activities are comparable with but not superior to phenytoin. The most efficacious, AK6 produced no locomotor suppression while phenytoin did. Thus, AK6 and E249 may be excellent candidates for further investigation as potential agents for the treatment of epilepsy syndromes

Ultrasound method applied to characterize healthy femoral diaphysis of Wistar rats in vivo

International Nuclear Information System (INIS)

Fontes-Pereira, A.; Matusin, D.P.; Rosa, P.; Schanaider, A.; Krüger, M.A. von; Pereira, W.C.A.

2014-01-01

A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses of Wistar rats in vivo. Five quantitative parameters [apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), time slope of apparent backscatter (TSAB), integrated reflection coefficient (IRC), and frequency slope of integrated reflection (FSIR)] were calculated using the echoes from cortical and trabecular bone in the femurs of 14 Wistar rats. Signal acquisition was performed three times in each rat, with the ultrasound signal acquired along the femur's central region from three positions 1 mm apart from each other. The parameters estimated for the three positions were averaged to represent the femur diaphysis. The results showed that AIB, FSAB, TSAB, and IRC values were statistically similar, but the FSIR values from Experiments 1 and 3 were different. Furthermore, Pearson's correlation coefficient showed, in general, strong correlations among the parameters. The proposed protocol and calculated parameters demonstrated the potential to characterize the femur diaphysis of rats in vivo. The results are relevant because rats have a bone structure very similar to humans, and thus are an important step toward preclinical trials and subsequent application of QUS in humans

Accumulation of the anandamide precursor and other N-acylethanolamine phospholipids in infant rat models of in vivo necrotic and apoptotic neuronal death

DEFF Research Database (Denmark)

Hansen, H.H.; Ikonomidou, C.; Bittigau, P.

2001-01-01

infant rat models of in vivo neurodegeneration: (i) necrosis caused by intrastriatal injection of NMDA (25 nmol); (ii) apoptosis induced by systemic administration of the NMDA-receptor antagonist (+)MK-801 (3 × 0.5 mg/kg, i.p.); and (iii) apoptosis following focal necrosis triggered by concussive head......-801 did not alter cortical NAPE levels. Concussion head trauma resulted in a similar but less pronounced upregulation of NAPE levels at both 4 and 24 h as compared to NMDA injections. Increased levels of NAPE 24 h post-trauma possibly reflect that necrosis is still ongoing at this time point...

In vivo Dentin Caries Model using Rat Molars

OpenAIRE

Takashi, HIGASHI; Junji, TAGAMI; Nobuhiro, HANADA; Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University; Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo Medical and Dental University; Department of Oral Science The National Institute of Infectious Diseases(NIID)

2000-01-01

Experimental dentinal caries was induced in rat molars which were inoculated orally with Streptococcus mutans and maintained on a carionenic diet 2000. After 30 days on the diet, the rats were sacrificed. The caries lesions were confirmed with a caries detector, then nanohardness determination of caries dentin were measured with nanoindentation. After hardness measurement, the lesion was examined by SEM and EDS. Dentin caries in sixteen fissures was induced among 20 fissures in the mandibular...

Experimental In Vivo Models of Candidiasis

Directory of Open Access Journals (Sweden)

Esther Segal

2018-02-01

Full Text Available Candidiasis is a multifaceted fungal disease including mucosal-cutaneous, visceral, and disseminated infections caused by yeast species of the genus Candida. Candida infections are among the most common human mycoses. Candida species are the third to fourth most common isolates from bloodstream infections in neutropenic or immunocompromised hospitalized patients. The mucosal-cutaneous forms—particularly vaginal infections—have a high prevalence. Vaginitis caused by Candida species is the second most common vaginal infection. Hence, candidiasis is a major subject for research, including experimental in vivo models to study pathogenesis, prevention, or therapy of the disease. The following review article will focus on various experimental in vivo models in different laboratory animals, such as mammals (mice, rats, rabbits, the fruit fly–Drosophila melanogaster, the larvae of the moth Galleria mellonella, or the free-living nematode Caenorhabditis elegans. The review will describe the induction of the different clinical forms of candidiasis in the various models and the validity of such models in mimicking the human clinical situations. The use of such models for the assessment of antifungal drugs, evaluation of potential vaccines to protect before candidiasis, exploration of Candida virulence factors, and comparison of pathogenicity of different Candida species will be included in the review. All of the above will be reported as based on published studies of numerous investigators as well as on the research of the author and his group.

Consequences of Mrp2 deficiency for diclofenac toxicity in the rat intestine ex vivo

NARCIS (Netherlands)

Niu, Xiaoyu; de Graaf, Inge A. M.; van de Vegte, Dennis; Langelaar-Makkinje, Miriam; Sekine, Shuichi; Groothuis, Geny M. M.

The non-steroidal anti-inflammatory drug diclofenac (DCF) has a high prevalence of intestinal side effects in humans and rats. It has been reported that Mrp2 transporter deficient rats (Mrp2) are more resistant to DCF induced intestinal toxicity. This was explained in vivo by impaired Mrp2-dependent

In vivo bioluminescence imaging for prolonged survival of transplanted human neural stem cells using 3D biocompatible scaffold in corticectomized rat model.

Directory of Open Access Journals (Sweden)

Do Won Hwang

Full Text Available Stem cell-based treatment of traumatic brain injury has been limited in its capacity to bring about complete functional recovery, because of the poor survival rate of the implanted stem cells. It is known that biocompatible biomaterials play a critical role in enhancing survival and proliferation of transplanted stem cells via provision of mechanical support. In this study, we noninvasively monitored in vivo behavior of implanted neural stem cells embedded within poly-l-lactic acid (PLLA scaffold, and showed that they survived over prolonged periods in corticectomized rat model. Corticectomized rat models were established by motor-cortex ablation of the rat. F3 cells expressing enhanced firefly luciferase (F3-effLuc were established through retroviral infection. The F3-effLuc within PLLA was monitored using IVIS-100 imaging system 7 days after corticectomized surgery. F3-effLuc within PLLA robustly adhered, and gradually increased luciferase signals of F3-effLuc within PLLA were detected in a day dependent manner. The implantation of F3-effLuc cells/PLLA complex into corticectomized rats showed longer-lasting luciferase activity than F3-effLuc cells alone. The bioluminescence signals from the PLLA-encapsulated cells were maintained for 14 days, compared with 8 days for the non-encapsulated cells. Immunostaining results revealed expression of the early neuronal marker, Tuj-1, in PLLA-F3-effLuc cells in the motor-cortex-ablated area. We observed noninvasively that the mechanical support by PLLA scaffold increased the survival of implanted neural stem cells in the corticectomized rat. The image-guided approach easily proved that scaffolds could provide supportive effect to implanted cells, increasing their viability in terms of enhancing therapeutic efficacy of stem-cell therapy.

Inhibition of galactosamine cytotoxicity in an in vivo/in vitro hepatocellular toxicity model

International Nuclear Information System (INIS)

MacDonald, J.R.; Thayer, K.J.; White, C.

1987-01-01

A combined in vivo/in vitro model of galactosamine hepatotoxicity was employed to test whether previously reported cytoprotective actions of cystamine administration on galactosamine-induced hepatic injury in vivo could be attributed to a direct action of cystamine on toxicant-challenged hepatocytes. In this model, male Sprague-Dawley rats received a 400 mg/kg galactosamine challenge via intraperitoneal injection 1 hr prior to portal vein cannulation for hepatocyte isolation. Isolated cells are established in monolayer culture and galactosamine-induced cellular injury is then expressed over the ensuing 24-48 hr in culture. Consistent with the biochemical basis of galactosamine-induced hepatocellular injury in vivo, cytotoxicity could be prevented by in vitro uridine treatments within 3 hr of the in vivo galactosamine challenge, but not when added 12 hr later. Cystamine, in contrast, exhibited a cytoprotective effect even when added to cultures 12 hr after the in vivo toxicant challenge. Post-toxicant cytoprotection by cystamine in vitro was concentration dependent and did not produce an alteration of hepatocyte nonprotein sulfhydryl content. Post-toxicant cytoprotection by uridine and cystamine in this in vivo/in vitro model of toxicity were fully consistent with in vivo protection from galactosamine-induced necrosis by these agents. This model eliminates potential extrahepatic mechanisms for cystamine's hepatoprotective effect and demonstrates a direct cytoprotective action on galactosamine-challenged hepatocytes

Effect of aging on phosphate metabolites of rat brain as revealed by the in vivo and in vitro 31P NMR measurements

International Nuclear Information System (INIS)

Liu, Hsiuchih; Chi, Chinwen; Liu, Tsungyun; Liu, Lianghui; Luh, Wenming; Hsieh, Changhuain; Wu, Wenguey

1991-01-01

Changes of phosphate metabolism in brains of neonate, weaning and adult rats were compared using both in vivo and in vitro nuclear magnetic resonance spectra. Ratios of phosphocreatine/nucleoside triphosphate (PCr/NTP) were the same in neonatal brain in both in vivo and in vitro studies, but not in weaning and adult brains. This discrepancy may have resulted from extended cerebral hypoxia due to slowed freezing of the brain by the increased skull thickness and brain mass in the weaning and adult rats. Variations of in vitro extraction condition for this age-related study may lead to systematic errors in the adult rats. Nevertheless, the phosphomonoester/nucleoside triphosphate (PME/NTP) ratios in extracts of brain from neonatal rats were higher than those obtained in vivo. In addition, the glycerophosphorylethanolamine plus glycerophosphorylcholine/nucleoside triphosphate (GPE+GPC/NTP) ratios, which were not measurable in vivo, showed age-dependent increase in extracts of rat brain. Some of the phosphomonoester and phosphodiester molecules in rat brain may be undetectable in in vivo NMR analysis because of their interaction with cellular components. The total in vitro GPE and GPC concentration in brain from neonatal rat was estimated to be 0.34 mmole/g wet tissue

In vivo somatostatin, vasopressin, and oxytocin synthesis in diabetic rat hypothalamus

International Nuclear Information System (INIS)

Fernstrom, J.D.; Fernstrom, M.H.; Kwok, R.P.

1990-01-01

The in vivo labeling of somatostatin-14, somatostatin-28, arginine vasopressin, and oxytocin was studied in rat hypothalamus after third ventricular administration of [35S]cysteine to streptozotocin-diabetic and normal rats. Immunoreactive somatostatin levels in hypothalamus were unaffected by diabetes, as was the incorporation of [35S]cysteine into hypothalamic somatostatin-14 and somatostatin-28. In contrast, immunoreactive vasopressin levels in hypothalamus and posterior pituitary (and oxytocin levels in posterior pituitary) were below normal in diabetic rats. Moreover, [35S]cysteine incorporation into hypothalamic vasopressin and oxytocin (probably mainly in the paraventricular nucleus because of its proximity to the third ventricular site of label injection) was significantly above normal. The increments in vasopressin and oxytocin labeling were reversed by insulin administration. In vivo cysteine specific activity and the labeling of acid-precipitable protein did not differ between normal and diabetic animals; effects of diabetes on vasopressin and oxytocin labeling were therefore not caused by simple differences in cysteine specific activity. These results suggest that diabetes (1) does not influence the production of somatostatin peptides in hypothalamus but (2) stimulates the synthesis of vasopressin and oxytocin. For vasopressin at least, the increase in synthesis may be a compensatory response to the known increase in its secretion that occurs in uncontrolled diabetes

Effect of two novel CGRP-binding compounds in a closed cranial window rat model

DEFF Research Database (Denmark)

Juhl, Louise Kathrine; Edvinsson, Lars; Olesen, Jes

2007-01-01

We investigated the in vivo effects of two novel calcitonin gene-related peptide (CGRP) binding molecules in the genuine closed cranial window model in the rat. The RNA-Spiegelmer (NOX-C89) and the monoclonal CGRP antibody are CGRP scavengers and might be used as an alternative to CGRP-receptor a......We investigated the in vivo effects of two novel calcitonin gene-related peptide (CGRP) binding molecules in the genuine closed cranial window model in the rat. The RNA-Spiegelmer (NOX-C89) and the monoclonal CGRP antibody are CGRP scavengers and might be used as an alternative to CGRP......-receptor antagonists in the treatment of migraine. Rats were anaesthetized and a closed cranial window established. Changes in dural and pial artery diameter and mean arterial blood pressure were measured simultaneously. Infusion of the RNA-Spiegelmer or the CGRP antibody alone had no effect on the arteries...... and the consequent liberation of CGRP from perivascular sensory nerve fibres....

Simultaneous in vivo visualization and localization of solid oral dosage forms in the rat gastrointestinal tract by magnetic resonance imaging (MRI).

Science.gov (United States)

Christmann, V; Rosenberg, J; Seega, J; Lehr, C M

1997-08-01

Bioavailability of orally administered drugs is much influenced by the behavior, performance and fate of the dosage form within the gastrointestinal (GI) tract. Therefore, MRI in vivo methods that allow for the simultaneous visualization of solid oral dosage forms and anatomical structures of the GI tract have been investigated. Oral contrast agents containing Gd-DTPA were used to depict the lumen of the digestive organs. Solid oral dosage forms were visualized in a rat model by a 1H-MRI double contrast technique (magnetite-labelled microtablets) and a combination of 1H- and 19F-MRI (fluorine-labelled minicapsules). Simultaneous visualization of solid oral dosage forms and the GI environment in the rat was possible using MRI. Microtablets could reproducibly be monitored in the rat stomach and in the intestines using a 1H-MRI double contrast technique. Fluorine-labelled minicapsules were detectable in the rat stomach by a combination of 1H- and 19F-MRI in vivo. The in vivo 1H-MRI double contrast technique described allows solid oral dosage forms in the rat GI tract to be depicted. Solid dosage forms can easily be labelled by incorporating trace amounts of non-toxic iron oxide (magnetite) particles. 1H-MRI is a promising tool for observing such pharmaceutical dosage forms in humans. Combined 1H- and 19F-MRI offer a means of unambiguously localizing solid oral dosage forms in more distal parts of the GI tract. Studies correlating MRI examinations with drug plasma levels could provide valuable information for the development of pharmaceutical dosage forms.

The role of aryl hydrocarbon receptor signaling pathway in cardiotoxicity of acute lead intoxication in vivo and in vitro rat model.

Science.gov (United States)

Ansari, Mushtaq A; Maayah, Zaid H; Bakheet, Saleh A; El-Kadi, Ayman O; Korashy, Hesham M

2013-04-05

Lead (Pb(2+)) is a naturally occurring systemic toxicant heavy metal that affects several organs in the body including the kidneys, liver, and central nervous system. However, Pb(2+)-induced cardiotoxicity has never been investigated yet and the exact mechanism of Pb(2+) associated cardiotoxicity has not been studied. The current study was designed to investigate the potential effect of Pb(2+) to induce cardiotoxicity in vivo and in vitro rat model and to explore the molecular mechanisms and the role of aryl hydrocarbon receptor (AhR) and regulated gene, cytochrome P4501A1 (CYP1A1), in Pb(2+)-mediated cardiotoxicity. For these purposes, Wistar albino rats were treated with Pb(2+) (25, 50 and 100mg/kg, i.p.) for three days and the effects on physiological and histopathological parameters of cardiotoxicity were determined. At the in vitro level, rat cardiomyocyte H9c2 cell lines were incubated with increasing concentration of Pb(2+) (25, 50, and 100 μM) and the expression of hypertrophic genes, α- and β-myosin heavy chain (α-MHC and β-MHC), brain Natriuretic Peptide (BNP), and CYP1A1 were determined at the mRNA and protein levels using real-time PCR and Western blot analysis, respectively. The results showed that Pb(2+) significantly induced cardiotoxicity and heart failure as evidenced by increase cardiac enzymes, lactate dehydrogenase and creatine kinase and changes in histopathology in vivo. In addition, Pb(2+) treatment induced β-MHC and BNP whereas inhibited α-MHC mRNA and protein levels in vivo in a dose-dependent manner. In contrast, at the in vitro level, Pb(2+) treatment induced both β-MHC and α-MHC mRNA levels in time- and dose-dependent manner. Importantly, these changes were accompanied with a proportional increase in the expression of CYP1A1 mRNA and protein expression levels, suggesting a role for the CYP1A1 in cardiotoxicity. The direct evidence for the involvement of CYP1A1 in the induction of cardiotoxicity by Pb(2+) was evidenced by the

In vivo studies on the nitrogen, chlorine, calcium and phosphorus composition of rats by neutron activation analysis

International Nuclear Information System (INIS)

Morel-Jacrot, Micheline.

1975-01-01

The role of neutron activation analysis 'in vivo' to determine the elementary composition of the rat organism is demonstrated. In part one the possibilities offered by certain methods which establish the elementary composition of living organisms are analyzed, together with the contribution and scope of neutron activation analysis. In part two the technical details of the neutron activation of rats in vivo are determined and the problems raised by application of the method considered. This is followed by an application of neutron activation analysis to research on changes in the nitrogen, chlorine, calcium and phosphorus composition of rats during growth (from 30 to 440 days) and important biological events such as puberty in both sexes, reproduction and lactation. Finally a study of the fertility rate and the effects of repeated irradiations on Sprague-Dawley rats are described [fr

In vivo microwave-based thermoacoustic tomography of rats (Conference Presentation)

Science.gov (United States)

Lin, Li; Zhou, Yong; Wang, Lihong V.

2016-03-01

Microwave-based thermoacoustic tomography (TAT), based on the measurement of ultrasonic waves induced by microwave pulses, can reveal tissue dielectric properties that may be closely related to the physiological and pathological status of the tissues. Using microwaves as the excitation source improved imaging depth because of their deep penetration into biological tissues. We demonstrate, for the first time, in vivo microwave-based thermoacoustic imaging in rats. The transducer is rotated around the rat in a full circle, providing a full two-dimensional view. Instead of a flat ultrasonic transducer, we used a virtual line detector based on a cylindrically focused transducer. A 3 GHz microwave source with 0.6 µs pulse width and an electromagnetically shielded transducer with 2.25 MHz central frequency provided clear cross-sectional images of the rat's body. The high imaging contrast, based on the tissue's rate of absorption, and the ultrasonically defined spatial resolution combine to reveal the spine, kidney, muscle, and other deeply seated anatomical features in the rat's abdominal cavity. This non-invasive and non-ionizing imaging modality achieved an imaging depth beyond 6 cm in the rat's tissue. Cancer diagnosis based on information about tissue properties from microwave band TAT can potentially be more accurate than has previously been achievable.

Robust optical fiber patch-cords for in vivo optogenetic experiments in rats.

Science.gov (United States)

Trujillo-Pisanty, Ivan; Sanio, Christian; Chaudhri, Nadia; Shizgal, Peter

2015-01-01

In vivo optogenetic experiments commonly employ long lengths of optical fiber to connect the light source (commonly a laser) to the optical fiber implants in the brain. Commercially available patch cords are expensive and break easily. Researchers have developed methods to build these cables in house for in vivo experiments with rodents [1-4]. However, the half-life of those patch cords is greatly reduced when they are used with behaving rats, which are strong enough to break the delicate cable tip and to bite through the optical fiber and furcation tubing. Based on [3] we have strengthened the patch-cord tip that connects to the optical implant, and we have incorporated multiple layers of shielding to produce more robust and resistant cladding. Here, we illustrate how to build these patch cords with FC or M3 connectors. However, the design can be adapted for use with other common optical-fiber connectors. We have saved time and money by using this design in our optical self-stimulation experiments with rats, which are commonly several months long and last four to eleven hours per session. The main advantages are: •Long half-life.•Resistant to moderate rodent bites.•Suitable for long in vivo optogenetic experiments with large rodents.

Effects of low-molecular-weight-chitosan on the adenine-induced chronic renal failure rats in vitro and in vivo

Science.gov (United States)

Zhi, Xuan; Han, Baoqin; Sui, Xianxian; Hu, Rui; Liu, Wanshun

2015-02-01

The effects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigated in vivo and in vitro. Chitosan were hydrolyzed using chitosanase at pH 6-7 and 37° for 24 h to obtain LMWC. In vitro, the effect of LMWC on the proliferation of renal tubular epithelial cells (RTEC) showed that it had no cytotoxic effect and could promote cell growth. For the in vivo experiment, chronic renal failure rats induced by adenine were randomly divided into control group, Niaoduqing group, and high-, medium- and low-dose LMWC groups. For each group, we detected serum creatinine (SCR), blood urea nitrogen (BUN), and total superoxide dismutase (T-SOD), glutathione oxidase (GSH-Px) activities of renal tissue, and obtained the ratio of kidney weight/body weight, pathological changes of kidney. The levels of serum SCR, BUN were higher in the adenine-induced rats than those in the control group, indicating that the rat chronic renal failure model worked successfully. The results after treatment showed that LMWC could reduce the SCR and BUN levels and enhance the activities/levels of T-SOD and GSH-PX in kidney compared to control group. Histopathological examination revealed that adenine-induced renal alterations were restored by LMWC at three tested dosages, especially at the low dosage of 100 mg kg-1 d-1.

In vivo studies of biotin absorption in distal rat intestine

International Nuclear Information System (INIS)

Bowman, B.B.; Rosenberg, I.H.

1986-01-01

The authors have extended their previous studies of biotin absorption in rat proximal jejunum (PJ) to examine biotin absorptive capacity of rat ileum (I) and proximal colon (PC) using in vivo intestinal loop technique. Intestinal loops (2.5 cm) were filled with 0.3 ml of solution containing ( 3 H)-biotin and ( 14 C)-inulin in phosphate buffer, pH 6.5. Biotin absorption was determined on the basis of luminal biotin disappearance after correction for inulin recovery and averaged (pmol/loop-10 min; X +/- SEM). In related experiments, 5-cm loops of PJ, distal I (DI), or PC were filled with 0.5 ml of solution of similar composition (1.0 μM biotin). The abdominal cavity was closed and the rats were allowed to recover from anesthesia, then sacrificed 3 hr after injection. Biotin absorption averaged 96.2% (PJ), 93.2% (DI), and 25.8% (PC) of the dose administered. These differences were reflected in the radioactive biotin content of plasma and intestinal loop, kidney, and liver. These data demonstrate significant biotin absorption in rat DI and PC, as required if the intestinal microflora are to be considered as a source of biotin for the host

Insulin Resistance Is Not Associated with an Impaired Mitochondrial Function in Contracting Gastrocnemius Muscle of Goto-Kakizaki Diabetic Rats In Vivo.

Directory of Open Access Journals (Sweden)

Michael Macia

Full Text Available Insulin resistance, altered lipid metabolism and mitochondrial dysfunction in skeletal muscle would play a major role in type 2 diabetes mellitus (T2DM development, but the causal relationships between these events remain conflicting. To clarify this issue, gastrocnemius muscle function and energetics were investigated throughout a multidisciplinary approach combining in vivo and in vitro measurements in Goto-Kakizaki (GK rats, a non-obese T2DM model developing peripheral insulin resistant without abnormal level of plasma non-esterified fatty acids (NEFA. Wistar rats were used as controls. Mechanical performance and energy metabolism were assessed strictly non-invasively using magnetic resonance (MR imaging and 31-phosphorus MR spectroscopy (31P-MRS. Compared with control group, plasma insulin and glucose were respectively lower and higher in GK rats, but plasma NEFA level was normal. In resting GK muscle, phosphocreatine content was reduced whereas glucose content and intracellular pH were both higher. However, there were not differences between both groups for basal oxidative ATP synthesis rate, citrate synthase activity, and intramyocellular contents for lipids, glycogen, ATP and ADP (an important in vivo mitochondrial regulator. During a standardized fatiguing protocol (6 min of maximal repeated isometric contractions electrically induced at a frequency of 1.7 Hz, mechanical performance and glycolytic ATP production rate were reduced in diabetic animals whereas oxidative ATP production rate, maximal mitochondrial capacity and ATP cost of contraction were not changed. These findings provide in vivo evidence that insulin resistance is not caused by an impairment of mitochondrial function in this diabetic model.

Differential in vivo regulation of TH and DBH mRNA in rat atria by maprotiline and fluoxetine

Directory of Open Access Journals (Sweden)

Spasojević Nataša

2011-01-01

Full Text Available It is well known that antidepressants affect central monoaminergic neurotransmission and that they also modulate hormone release in peripheral tissues. Repeated maprotiline (a noradrenaline reuptake inhibitor and fluoxetine (a serotonin reuptake inhibitor treatment on gene expression of the catecholamine biosynthetic enzymes were examined in rat atria and ventricles in vivo. Maprotiline decreased the gene expression of tyrosine hydroxylase (TH and dopamineβ-hydroxylase (DBH in the rat atrium. Fluoxetine increased gene expression of TH and DBH, but not of phenylethanolamine N-methyltransferase (PNMT. Chronic application of antidepressants did not change the expression of these enzymes in the ventricles. We conclude that repeated administration of fluoxetine enhances gene transcription of TH and DBH and subsequently stimulates noradrenaline synthesis in rat atria in vivo.

An in vivo MRI Template Set for Morphometry, Tissue Segmentation, and fMRI Localization in Rats

Science.gov (United States)

Valdés-Hernández, Pedro Antonio; Sumiyoshi, Akira; Nonaka, Hiroi; Haga, Risa; Aubert-Vásquez, Eduardo; Ogawa, Takeshi; Iturria-Medina, Yasser; Riera, Jorge J.; Kawashima, Ryuta

2011-01-01

Over the last decade, several papers have focused on the construction of highly detailed mouse high field magnetic resonance image (MRI) templates via non-linear registration to unbiased reference spaces, allowing for a variety of neuroimaging applications such as robust morphometric analyses. However, work in rats has only provided medium field MRI averages based on linear registration to biased spaces with the sole purpose of approximate functional MRI (fMRI) localization. This precludes any morphometric analysis in spite of the need of exploring in detail the neuroanatomical substrates of diseases in a recent advent of rat models. In this paper we present a new in vivo rat T2 MRI template set, comprising average images of both intensity and shape, obtained via non-linear registration. Also, unlike previous rat template sets, we include white and gray matter probabilistic segmentations, expanding its use to those applications demanding prior-based tissue segmentation, e.g., statistical parametric mapping (SPM) voxel-based morphometry. We also provide a preliminary digitalization of latest Paxinos and Watson atlas for anatomical and functional interpretations within the cerebral cortex. We confirmed that, like with previous templates, forepaw and hindpaw fMRI activations can be correctly localized in the expected atlas structure. To exemplify the use of our new MRI template set, were reported the volumes of brain tissues and cortical structures and probed their relationships with ontogenetic development. Other in vivo applications in the near future can be tensor-, deformation-, or voxel-based morphometry, morphological connectivity, and diffusion tensor-based anatomical connectivity. Our template set, freely available through the SPM extension website, could be an important tool for future longitudinal and/or functional extensive preclinical studies. PMID:22275894

An in vivo MRI template set for morphometry, tissue segmentation and fMRI localization in rats

Directory of Open Access Journals (Sweden)

Pedro Antonio Valdes Hernandez

2011-11-01

Full Text Available Over the last decade, several papers have focused on the construction of highly detailed mouse high field MRI templates via nonlinear registration to unbiased reference spaces, allowing for a variety of neuroimaging applications such as robust morphometric analyses. However, work in rats has only provided medium field MRI averages based on linear registration to biased spaces with the sole purpose of approximate fMRI localization. This precludes any morphometric analysis in spite of the need of exploring in detail the neuroanatomical substrates of diseases in a recent advent of rat models. In this paper we present a new in vivo rat T2 MRI template set, comprising average images of both intensity and shape, obtained via nonlinear registration. Also, unlike previous rat template sets, we include white and gray matter probabilistic segmentations, expanding its use to those applications demanding prior-based tissue segmentation, e.g. SPM voxel-based morphometry. We also provide a preliminary digitalization of latest Paxinos & Watson atlas for anatomical and functional interpretations within the cerebral cortex. We confirmed that, like with previous templates, forepaw and hindpaw fMRI activations can be correctly localized in the expected atlas structure. To exemplify the use of our new MRI template set, we reported the volumes of brain tissues and cortical structures and probed their relationships with ontogenetic development. Other in vivo applications in the near future can be tensor-, deformation- or voxel-based morphometry, morphological connectivity and diffusion tensor-based anatomical connectivity. Our template set, freely available through the SPM extension website, could be an important tool for future longitudinal and/or functional extensive preclinical studies.

An in vivo MRI Template Set for Morphometry, Tissue Segmentation, and fMRI Localization in Rats.

Science.gov (United States)

Valdés-Hernández, Pedro Antonio; Sumiyoshi, Akira; Nonaka, Hiroi; Haga, Risa; Aubert-Vásquez, Eduardo; Ogawa, Takeshi; Iturria-Medina, Yasser; Riera, Jorge J; Kawashima, Ryuta

2011-01-01

Over the last decade, several papers have focused on the construction of highly detailed mouse high field magnetic resonance image (MRI) templates via non-linear registration to unbiased reference spaces, allowing for a variety of neuroimaging applications such as robust morphometric analyses. However, work in rats has only provided medium field MRI averages based on linear registration to biased spaces with the sole purpose of approximate functional MRI (fMRI) localization. This precludes any morphometric analysis in spite of the need of exploring in detail the neuroanatomical substrates of diseases in a recent advent of rat models. In this paper we present a new in vivo rat T2 MRI template set, comprising average images of both intensity and shape, obtained via non-linear registration. Also, unlike previous rat template sets, we include white and gray matter probabilistic segmentations, expanding its use to those applications demanding prior-based tissue segmentation, e.g., statistical parametric mapping (SPM) voxel-based morphometry. We also provide a preliminary digitalization of latest Paxinos and Watson atlas for anatomical and functional interpretations within the cerebral cortex. We confirmed that, like with previous templates, forepaw and hindpaw fMRI activations can be correctly localized in the expected atlas structure. To exemplify the use of our new MRI template set, were reported the volumes of brain tissues and cortical structures and probed their relationships with ontogenetic development. Other in vivo applications in the near future can be tensor-, deformation-, or voxel-based morphometry, morphological connectivity, and diffusion tensor-based anatomical connectivity. Our template set, freely available through the SPM extension website, could be an important tool for future longitudinal and/or functional extensive preclinical studies.

Effects of phenobarbital pretreatment on the in vivo metabolism of carbaryl in rats

International Nuclear Information System (INIS)

Knight, E.V.; Alvares, A.P.; Chin, B.H.

1987-01-01

Phenobarbital (PB) pretreatment of animals is known to induce the activity of drug-metabolizing enzymes in liver microsomes. Previous studies showed that incubation of carbaryl with microsomes obtained from livers of untreated or PB-treated rats resulted in little or no oxidative metabolism of the substrate. In addition, no spectral interactions were observed when carbaryl was added to hepatic microsomal suspensions. The present study was carried out to determine the effect of PB pretreatment on the in vivo metabolism of carbaryl in rats

Differences in pyrimidine dimer removal between rat skin cells in vitro and in vivo

International Nuclear Information System (INIS)

Mullaart, E.; Lohman, P.H.; Vijg, J.

1988-01-01

Pyrimidine dimers, the most abundant type of DNA lesions induced by ultraviolet light (UV), are rapidly repaired in human skin fibroblasts in vitro. In the same cell type from rats, however, there is hardly any removal of such dimers. To investigate whether this low capacity of rat skin cells to repair lesions in their DNA is an inherent characteristic of this species or an artifact due to cell culturing, we measured the removal of UV-induced pyrimidine dimers from rat epidermal keratinocytes both in vitro and in vivo. Epidermal keratinocytes in vitro were unable to remove any dimers over the first 3 h after UV-irradiation, while only about 20% was removed during a repair period of 24 h. In this respect, these cells were not different from cultured rat fibroblasts. In contrast to the results obtained with keratinocytes in vitro, we observed a rapid repair of pyrimidine dimers in UV-irradiated keratinocytes in vivo over the first 3 h; this rapid repair phase was followed by a much slower repair phase between 3 and 24 h. These results are discussed in terms of the possibility that mammalian cells are able to switch from one DNA repair pathway to another

In vivo image of radioiodinated IVDU and IVFRU in HSV-TK gene tranduced hepatocellular carcinoma bearing buffalo rat

Energy Technology Data Exchange (ETDEWEB)

Lee, Tae Sup; Choi, T. H.; Ahn, S. H.; Woo, K. S.; Chung, W. S.; Lee, S. J.; Choi, C. W. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

2000-07-01

The extent of gene delivery and expression in gene therapy with suicide genes such as herpes simplex virus thymidine kinase (HSV-tk) is assessed with measurement of selective localization of radioiodinated HSV-tk substrates in HSV-tk expressing tumor. We compared n vitro uptake of {sup 125}I-IVDU, IVFRU and in vivo image of HSV-tk gene tranduced hepatocellular carcinoma model. Using H{sub 2}O{sub 2}(hydrogen peroxide), IVDU and IVFRU was radiolabeled as carrier free form. The uptake of {sup 125}I-IVDU IVFRU was determined with increasing incubation periods in MCA-tk and MCA cell line (1X10{sup 6}cell/flask). The cell harvested and counted after incubation of 15, 30, 60, 120, 240, 480 minutes. For estimating accumulation of radiolabelled IVDU, IVFRU in HSV-tk expressing tumor, MCA-tk cells (1 X 10{sup 6}/100 {mu}l) injected intramuscularly into right thigh of buffalo rats. To determine selective localization of radiolabelled IVDU, IVFRU in HSV-tk expressing hepatocellular carcinoma bearing buffalo rats, MCA-tk cells (1X 10{sup 7} cell/100 {mu}l) were injected subcutaneously into both shoulders of buffalo rats. Established tumor mass implanted into liver of buffalo rats using intra-hepatic tumor injection. Two weeks later, {sup 123}I labelled IVDU, IVFRU(7.4 X 10{sup 7}Bq/200 {mu}l) injected intravenously into tail veins of each buffalo rats. Gamma camera used as revealing localization of {sup 123}I-IVDU, IVFRU in MCA-tk cells grafts rats and in vivo image was taken 2 hrs, 24 hrs after injection. radioiodinated IVDU, IVFRU were radiolabeled with {sup 123}I as labeling yield 70%, {sup 125}I as 84%. Two compounds showed minimal uptake in MCA cell line, but in MCA-tk cell line, increased uptake was observed. The ratio of MCA-tk to MCA was up to 116-fold in {sup 125}I-IVDU, up to 37-fold in {sup 125}I-IVFRU at 480 min. The uptake of IVDU was 4 times higher than IVFRU in MCA-tk cells. Gamma camera images of HSV-tk gene tranduced MCA tumor showed accumulation of {sup 123}I

In vivo longitudinal micro-CT study of bent long limb bones in rat offspring.

Science.gov (United States)

De Schaepdrijver, Luc; Delille, Peter; Geys, Helena; Boehringer-Shahidi, Christian; Vanhove, Christian

2014-07-01

Micro-computed X-ray tomography (micro-CT) has been reported as a reliable method to assess ex vivo rat and rabbit fetal skeletons in embryo-fetal developmental toxicity studies. Since micro-CT is a non-invasive imaging modality it has the potential for longitudinal, in vivo investigation of postnatal skeletal development. This is the first paper using micro-CT to assess the reversibility of drug-induced bent long bones in a longitudinal study from birth to early adulthood in rat offspring. Analysis of the scans obtained on postnatal Day 0, 7, 21 and 80 showed complete recovery or repair of the bent long limb bones (including the scapula) within the first 3 weeks. When assessing risk the ability to demonstrate recovery is highly advantageous when interpreting such transient skeletal change. In summary, in vivo micro-CT of small laboratory animals can aid in non-clinical safety assessment, particularly for specific mechanistic purposes or to address a particular concern in developmental biology. Copyright © 2014 Elsevier Inc. All rights reserved.

Cortical substrate oxidation during hyperketonemia in the fasted anesthetized rat in vivo.

Science.gov (United States)

Jiang, Lihong; Mason, Graeme F; Rothman, Douglas L; de Graaf, Robin A; Behar, Kevin L

2011-12-01

Ketone bodies are important alternate brain fuels, but their capacity to replace glucose and support neural function is unclear. In this study, the contributions of ketone bodies and glucose to cerebral cortical metabolism were measured in vivo in halothane-anesthetized rats fasted for 36 hours (n=6) and receiving intravenous [2,4-(13)C(2)]-D-β-hydroxybutyrate (BHB). Time courses of (13)C-enriched brain amino acids (glutamate-C4, glutamine-C4, and glutamate and glutamine-C3) were measured at 9.4 Tesla using spatially localized (1)H-[(13)C]-nuclear magnetic resonance spectroscopy. Metabolic rates were estimated by fitting a constrained, two-compartment (neuron-astrocyte) metabolic model to the (13)C time-course data. We found that ketone body oxidation was substantial, accounting for 40% of total substrate oxidation (glucose plus ketone bodies) by neurons and astrocytes. D-β-Hydroxybutyrate was oxidized to a greater extent in neurons than in astrocytes (≈ 70:30), and followed a pattern closely similar to the metabolism of [1-(13)C]glucose reported in previous studies. Total neuronal tricarboxylic acid cycle (TCA) flux in hyperketonemic rats was similar to values reported for normal (nonketotic) anesthetized rats infused with [1-(13)C]glucose, but neuronal glucose oxidation was 40% to 50% lower, indicating that ketone bodies had compensated for the reduction in glucose use.

Use of Terbinafine in Mouse and Rat Models of Pneumocystis carinii Pneumonia

Science.gov (United States)

Walzer, Peter D.; Ashbaugh, Alan

2002-01-01

Terbinafine, an allylamine used to treat onychomycosis, has been reported to be active against rat Pneumocystis carinii in vitro and in vivo. By contrast, our in vitro data showed that the 50% inhibitory concentration of terbinafine against rat P. carinii is 3.7 μg/ml, a level that cannot be clinically achieved in serum. In the present study, terbinafine administered orally at doses of 20 to 400 mg/kg/day and 50 to 250 mg/kg/day was ineffective therapy for mouse and rat models of pneumocystosis, respectively. These results emphasize the complexities of P. carinii drug testing and the need for caution before considering studies in humans. PMID:11796365

Evaluation of [{sup 11}C]-DAA1106 for imaging and quantification of neuroinflammation in a rat model of herpes encephalitis

Energy Technology Data Exchange (ETDEWEB)

Doorduin, Janine [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, PO Box 30.001, 9700 RB Groningen (Netherlands)], E-mail: j.doorduin@ngmb.umcg.nl; Klein, Hans C. [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, PO Box 30.001, 9700 RB Groningen (Netherlands); University Center of Psychiatry, University Medical Center Groningen, University of Groningen, PO Box 30.001, 9700 RB Groningen (Netherlands); Jong, Johan R. de; Dierckx, Rudi A.; Vries, Erik F.J. de [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, PO Box 30.001, 9700 RB Groningen (Netherlands)

2010-01-15

Introduction: Many neurological and psychiatric disorders are associated with neuroinflammation. Positron emission tomography (PET) with [{sup 11}C]-PK11195 can be used to study neuroinflammation in these disorders. However, [{sup 11}C]-PK11195 may not be sensitive enough to visualize mild neuroinflammation. As a potentially more sensitive PET tracer for neuroinflammation, [{sup 11}C]-N-(2,5-dimethoxybenzyl)-N-(4-fluoro-2-phenoxyphenyl)-acetamide (DAA1106) was evaluated in a rat model of herpes encephalitis. Methods: Male Wistar rats were intranasally inoculated with HSV-1 (HSE) or phosphate-buffered saline (control). At Day 6 or Day 7 after inoculation, small-animal [{sup 11}C]-DAA1106 PET scans were acquired, followed by ex vivo biodistribution. Arterial blood sampling was performed for quantification of uptake. Results: In HSE rats, a significantly higher ex vivo, but not in vivo, uptake of [{sup 11}C]-DAA1106 was found in almost all examined brain areas (24-71%, P<.05), when compared to control rats. Pretreatment with unlabeled PK11195 effectively reduced [{sup 11}C]-DAA1106 uptake in HSE rats (54-84%; P<.001). The plasma and brain time-activity curves showed rapid uptake of [{sup 11}C]-DAA1106 into tissue. The data showed a good fit to the Logan analysis but could not be fitted to a two-tissue compartment model. Conclusions: [{sup 11}C]-DAA1106 showed a high and specific ex vivo uptake in the encephalitic rat brain. However, neuroinflammation could not be demonstrated in vivo by [{sup 11}C]-DAA1106 PET. Quantification of the uptake of [{sup 11}C]-DAA1106 using plasma sampling is not optimal, due to rapid tissue uptake, slow tissue clearance and low plasma activity.

In Vivo Monitoring of Pancreatic β-Cells in a Transgenic Mouse Model

Directory of Open Access Journals (Sweden)

Steven J. Smith

2006-04-01

Full Text Available We generated a transgenic mouse model (RIP-luc for the in vivo monitoring of pancreatic islet mass and function in response to metabolic disease. Using the rat insulin promoter fused to firefly luciferase, and noninvasive technology to detect luciferase activity, we tracked changes in reporter signal during metabolic disease states and correlated the changes in luciferase signal with metabolic status of the mouse. Transgene expression was found to be specific to the pancreatic islets in this transgenic model. Basal transgene expression was tracked in male and female mice fed either a chow or a high-fat diet and in response to treatment with streptozotocin. Pancreatic bioluminescent signal increased in mice fed a high-fat diet compared with chow-fed animals. In a model of chemically induced diabetes, the bioluminescent signal decreased in accordance with the onset of diabetes and reduction of islet β-cell number. Preliminary studies using islets transplanted from this transgenic model suggest that in vivo image analysis can also be used to monitor transplanted islet viability and survival in the host. This transgenic model is a useful tool for in vivo studies of pancreatic β-cells and as a donor for islet transplantation studies.

In vivo analysis of tissue by Raman microprobe: examination of human skin lesions and esophagus Barrett's mucosa on an animal model

Science.gov (United States)

Tfayli, Ali; Piot, Olivier; Derancourt, Sylvie; Cadiot, Guillaume; Diebold, Marie D.; Bernard, Philippe; Manfait, Michel

2006-02-01

In the last few years, Raman spectroscopy has been increasingly used for the characterization of normal and pathological tissues. A new Raman system, constituted of optic fibers bundle coupled to an axial Raman spectrometer (Horiba Jobin Yvon SAS), was developed for in vivo investigations. Here, we present in vivo analysis on two tissues: human skin and esophagus mucosa on a rat model. The skin is a directly accessible organ, representing a high diversity of lesions and cancers. Including malignant melanoma, basal cell carcinoma and the squamous cell carcinoma, skin cancer is the cancer with the highest incidence worldwide. Several Raman investigations were performed to discriminate and classify different types of skin lesions, on thin sections of biopsies. Here, we try to characterize in vivo the different types of skin cancers in order to be able to detect them in their early stages of development and to define precisely the exeresis limits. Barrett's mucosa was also studied by in vivo examination of rat's esophagus. Barrett's mucosa, induced by gastro-esophageal reflux, is a pretumoral state that has to be carefully monitored due to its high risk of evolution in adenocarcinoma. A better knowledge of the histological transformation of esophagus epithelium in a Barrett's type will lead to a more efficient detection of the pathology for its early diagnosis. To study these changes, an animal model (rats developing Barrett's mucosa after duodenum - esophagus anastomosis) was used. Potential of vibrational spectroscopy for Barrett's mucosa identification is assessed on this model.

Protective properties of plasma of burnt and irradiated rats against lethal effect of endotoxins in vivo

Energy Technology Data Exchange (ETDEWEB)

Budagov, R S; Chureyeva, L N

1984-10-01

The purpose of this work was to estimate protective properties of plasma in disease with increased endotoxemia. Burns and acute radiation sickness were used as models of suppression of physiological mechanisms of detoxication. Experiments were performed on male Wistar rats and mice, which received 3rd degree burns over 15% of the body surface, whole body gamma irradiation at 7.5 Gr or both. At 3 hours, 3, 7 and 12 days after the exposure the animals were decapitated and blood collected. The irradiated mice received 0.2 ml endotoxin intraperitoneally, 1.0 ml freshly prepared rat plasma, then the lethality of the mice in 24 hours was observed. It was found that the plasma of intact rats was capable of decreasing the lethal effects of S. typhimurium and E. coli endotoxins in vivo in mice. Deep skin burns, acute radiation sickness and the combined effects of radiation and thermal injury did not change this phenomenon. The plasma of the experimental rats retained the protective properties at various periods of time after the thermal, radiation and combined exposures. The functioning of the humoral detoxication mechanism is radioresistant, indirectly indicating the nonimmunoglobulin nature of endotoxin inactivators. 19 references.

The in vivo pharmacokinetics, tissue distribution and excretion investigation of mesaconine in rats and its in vitro intestinal absorption study using UPLC-MS/MS.

Science.gov (United States)

Liu, Xiuxiu; Tang, Minghai; Liu, Taohong; Wang, Chunyan; Tang, Qiaoxin; Xiao, Yaxin; Yang, Ruixin; Chao, Ruobing

2017-12-27

1. Mesaconine, an ingredient from Aconitum carmichaelii Debx., has been proven to have cardiac effect. For further development and better pharmacological elucidation, the in vivo process and intestinal absorptive behavior of mesaconine should be investigated comprehensively. 2. An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitation of mesaconine in rat plasma, tissue homogenates, urine and feces to investigate the in vivo pharmacokinetic profiles, tissue distribution and excretion. The intestinal absorptive behavior of mesaconine was investigated using in vitro everted rat gut sac model. 3. Mesaconine was well distributed in tissues and a mass of unchanged form was detected in feces. It was difficultly absorbed into blood circulatory system after oral administration. The insufficient oral bioavailability of mesaconine may be mainly attributed to its low intestinal permeability due to a lack of lipophilicity. The absorption of mesaconine in rat's intestine is a first-order process with the passive diffusion mechanism.

4-[[sup 123]I]iodospiperone as a ligand for dopamine DA receptors: in vitro and in vivo experiments in a rat model

Energy Technology Data Exchange (ETDEWEB)

Krogt, J.A. van der; Valkenburg, C F.M. van; Pauwels, E K.J.; Buruma, O J.S. [Rijksuniversiteit Leiden (Netherlands); Reiffers, S [Hospital De Weezenlanden, Zwolle (Netherlands); Doremalen, P.A.P.M. van; Wijnhoven, G [Cygne, Eindhoven (Netherlands)

1992-10-01

Radioiodinated spiperone is of interest for dopamine (DA) receptor studies in the living human brain by single photon emission computed tomography (SPECT). Simulated by data obtained with [[sup 11]C]-N-methyl-spiperone, we synthesized 4-[[sup 123]I]iodospiperone and investigated the in vitro binding characteristics of this ligand to the striatal membrane of the rat and the in vivo distribution over various rat brain regions. The in vitro binding experiments showed that this radioligand displays about 10 times less affinity for the DA receptor than spiperone and specific binding, as shown with [[sup 3]H]spiperone, was not observed. Displacement by butaclamol was not observed. The in vivo studies demonstrated that both 4-[[sup 123]I]iodospiperone and [[sup 3]H]spiperone concentrate in striatal tissue, respectively, 1.9 and 3.5 times as high as in cerebellar tissue. Haloperidol pretreatment largely prevented this accumulation. In view of the obtained target-to-non-target ratios we believe, however, that this accumulation in brain areas rich DA-receptors does not offer prospects for clinical receptor imaging with SPECT. (Author).

In Vivo Kinetics of Mesenchymal Stem Cells Transplanted into the Knee Joint in a Rat Model Using a Novel Magnetic Method of Localization.

Science.gov (United States)

Ikuta, Yasunari; Kamei, Naosuke; Ishikawa, Masakazu; Adachi, Nobuo; Ochi, Mitsuo

2015-10-01

We have developed a magnetic system for targeting cells in minimally invasive cell transplantation. Magnetically labeled MSCs (m-MSCs) with nanoscale iron particles can be guided into the desired region by magnetic force from an extracorporeal device. We reported that magnetic targeting of m-MSCs enhances cartilage repair in a mini-pig model. However, the detailed kinetics of these magnetically targeted m-MSCs remain unknown. For clinical use, this aspect should be clarified from a safety standpoint. We therefore investigated the spatial and temporal distribution of the fluorescently-labeled m-MSCs transplanted into the knee joint using in vivo fluorescence combined with three-dimensional computed tomographic imaging in a rat model. Although the intraarticularly injected m-MSCs were spread throughout the joint cavity in the absence of magnetic force, the magnetic force caused the injected m-MSCs to accumulate around the chondral lesion. Further examinations including ex vivo imaging, histological assessments and reverse transcription polymerase chain reaction revealed that transplanted MSCs were not present in any major organs after intraarticular administration, regardless of magnetic targeting. Our data suggest that m-MSCs can be accumulated efficiently into a chondral lesion using our magnetic targeting system, while none of the intraarticularly transplanted MSCs migrate to other major organs. © 2015 Wiley Periodicals, Inc.

[Infecting glial cells with antimony resistant Leishmania tropica: A new ex-vivo model].

Science.gov (United States)

Zorbozan, Orçun; Harman, Mehmet; Evren, Vedat; Erdoğan, Mümin Alper; Kılavuz, Aslı; Tunalı, Varol; Çavuş, İbrahim; Yılmaz, Özlem; Özbilgin, Ahmet; Turgay, Nevin

2018-01-01

Leishmaniasis is a vector-borne zoonotic disease that shows different clinical features like cutaneous, mucocutaneous, visceral and viscerotropic forms. The protocols used in the treatment of leishmaniasis are toxic and have many limitations during administration. One of the limitations of treatment is the resistance against the protocols in practice. There is also a need to define new treatment options especially for resistant patients. Ex-vivo models using primary cell cultures may be a good source for evaluating new drug options in patients with antimony resistance, in addition to in-vitro and in-vivo studies. In this study, it was aimed to define a new ex-vivo culture model to evaluate treatment options in patients with cutaneous leishmaniasis who did not respond to treatment. In our experimental model of ex-vivo infection, Leishmania tropica promastigotes isolated from a case previously diagnosed with cutaneous leishmaniasis were used. The primary astroglial cell culture used for the ex-vivo model was prepared from 2-3 days old neonatal Sprague Dawley rat brains under sterile conditions by the modification McCarthy's method. The astroglia cells, which reached sufficient density, were infected with antimony resistant L.tropica promastigotes. After 24 hours of incubation, the supernatant on the cells were collected, the cell culture plate was dried at room temperature, then fixed with methyl alcohol and stained with Giemsa to search for L.tropica amastigotes. Amastigotes were intensely observed in glia cells in primary cell cultures infected with L.tropica promastigotes. No promastigotes were seen on Giemsa stained preparations of the precipitates prepared from the bottom sediment after the centrifugation of the liquid medium removed from the infected plates. In this study, promastigotes from a cutaneous leishmaniasis patient unable to respond to pentavalent antimony therapy were shown to infect rat glia cells and converted to amastigote form. This amastigote

Structural layers of ex vivo rat hippocampus at 7T MRI.

Directory of Open Access Journals (Sweden)

Jeanine Manuella Kamsu

Full Text Available Magnetic resonance imaging (MRI applied to the hippocampus is challenging in studies of the neurophysiology of memory and the physiopathology of numerous diseases such as epilepsy, Alzheimer's disease, ischemia, and depression. The hippocampus is a well-delineated cerebral structure with a multi-layered organization. Imaging of hippocampus layers is limited to a few studies and requires high magnetic field and gradient strength. We performed one conventional MRI sequence on a 7T MRI in order to visualize and to delineate the multi-layered hippocampal structure ex vivo in rat brains. We optimized a volumic three-dimensional T2 Rapid Acquisition Relaxation Enhancement (RARE sequence and quantified the volume of the hippocampus and one of its thinnest layers, the stratum granulare of the dentate gyrus. Additionally, we tested passive staining by gadolinium with the aim of decreasing the acquisition time and increasing image contrast. Using appropriated settings, six discrete layers were differentiated within the hippocampus in rats. In the hippocampus proper or Ammon's Horn (AH: the stratum oriens, the stratum pyramidale of, the stratum radiatum, and the stratum lacunosum moleculare of the CA1 were differentiated. In the dentate gyrus: the stratum moleculare and the stratum granulare layer were seen distinctly. Passive staining of one brain with gadolinium decreased the acquisition time by four and improved the differentiation between the layers. A conventional sequence optimized on a 7T MRI with a standard receiver surface coil will allow us to study structural layers (signal and volume of hippocampus in various rat models of neuropathology (anxiety, epilepsia, neurodegeneration.

Validation of housekeeping genes for quantitative real-time PCR in in-vivo and in-vitro models of cerebral ischaemia

Directory of Open Access Journals (Sweden)

Serena Joaquín

2009-06-01

Full Text Available Abstract Background Studies of gene expression in experimental cerebral ischaemia models can contribute to understanding the pathophysiology of brain ischaemia and to identifying prognostic markers and potential therapeutic targets. The normalization of relative qRT-PCR data using a suitable reference gene is a crucial prerequisite for obtaining reliable conclusions. No validated housekeeping genes have been reported for the relative quantification of the mRNA expression profile activated in in-vitro ischaemic conditions, whereas for the in-vivo model different reference genes have been used. The present study aims to determine the expression stability of ten housekeeping genes (Gapdh, β2m, Hprt, Ppia, Rpl13a, Oaz1, 18S rRNA, Gusb, Ywhaz and Sdha to establish their suitability as control genes for in-vitro and in-vivo cerebral ischaemia models. Results The expression stability of the candidate reference genes was evaluated using the 2-ΔC'T method and ANOVA followed by Dunnett's test. For the in-vitro model using primary cultures of rat astrocytes, all genes analysed except for Rpl13a and Sdha were found to have significantly different levels of mRNA expression. These different levels were also found in the case of the in-vivo model of pMCAO in rats except for Hprt, Sdha and Ywhaz mRNA, where the expression did not vary. Sdha and Ywhaz were identified by geNorm and NormFinder as the two most stable genes. Conclusion We have validated endogenous control genes for qRT-PCR analysis of gene expression in in-vitro and in-vivo cerebral ischaemia models. For normalization purposes, Rpl13a and Sdha are found to be the most suitable genes for the in-vitro model and Sdha and Ywhaz for the in-vivo model. Genes previously used as housekeeping genes for the in-vivo model in the literature were not validated as good control genes in the present study, showing the need for careful evaluation for each new experimental setup.

Spinal cord dopamine D2/D3 receptors: in vivo and ex vivo imaging in the rat using 18F/11C-fallypride

International Nuclear Information System (INIS)

Kaur, Jasmeet; Khararjian, Armen; Coleman, Robert A.; Constantinescu, Cristian C.; Pan, Min-Liang; Mukherjee, Jogeshwar

2014-01-01

Objectives: The spinal cord is known to be innervated with dopaminergic cells with catecholaminergic projections arising from the medulla and pons and dopaminergic transmission in the spinal cord is vital for sensory and motor function. Our goal was to evaluate and compare the imaging capability of dopamine D2/D3 receptors in the rat spinal cord using PET ligands 18 F-fallypride and 11 C-fallypride. Methods: Male Sprague–Dawley rats were used in all in vitro and in vivo studies. Spinal cord and brain sections were used for in vitro autoradiography and ex vivo autoradiography. For in vivo studies animals received a 18 F-fallypride scan or a 11 C-fallypride PET scan. The spinal cord and the brain were then harvested, flash-frozen and imaged ex vivo. For in vivo analysis Logan plots with cerebellum as a reference was used to evaluate binding potentials (BP). Tissue ratios were used for ex vivo analysis. Drug effects were evaluated using clozapine, haloperidol and dopamine were evaluated on spinal cord sections in vitro. Results: In vitro studies showed 18 F-fallypride binding to superficial dorsal horn (SDH), dorsal horn (DH), ventral horn (VH) and the pars centralis (PC). In the cervical section, the greatest amount of binding appeared to be in the SDH. Ex vivo studies showed approximately 6% of 18 F-fallypride in SDH compared to that observed in the striatum. In vivo analysis of both 18 F-fallypride and 11 C-fallypride in the spinal cord were comparable to that in the extrastriatal regions. Haloperidol and clozapine displaced more than 75% of the 18 F-fallypride in spinal cord sections. Conclusions: Our studies showed 18 F-fallypride and 11 C-fallypride binding in the spinal cord in vitro and in vivo. The binding pattern correlates well with the known distribution of dopamine D2/D3 receptors in the spinal cord

Optical coherence tomography based microangiography for quantitative monitoring of structural and vascular changes in a rat model of acute uveitis in vivo: a preliminary study

Science.gov (United States)

Choi, Woo June; Pepple, Kathryn L.; Zhi, Zhongwei; Wang, Ruikang K.

2015-01-01

Uveitis models in rodents are important in the investigation of pathogenesis in human uveitis and the development of appropriate therapeutic strategies for treatment. Quantitative monitoring of ocular inflammation in small animal models provides an objective metric to assess uveitis progression and/or therapeutic effects. We present a new application of optical coherence tomography (OCT) and OCT-based microangiography (OMAG) to a rat model of acute anterior uveitis induced by intravitreal injection of a killed mycobacterial extract. OCT/OMAG is used to provide noninvasive three-dimensional imaging of the anterior segment of the eyes prior to injection (baseline) and two days post-injection (peak inflammation) in rats with and without steroid treatments. OCT imaging identifies characteristic structural and vascular changes in the anterior segment of the inflamed animals when compared to baseline images. Characteristics of inflammation identified include anterior chamber cells, corneal edema, pupillary membranes, and iris vasodilation. In contrast, no significant difference from the control is observed for the steroid-treated eye. These findings are compared with the histology assessment of the same eyes. In addition, quantitative measurements of central corneal thickness and iris vessel diameter are determined. This pilot study demonstrates that OCT-based microangiography promises to be a useful tool for the assessment and management of uveitis in vivo.

Effects of chlorphentermine and phentermine on the pulmonary disposition of 5-hydroxytryptamine in the rat in vivo

International Nuclear Information System (INIS)

Morita, T.; Mehendale, H.M.

1983-01-01

This study was designed to examine whether chlorphentermine (CP) affects pulmonary disposition of 5-hydroxytryptamine (5-HT) in rat in vivo. Further, the effects of CP were compared with those of phentermine (P), the nonchlorinated congener. The right jugular vein and left carotid artery of male Sprague-Dawley rats were cannulated and fresh saline solution containing 150 micrograms indocyanine green and a mixture of labeled and unlabeled 5-HT was injected into the jugular vein, and arterial blood samples were collected for 20 s. In order to compare the effect of CP and P on pulmonary disposition of 5-HT, 2.6 nmol [ 14 C]-5-HT was employed for in vivo single-pass experiments. Each animal was used for 2 in vivo single-pass experiments. After the first experiment, which served as a control, animals received an indicated dose of CP or P, to commence the second ''drug-treated'' in vivo experiment. Pulmonary clearance of 5-HT was inhibited by prior administration of CP (1 mg/kg) by 42%, whereas at the highest dose (20 mg/kg) P inhibited 5-HT clearance by only 25%. Pulmonary accumulation of CP was greater than P at higher doses, and the inhibition of 5-HT clearance correlated with the pulmonary accumulation of these drugs. In addition to the in vivo demonstration of the CP inhibition of pulmonary clearance of 5-HT in the rat, these studies also demonstrate a higher affinity of the lung tissue for CP than for P and a greater propensity for the impairment of pulmonary 5-HT clearance

The effect of ionizing radiations on rat serum albumin on in vivo and in vitro

International Nuclear Information System (INIS)

Portakal, S.

1984-01-01

The effect of ionizing radiations on rat serum albumin was studied on in vivo and in vitro. Male rats (rattus norvegicus) were exposed to 225 roentgen wholebody X-irradiation on in vivo experiments. Time-course effects of irradiation on albumin level examined at immediately, 2.5 hours and 3 days after irradiation. Albumin level decreased above control level 2.5 hours after irradiation and rised within 3 days reaching control level. Pre-albumin/albumin ratio enhanced after x-irradiation. Aqueous solutions (0.5 percent) of rat serum albumin was exposed to various doses (0.2, 0.5, 1.0 and 1.9 Mrad) of 60 Co gamma irradiation on in vitro experiments. Results showed that electrophoretic mobility of serum albumin decreased after gamma irradiation. No significant change in albumin UV absorption spectrum was observed at 0.2, 0.5, 1.0 and 1.9 Mrad doses. Albumin becomes progressively less soluble in water as the radiation doses is increased. Radiation induced transformation into insoluble albumin agregates and scission products. (author)

Long-term reproducibility of in vivo measures of specific binding of radioligands in rat brain

Energy Technology Data Exchange (ETDEWEB)

Kilbourn, Michael R. E-mail: mkilbour@umich.edu

2004-07-01

The long-term reproducibility of measures of in vivo specific binding of radiolabeled forms of (+)-{alpha}-dihydrotetrabenazine (DTBZ) and d-threo-methylphenidate (MPH) in rat brain was examined. All studies were done using a consistent bolus plus infusion protocol and calculation of equilibrium distribution volume ratios (DVR). Over a period of eight years striatal DVR values for DTBZ binding to the vesicular monoamine transporter 2 (VMAT2) in young adult (8-10 wks old) rats showed very good reproducibility (3.62{+-}0.33, N=35). Equivalent values were obtained using either tritiated or carbon-11 labeled DTBZ, and were irrespective of sex of animals. Older animals (78 wks old) showed losses (-45%) of specific binding. Striatal binding of MPH to the dopamine transporter (DAT) showed a similar reproducibility over a five year period (DVR=2.17{+-}0.39, N=52), again irrespective of radionuclide or sex. These studies demonstrate that use of a consistent in vivo technique can provide reliable measures of specific binding of radioligands to high affinity sites in the rat brain.

An in-vitro–in-vivo model for the transdermal delivery of cholecalciferol for the purposes of rodent management

Science.gov (United States)

Davies, J.; Ingham, A.

2015-01-01

The natural selection of anticoagulant resistant rats has resulted in a need for an alternative to anticoagulant rodenticides which differs in both active ingredient and in the method of dosing. Cholecalciferol toxicity to rodents using the dermal route is demonstrated using a variety of penetration enhancing formulations in two in-vitro models and finally in-vivo. A 1 ml dose of 50/50 (v/v) DMSO/ethanol containing 15% (v/v) PEG 200 and 20% (w/v) cholecalciferol was judged as ‘sufficiently effective’ in line with the European Union’s Biocidal Products Regulation (No. 528/2012) during in-vivo studies. This dose was found to cause 100% mortality in a rat population in 64.4 h (±22 h). PMID:25835266

Skeletal growth and long-term bone turnover after enterocystoplasty in a chronic rat model

DEFF Research Database (Denmark)

Gerharz, E.W.; Gasser, J.A.; Mosekilde, Li.

2003-01-01

OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment, colocystopl......OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion.MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment...... mass ex vivo.RESULTS: Most (90%) of the rats survived the study period (8 months); six rats died from bowel obstruction at the level of the entero-anastomosis and four had to be killed because of persistent severe diarrhoea. Vital intestinal mucosa was found in all augmented bladders. There were...... no differences in bone length and volume. Loss of bone mass was almost exclusively in rats with ileocystoplasty and resection of the ileocaecal segment (-37.5%, pQCT, P

In vivo genotoxicity assessment in rats exposed to Prestige-like oil by inhalation.

Science.gov (United States)

Valdiglesias, Vanessa; Kiliç, Gözde; Costa, Carla; Amor-Carro, Óscar; Mariñas-Pardo, Luis; Ramos-Barbón, David; Méndez, Josefina; Pásaro, Eduardo; Laffon, Blanca

2012-01-01

One of the largest oil spill disasters in recent times was the accident of the oil tanker Prestige in front of the Galician coast in 2002. Thousands of people participated in the cleanup of the contaminated areas, being exposed to a complex mixture of toxic substances. Acute and prolonged respiratory symptoms and genotoxic effects were reported, although environmental exposure measurements were restricted to current determinations, such that attribution of effects observed to oil exposure is difficult to establish. The aim of this study was to analyze peripheral blood leukocytes (PBL) harvested from a rat model of subchronic exposure to a fuel oil with similar characteristics to that spilled by the Prestige tanker, in order to determine potential genotoxic effects under strictly controlled, in vivo exposure. Wistar Han and Brown Norway rats were exposed to the oil for 3 wk, and micronucleus test (MN) and comet assay, standard and modified with 8-oxoguanine DNA glycosylase (OGG1) enzyme, were employed to assess genotoxicity 72 h and 15 d after the last exposure. In addition, the potential effects of oil exposure on DNA repair capacity were determined by means of mutagen sensitivity assay. Results obtained from this study showed that inhalation oil exposure induced DNA damage in both Brown Norway and Wistar Han rats, especially in those animals evaluated 15 d after exposure. Although alterations in the DNA repair responses were noted, the sensitivity to oil substances varied depending on rat strain. Data support previous positive genotoxicity results reported in humans exposed to Prestige oil during cleanup tasks.

Vasomotor function in rat arteries after ex vivo and intragastric exposure to food-grade titanium dioxide and vegetable carbon particles

DEFF Research Database (Denmark)

Jensen, Ditte Marie; Christophersen, Daniel Vest; Sheykhzade, Majid

2018-01-01

-grade particle exposure on vasomotor function and systemic oxidative stress in an ex vivo study and intragastrically exposed rats.Methods: In an ex vivo study, aorta rings from naive Sprague-Dawley rats were exposed for 30 min to food-grade TiO2 (E171), benchmark TiO2 (Aeroxide P25), food-grade vegetable carbon...... (E153) or benchmark carbon black (Printex 90). Subsequently, the vasomotor function was assessed in wire myographs. In an in vivo study, lean Zucker rats were exposed intragastrically once a week for 10 weeks to vehicle, E171 or E153. Doses were comparable to human daily intake. Vasomotor function...... no differences between groups.Conclusion: Gastrointestinal tract exposure to E171 and E153 was associated with modest albeit statistically significant alterations in the vasocontraction and vasorelaxation responses. Direct particle exposure to aorta rings elicited a similar type of response. The vasomotor...

In vivo distribution of Tc-99m labeled recombinant tissue-type plasminogen activator in control and thrombus-bearing rats

International Nuclear Information System (INIS)

Tsukamoto, Eriko

1992-01-01

In vivo distribution of Tc-99m labeled recombinant tissue-type plasminogen activator (Tc-99m-rt-PA) was studied in control rats and thrombus-bearing rats. To compare fibrin binding in vivo with that in vitro, Tc-99m-rt-PA binding to fibrin gel in vitro was also imaged. Rapid blood clearance and accumulation into the liver and kidneys were observed in both control and thrombus-bearing rats. Accumulation in the stomach, which indicates instability of labeled rt-PA in vivo, was very low until two hours after injection. Tc-99m-rt-PA accumulation in the clots was higher than that in skeletal and heart muscles, although it was lower than in blood, liver, and kidneys. Administration of aprotinin, an antifibrinolytic agent, significantly prolonged clot accumulation of Tc-99m-rt-PA at 30 minutes after injection. These results suggest that fibrinolysis is responsible for the low rt-PA concentration in the clots. A scintigram of a thrombus-bearing rat demonstrated increased radioactivity at the clot forming site. On the other hand, Tc-99m-labeled human albumin, which was used as a control, was not accumulated in the clot. Tc-99m-rt-PA binding to fibrin gel in vitro was clearly imaged. By comparison, in vivo fibrin binding of Tc-99m-rt-PA was much lower than in vitro. The reasons for low thrombus uptake in vivo may be: (1) biochemical inactivation of extrinsically administered rt-PA by t-PA inhibitor; (2) fibrinolysis by rt-PA activated plasminogen. Overcoming these limitations will enable Tc-99m-rt-PA to reach the stage of clinical trials. (author)

MR angiography, MR imaging and proton MR spectroscopy in-vivo assessment of skeletal muscle ischemia in diabetic rats.

Directory of Open Access Journals (Sweden)

Stefano Delli Pizzi

Full Text Available To prospectively evaluate the feasibility of using magnetic resonance (MR techniques for in-vivo assessing a rat diabetic model of limb ischemia. Unilateral hind limb ischemia was induced by ligation of the iliac-femoral artery in male streptozotocin-treated and non-diabetic control rats. Four weeks after ligation, rats underwent MR Angiography (MRA, T(1-weighted and Short Time Inversion Recovery (STIR sequences and muscle Proton MR Spectroscopy ((1H-MRS on both hind limbs. After MR examinations, immunoblotting and immunofluorescence analysis were performed. MRA showed a signal void due to flow discontinuation distal to the artery ligation. T(1-weighted and STIR images showed, respectively, the presence of tissue swelling (p = 0.018 for non-diabetic; p = 0.027 for diabetic rats and signal hyperintensity in tissue affected by occlusion. Mean total creatine/water for the occluded limb was significantly lower than for the non-occluded limbs in both non-diabetic (5.46×10(-4 vs 1.14×10(-3, p = 0.028 and diabetic rats (1.37×10(-4 vs 1.10×10(-3; p = 0.018. MR Imaging and (1H-MRS changes were more pronounced in diabetic than in non-diabetic occluded limbs (p = 0.032. MR findings were confirmed by using histological findings. Combined MR techniques can be used to demonstrate the presence of structural and metabolic changes produced by iliac-femoral artery occlusion in rat diabetic model of limb ischemia.

Effect of irradiation on gene expression of rat liver adhesion molecules. In vivo and in vitro studies

International Nuclear Information System (INIS)

Moriconi, Federico; Malik, Ihtzaz; Ahmad, Ghayyor; Dudas, Joszef; Ramadori, Giuliano; Rave-Fraenk, Margret; Vorwerk, Hilke; Hille, Andrea; Hess, Clemens Friedrich; Christiansen, Hans

2009-01-01

Background and purpose: Migration of leukocytes into tissue is a key element of innate and adaptive immunity. An animal study showed that liver irradiation, in spite of induction of chemokine gene expression, does not lead to recruitment of leukocytes into the parenchyma. The aim of this study was to analyze gene expression of adhesion molecules, which mediate leukocyte recruitment into organs, in irradiated rat liver in vivo and rat hepatocytes in vitro. Material and methods: Rat livers in vivo were irradiated selectively at 25 Gy. Isolated hepatocytes in vitro were irradiated at 8 Gy. RNA extracted within 48 h after irradiation in vivo and in vitro was analyzed by real-time PCR (polymerase chain reaction) and Northern blot. Adhesion molecule concentration in serum was measured by ELISA (enzyme-linked immunosorbent assay). Cryostat sections of livers were used for immunohistology. Results: Significant radiation-induced increase of ICAM-1 (intercellular adhesion molecule-1), VCAM-1 (vascular cell adhesion molecule-1), JAM-1 (junctional adhesion molecule-1), β 1 -integrin, β 2 -integrin, E-cadherin, and P-selectin gene expression could be detected in vivo, while PECAM-1 (platelet-endothelial cell adhesion molecule-1) gene expression remained unchanged. In vitro, β 1 -integrin, JAM-1, and ICAM-2 showed a radiation-induced increased expression, whereas the levels of P-selectin, ICAM-1, PECAM-1, VCAM-1, Madcam-1 (mucosal addressin cell adhesion molecule-1), β 2 -integrin, and E-cadherin were downregulated. However, incubation of irradiated hepatocytes with either tumor necrosis factor-(TNF-)α, interleukin-(IL-)1β, or IL-6 plus TNF-α led to an upregulation of P-selectin, ICAM-1 and VCAM-1. Conclusion: The findings suggest that liver irradiation modulates gene expression of the main adhesion molecules in vivo and in cytokine-activated hepatocytes, with the exception of PECAM-1. This may be one reason for the lack of inflammation in the irradiated rat liver. (orig.)

In vitro and in vivo characterisation of the profibrinolytic effect of an inhibitory anti-rat TAFI nanobody.

Science.gov (United States)

Hendrickx, Maarten L V; Zatloukalova, Monika; Hassanzadeh-Ghassabeh, Gholamreza; Muyldermans, Serge; Gils, Ann; Declerck, Paul J

2014-05-05

One of the main disadvantages of current t-PA thrombolytic treatment is the increased bleeding risk. Upon activation, thrombin activatable fibrinolysis inhibitor (TAFI) is a very powerful antifibrinolytic enzyme. Therefore, co-administration of a TAFI inhibitor during thrombolysis could reduce the required t-PA dose without compromising the thrombolytic efficacy. In this study we generated and characterised a nanobody that is inhibitory towards rat TAFI and evaluated its profibrinolytic property in vitro and in vivo. Nanobody VHH-rTAFI-i81 inhibits (at a 16-fold molar ratio nanobody over TAFI) the thrombin/thrombomodulin (T/TM)-mediated activation of rat TAFI (rTAFI) by 83 ± 1.8% with an IC50 of 0.46 (molar ratio nanobody over TAFI). The affinity (KA) of VHH-rTAFI-i81 for rTAFI, as determined by surface plasmon resonance (Biacore®), is 2.5 ± 0.2 x 10(10) M(-1) and illustrates a very strong binding. In an in vitro clot lysis assay, administration of VHH-rTAFI-i81 strongly enhances the degree of lysis and reduces time to reach full lysis of t-PA-mediated clot lysis. Epitope mapping discloses that Lys392 is of primary importance for the nanobody/rTAFI interaction besides minor contributions of Tyr175 and Glu183. In vivo application of VHH-rTAFI-i81 in a tissue factor-induced mouse thromboembolism model significantly decreases fibrin deposition in the lungs in the absence of exogenous administered t-PA. Nanobody VHH-rTAFI-i81 is a very potent inhibitor of T/TM-mediated TAFI activation. Co-administration of this nanobody and t-PA enhances the fibrinolytic efficacy. In an in vivo mouse thromboembolism model, VHH-rTAFI-i81 reduces fibrin deposition in the lungs.

In vivo formation of beta-oxidized metabolites of leukotriene E4 in the rat

International Nuclear Information System (INIS)

Perrin, P.; Zirrolli, J.; Stene, D.O.; Lellouche, J.P.; Beaucourt, J.P.; Murphy, R.C.

1989-01-01

Intraperitoneal administration of [ 3 H]-leukotriene E4 in the rat resulted in the appearance of radiolabel in urine and feces. Separation of polar urinary metabolites and chromatographic comparison of synthetic metabolites indicated the in vivo formation of omega-oxidized metabolites of LTE4 with sequential beta-oxidation. Furthermore, the metabolite identified as 16-carboxy-17,18,19,20-tetranor-14,15-dihydro-N-acetyl-LTE4 substantiates the biochemical pathway of beta-oxidation in vivo involving the 2,4-dienoyl CoA reductase as an integral step. These results substantiate beta-oxidation of sulfidopeptide leukotrienes in vivo and these metabolites account for some of the major urinary metabolites of this class of lipid mediator

Dietary restriction of choline reduces hippocampal acetylcholine release in rats: in vivo microdialysis study.

Science.gov (United States)

Nakamura, A; Suzuki, Y; Umegaki, H; Ikari, H; Tajima, T; Endo, H; Iguchi, A

2001-12-01

We fed rats with a diet deficient in choline for 12 weeks and studied how dietary choline deficiency affected their behavior and their ability to release acetylcholine in discrete regions of rat brain using step-through passive avoidance task and in vivo microdialysis. In comparison with the control, rats fed the choline-deficient diet showed poorer retention of nociceptive memory in the passive avoidance task. Average choline level in cerebrospinal fluid in the choline-deficient group was significantly less (33.1%) than that of control rats. In vivo microdialysis showed no difference in the pattern of acetylcholine release enhanced by intraperitoneal administration of scopolamine hydrochloride (2 mg/kg) in the striatum between the two groups, whereas in the hippocampus, the maximum and subsequent increase of acetylcholine from the baseline by scopolamine injection was significantly lower in the choline-deficient group than in the control. From the results of our study, we speculate that long-term dietary restriction of choline can affect extra- and intracellular sources of substrates required for acetylcholine synthesis, and eventually limit the ability to release acetylcholine in the hippocampus. Reduced capacity to release acetylcholine in the hippocampus implies that the mechanism, maintaining acetylcholine synthesis on increased neuronal demand, may vary in discrete regions of the brain in response to dietary manipulation. The vulnerability of the mechanism in the hippocampus to dietary choline restriction is indicated by impaired mnemonic performance we observed.

PET imaging of neuroinflammation in a rat traumatic brain injury model with radiolabeled TSPO ligand DPA-714

Energy Technology Data Exchange (ETDEWEB)

Wang, Yu [Medical School of Southeast University, Jiangsu Key Laboratory of Molecular Imaging and Functional Imaging, Department of Radiology, Zhongda Hospital, Nanjing (China); National Institutes of Health - NIH, Laboratory of Molecular Imaging and Nanomedicine - LOMIN, National Institute of Biomedical Imaging and Bioengineering - NIBIB, Bethesda, MD (United States); Yue, Xuyi; Kiesewetter, Dale O.; Niu, Gang; Chen, Xiaoyuan [National Institutes of Health - NIH, Laboratory of Molecular Imaging and Nanomedicine - LOMIN, National Institute of Biomedical Imaging and Bioengineering - NIBIB, Bethesda, MD (United States); Teng, Gaojun [Medical School of Southeast University, Jiangsu Key Laboratory of Molecular Imaging and Functional Imaging, Department of Radiology, Zhongda Hospital, Nanjing (China)

2014-07-15

The inflammatory response in injured brain parenchyma after traumatic brain injury (TBI) is crucial in the pathological process. In order to follow microglia activation and neuroinflammation after TBI, we performed PET imaging in a rat model of TBI using {sup 18}F-labeled DPA-714, a ligand of the 18-kDa translocator protein (TSPO). TBI was induced in male SD rats by a controlled cortical impact. The success of the TBI model was confirmed by MRI. [{sup 18}F]DPA-714 was synthesized using a slightly modified TRACERLab FX-FN module and an automated procedure. In vivo PET imaging was performed at different time points after surgery using an Inveon small-animal PET scanner. The specificity of [{sup 18}F]DPA-714 was confirmed by a displacement study with an unlabeled competitive TSPO ligand, PK11195. Ex vivo autoradiography as well as immunofluorescence staining was carried out to confirm the in vivo PET results. Both in vivo T{sub 2}-weighted MR images and ex vivo TTC staining results revealed successful establishment of the TBI model. Compared with the sham-treated group, [{sup 18}F]DPA-714 uptake was significantly higher in the injured brain area on PET images. Increased lesion-to-normal ratios of [{sup 18}F]DPA-714 were observed in the brain of TBI rats on day 2 after surgery. Ratios peaked around day 6 (2.65 ± 0.36) and then decreased gradually to nearly normal levels on day 28. The displacement study using PK11195 confirmed the specific binding of [{sup 18}F]DPA-714 to TSPO. The results of ex vivo autoradiography were consistent with in vivo PET results. Immunofluorescence staining showed the time course of TSPO expression after TBI and the temporal and the spatial distribution of microglia in the damaged brain area. TSPO-targeted PET using [{sup 18}F]DPA-714 as the imaging probe can be used to dynamically monitor the inflammatory response after TBI in a noninvasive manner. This method will not only facilitate a better understanding of the inflammatory process

An in-vitro-in-vivo model for the transdermal delivery of cholecalciferol for the purposes of rodent management.

Science.gov (United States)

Davies, J; Ingham, A

2015-06-20

The natural selection of anticoagulant resistant rats has resulted in a need for an alternative to anticoagulant rodenticides which differs in both active ingredient and in the method of dosing. Cholecalciferol toxicity to rodents using the dermal route is demonstrated using a variety of penetration enhancing formulations in two in-vitro models and finally in-vivo. A 1 ml dose of 50/50 (v/v) DMSO/ethanol containing 15% (v/v) PEG 200 and 20% (w/v) cholecalciferol was judged as 'sufficiently effective' in line with the European Union's Biocidal Products Regulation (No. 528/2012) during in-vivo studies. This dose was found to cause 100% mortality in a rat population in 64.4h (± 22h). Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Biotransformation of vinclozolin in rat precision-cut liver slices: comparison with in vivo metabolic pattern.

Science.gov (United States)

Bursztyka, Julian; Debrauwer, Laurent; Perdu, Elisabeth; Jouanin, Isabelle; Jaeg, Jean-Philippe; Cravedi, Jean-Pierre

2008-06-25

Vinclozolin is a dicarboxymide fungicide that presents antiandrogenic properties through its two hydrolysis products M1 and M2, which bind to the androgen receptor. Because of the lack of data on the biotransformation of vinclozolin, its metabolism was investigated in vitro in precision-cut rat liver slices and in vivo in male rat using [ (14)C]-vinclozolin. Incubations were performed using different concentrations of substrate, and the kinetics of formation of the major metabolites were studied. Three male Wistar rats were fed by gavage with [ (14)C]-VZ. Urine was collected for 24 h and analyzed by radio-HPLC for metabolic profiling. Metabolite identification was carried out on a LCQ ion trap mass spectrometer. In rat liver slices and in vivo, the major primary metabolite has been identified as 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutyranilide (M5) and was mainly present as glucuronoconjugates. M5 is produced by dihydroxylation of the vinyl group of M2. Other metabolites have been identified as 3-(3,5-dichlorophenyl)-5-methyl-5-(1,2-dihydroxyethyl)-1,3-oxazolidine-2,4-dione (M4), a dihydroxylated metabolite of vinclozolin, which undergoes further conjugation to glucuronic acid, and 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3,4-dihydroxy-butanoic acid (M6), a dihydroxylated metabolite of M1.

Free radicals imaged in vivo in the rat by using proton-electron double-resonance imaging

International Nuclear Information System (INIS)

Lurie, D.J.; Nicholson, Ian; Foster, M.A.; Mallard, J.R.

1990-01-01

A new technique called proton-electron double-resonance imaging is described for imaging free radicals in aqueous samples. The method is a combination of proton NMR imaging with nuclear electron double resonance. The results of using this technique to image free radicals in vivo in the rat are presented. Rats were injected intravenously with a nitroxide free radical solution and a series of images was obtained from which the clearance of the free radical through the liver and kidneys could be observed. (author)

Sister chromatid exchanges in the bone marrow cells of in vivo rats induced by gamma radiation and chemical mutagens

International Nuclear Information System (INIS)

Rodriguez R, R.G.

1981-01-01

Sister chromatid exchanges (SCE) in the bone marrow of in vivo rats induced by gamma radiation doses and by the chemical mutagens, mitomycin C (MMC), cyclophosphamide (CP), and sulphonate-methylmethane (SMM), were studied. The purpose was to evaluate the sensitivity and reproducibility of a simplified SCE in vivo detecting system developed in our laboratory and to compare the results obtained with those reported elsewhere. Simplification consisted in administering the amounts of 5-bromo-2'-deoxyuridine (BrdU) necessary to observe the SCE, after first adsorbing the BrdU in activated carbon and then injecting it interperitoneally, into the rats. The results were a longer time in vivo ADN incorporation without convulsions in the rats, and a reduction in the time course as compared to other methods. We observed a basal rate of 3.6+-0.37 SCE/cell and that: 0.44 Gy of gamma radiation induced 7.7+-0.73 SCE/cell; 1.6 μg/g of MMC induced 8.1+-1.20 SCE/cell; 5 μg/g of CP induced 8.25+-1.5 SCE/cell, 40 μg/g of SMM induced 22.0+-5 SCE/cell and 380 μg/g of sulphonate-ethylmethane induced 8.6+-1.2 SCE/cell. This showed that all the agents were capable of inducing SCE in the bone marrow cells of rats in vivo under our conditions. We noted a greater induced efficiency for gamma radiation than the obtained by other investigators and a relatively similar efficiency in the case of chemical mutagens as reported in other studies. (author)

Deuterium isotope effect on metabolism of N-nitrosodimethylamine in vivo in rat

International Nuclear Information System (INIS)

Swann, P.F.; Mace, R.; Angeles, R.M.; Keefer, L.K.

1983-01-01

The maximal rates of metabolic oxidation of N-nitrosodimethylamine (NDMA) and N-nitrosodimethylamine-d6 (NDMA-d6) in vivo (VH and VD, respectively) have been measured by following 14CO2 exhalation in rats after intraperitoneal injection of the two 14C-labelled carcinogens at high doses (20 or 40 mg/kg). Complete deuteration of NDMA reduced only slightly the maximal rate of metabolism when the two substrates were administered separately (VH/VD approximately 1.2). However, much larger (approximately 4-fold) deuterium isotope effects were observed when mixtures of NDMA with NDMA-d6 were injected. These results are tentatively interpreted as evidence that C-H bond cleavage is not a rate limiting feature of overall metabolism, but that the complex between NDMA and the principal enzyme(s) metabolizing it in vivo freely equilibrates with unbound substrate. Single, large, intraperitoneal doses of NDMA and NDMA-d6 produced a similar alkylation of rat liver DNA and also of kidney DNA. However, a small oral dose (54 micrograms/kg) of NDMA-d6 produced 1/3 less alkylation of liver DNA and 3 times as much alkylation of kidney DNA as did an equimolar dose of NDMA. The reduction in alkylation of liver DNA correlates well with, and possibly explains, the decreased ability of NDMA-d6 to induce liver tumors in rats. The associated increase in the alkylation of kidney DNA suggests that this change is due to a decrease in the amount of nitrosamine removed from the portal blood on the first pass through the liver

In Vivo Quantification of Inflammation in Experimental Autoimmune Encephalomyelitis Rats Using Fluorine-19 Magnetic Resonance Imaging Reveals Immune Cell Recruitment outside the Nervous System.

Directory of Open Access Journals (Sweden)

Jia Zhong

Full Text Available Progress in identifying new therapies for multiple sclerosis (MS can be accelerated by using imaging biomarkers of disease progression or abatement in model systems. In this study, we evaluate the ability to noninvasively image and quantitate disease pathology using emerging "hot-spot" 19F MRI methods in an experimental autoimmune encephalomyelitis (EAE rat, a model of MS. Rats with clinical symptoms of EAE were compared to control rats without EAE, as well as to EAE rats that received daily prophylactic treatments with cyclophosphamide. Perfluorocarbon (PFC nanoemulsion was injected intravenously, which labels predominately monocytes and macrophages in situ. Analysis of the spin-density weighted 19F MRI data enabled quantification of the apparent macrophage burden in the central nervous system and other tissues. The in vivo MRI results were confirmed by extremely high-resolution 19F/1H magnetic resonance microscopy in excised tissue samples and histopathologic analyses. Additionally, 19F nuclear magnetic resonance spectroscopy of intact tissue samples was used to assay the PFC biodistribution in EAE and control rats. In vivo hot-spot 19F signals were detected predominantly in the EAE spinal cord, consistent with the presence of inflammatory infiltrates. Surprising, prominent 19F hot-spots were observed in bone-marrow cavities adjacent to spinal cord lesions; these were not observed in control animals. Quantitative evaluation of cohorts receiving cyclophosphamide treatment displayed significant reduction in 19F signal within the spinal cord and bone marrow of EAE rats. Overall, 19F MRI can be used to quantitatively monitored EAE disease burden, discover unexpected sites of inflammatory activity, and may serve as a sensitive biomarker for the discovery and preclinical assessment of novel MS therapeutic interventions.

In Vivo Real-Time Imaging of Exogenous HGF-Triggered Cell Migration in Rat Intact Soleus Muscles

International Nuclear Information System (INIS)

Ishido, Minenori; Kasuga, Norikatsu

2012-01-01

The transplantation of myogenic cells is a potentially effective therapy for muscular dystrophy. However, this therapy has achieved little success because the diffusion of transplanted myogenic cells is limited. Hepatocyte growth factor (HGF) is one of the primary triggers to induce myogenic cell migration in vitro. However, to our knowledge, whether exogenous HGF can trigger the migration of myogenic cells (i.e. satellite cells) in intact skeletal muscles in vivo has not been reported. We previously reported a novel in vivo real-time imaging method in rat skeletal muscles. Therefore, the present study examined the relationship between exogenous HGF treatment and cell migration in rat intact soleus muscles using this imaging method. As a result, it was indicated that the cell migration velocity was enhanced in response to increasing exogenous HGF concentration in skeletal muscles. Furthermore, the expression of MyoD was induced in satellite cells in response to HGF treatment. We first demonstrated in vivo real-time imaging of cell migration triggered by exogenous HGF in intact soleus muscles. The experimental method used in the present study will be a useful tool to understand further the regulatory mechanism of HGF-induced satellite cell migration in skeletal muscles in vivo

In vivo turnover rates of rat peripheral blood and spleen LGL

International Nuclear Information System (INIS)

Reichardt, D.; Mason, L.H.; Rolstad, B.; Reynolds, C.W.

1986-01-01

Recently much data has accumulated on the morphology and function of LGL. However, there is still little definitive information regarding the lineage and in vivo dynamics of these cells. The present experiments were designed to study one aspect of LGL biology, their in vivo turnover rate. F344 rats were injected 2x daily with 100 μCi 3 HTdR for 1-7 days, their bone marrow (BM) spleens (SPL) and peripheral blood (PB) collected, and LGL and T cells isolated on Percoll gradients. These cell preparations were counted for total radioactivity by scintillation counting and % of labeled cells determined by autoradiography. The results demonstrated the highest 3 HTdR counts were from Percoll fractions 1 and 2 (LGL) with almost no CPM in those fractions containing T cells. The autoradiography data demonstrated that PB and SPL LGL, unlike T cells, were derived from a rapidly dividing precursor population since 30-40% of the LGL were labeled by a 5 day 3 HTdR pulse. In contrast 3 HTdR. Calculations of the approximate steady state turnover rates in these normal rats were BM = 5 days, LGL = 7 days and T cells = >30 days. These results clearly demonstrate that unlike mature T cells, PB and SPL LGL are derived from a rapidly dividing precursor population. More definitive experiments to calculate the half-life of these cells are currently underway

Physical limits to autofluorescence signals in vivo recordings in the rat olfactory bulb: a Monte Carlo study

Science.gov (United States)

L'Heureux, B.; Gurden, H.; Pinot, L.; Mastrippolito, R.; Lefebvre, F.; Lanièce, P.; Pain, F.

2007-07-01

Understanding the cellular mechanisms of energy supply to neurons following physiological activation is still challenging and has strong implications to the interpretation of clinical functional images based on metabolic signals such as Blood Oxygen Level Dependent Magnetic Resonance Imaging or 18F-Fluorodexoy-Glucose Positron Emission Tomography. Intrinsic Optical Signal Imaging provides with high spatio temporal resolution in vivo imaging in the anaesthetized rat. In that context, intrinsic signals are mainly related to changes in the optical absorption of haemoglobin depending on its oxygenation state. This technique has been validated for imaging of the rat olfactory bulb, providing with maps of the actived olfactory glomeruli, the functional modules involved in the first step of olfactory coding. A complementary approach would be autofluorescence imaging relying on the fluorescence properties of endogenous Flavin Adenine Dinucleotide (FAD) or Nicotinamide Adenine Dinucleotide (NADH) both involved in intracellular metabolic pathways. The purpose of the present study was to investigate the feasibility of in vivo autofluorescence imaging in the rat olfactory bulb. We performed standard Monte Carlo simulations of photons scattering and absorption at the excitation and emission wavelengths of FAD and NADH fluorescence. Characterization of the fluorescence distribution in the glomerulus, effect of hemoglobin absorption at the excitation and absorption wavelengths as well as the effect of the blurring due to photon scattering and the depth of focus of the optical apparatus have been studied. Finally, optimal experimental parameters are proposed to achieve in vivo validation of the technique in the rat olfactory bulb.

Combined effects of porous hydroxyapatite and demineralized bone matrix on bone induction: in vitro and in vivo study using a nude rat model

Energy Technology Data Exchange (ETDEWEB)

Lee, Jae Hyup; Lee, Kyung-Mee; Baek, Hae-Ri; Jang, Soo-Jeong; Lee, Ji-Ho [Department of Orthopedic Surgery, Seoul National University School of Medicine, SMG-SNU Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Ryu, Hyun-Seung, E-mail: spinelee@snu.ac.kr [Research and Development Center, CGBio Inc., Seong-Nam 462-120 (Korea, Republic of)

2011-02-15

Hydroxyapatite (HA) is an osteoconductive material used as a bone graft extender and demineralized bone matrix (DBM) has been used as a source of osteoinductive factors. A combination of DBM and HA is expected to create a composite with both osteoconductive and osteoinductive properties. This study examined the effect of a combination of DBM and HA on osteogenesis both in vitro and in vivo using an athymic nude rat abdominal muscle pouch model, and evaluated the possibility of HA as a carrier of DBM. Alkaline phosphatase (ALP) staining, ALP assay and measurements of the mRNA expression of ALP and Runx2 by RT-PCR were performed by transplanting human mesenchymal stem cells onto a plate. Five athymic nude rats each were assigned to one of two experimental groups (DBM/HA putty and only HA, i.e. 15 pouches per group). The muscle pouches were filled with DBM/HA putty or only HA. Radiographs were obtained at weeks 4 and 8, postoperatively. The animals were sacrificed at week 8 postoperatively and high resolution microCT was used to confirm the newly formed mineralized tissue. Each pouch was fixed, embedded, sectioned and processed for hematoxylin and eosin staining. The ALP value of the DBM/HA putty was higher than those of HA and control (p < 0.05, each). The expression of ALP mRNA appeared higher on the DBM/HA putty than on HA and control. MicroCT and histology examinations of the DBM/HA putty demonstrated the presence of newly generated mineralized tissues but there was no mineralized tissue in the HA cases. In conclusion, the DBM/HA putty indicated osteoblastic differentiation in vitro and showed ectopic mineralized tissue formation in the rat abdominal pouch model. These findings indicate that the DBM/HA putty can retain its oteoinductivity and HA can be used as a carrier of DBM.

Combined effects of porous hydroxyapatite and demineralized bone matrix on bone induction: in vitro and in vivo study using a nude rat model

International Nuclear Information System (INIS)

Lee, Jae Hyup; Lee, Kyung-Mee; Baek, Hae-Ri; Jang, Soo-Jeong; Lee, Ji-Ho; Ryu, Hyun-Seung

2011-01-01

Hydroxyapatite (HA) is an osteoconductive material used as a bone graft extender and demineralized bone matrix (DBM) has been used as a source of osteoinductive factors. A combination of DBM and HA is expected to create a composite with both osteoconductive and osteoinductive properties. This study examined the effect of a combination of DBM and HA on osteogenesis both in vitro and in vivo using an athymic nude rat abdominal muscle pouch model, and evaluated the possibility of HA as a carrier of DBM. Alkaline phosphatase (ALP) staining, ALP assay and measurements of the mRNA expression of ALP and Runx2 by RT-PCR were performed by transplanting human mesenchymal stem cells onto a plate. Five athymic nude rats each were assigned to one of two experimental groups (DBM/HA putty and only HA, i.e. 15 pouches per group). The muscle pouches were filled with DBM/HA putty or only HA. Radiographs were obtained at weeks 4 and 8, postoperatively. The animals were sacrificed at week 8 postoperatively and high resolution microCT was used to confirm the newly formed mineralized tissue. Each pouch was fixed, embedded, sectioned and processed for hematoxylin and eosin staining. The ALP value of the DBM/HA putty was higher than those of HA and control (p < 0.05, each). The expression of ALP mRNA appeared higher on the DBM/HA putty than on HA and control. MicroCT and histology examinations of the DBM/HA putty demonstrated the presence of newly generated mineralized tissues but there was no mineralized tissue in the HA cases. In conclusion, the DBM/HA putty indicated osteoblastic differentiation in vitro and showed ectopic mineralized tissue formation in the rat abdominal pouch model. These findings indicate that the DBM/HA putty can retain its oteoinductivity and HA can be used as a carrier of DBM.

Metabolic-dopaminergic mapping of the 6-hydroxydopamine rat model for Parkinson's disease

International Nuclear Information System (INIS)

Casteels, Cindy; Lauwers, Erwin; Baekelandt, Veerle; Bormans, Guy; Laere, Koen van

2008-01-01

The unilateral 6-hydroxydopamine (6-OHDA) lesion rat model is a well-known acute model for Parkinson's disease (PD). Its validity has been supported by invasive histology, behavioral studies and electrophysiology. Here, we have characterized this model in vivo by multitracer imaging [glucose metabolism and dopamine transporter (DAT)] in relation to behavioral and histological parameters. Eighteen female adult Wistar rats (eight 6-OHDA-lesioned, ten controls) were investigated using multitracer [ 18 F]-fluoro-2-deoxy-D-glucose (FDG) and [ 18 F]-FECT 2'-[ 18 F]-fluoroethyl-(1R-2-exo-3-exe)-8-methyl-3-(4-chlorophenyl)- 8-azabicyclo (3.2.1)-octane-2-carboxylate small animal positron emission tomography (PET). Relative glucose metabolism and parametric DAT binding images were anatomically standardized to Paxinos space and analyzed on a voxel-basis using SPM2, supplemented by a template-based predefined volumes-of-interest approach. Behavior was characterized by the limb-use asymmetry test; dopaminergic innervation was validated by in vitro tyrosine hydroxylase staining. In the 6-OHDA model, significant glucose hypometabolism is present in the ipsilateral sensory-motor cortex (-6.3%; p = 4 x 10 -6 ). DAT binding was severely decreased in the ipsilateral caudate-putamen, nucleus accumbens and substantia nigra (all p -9 ), as confirmed by the behavioral and histological outcomes. Correlation analysis revealed a positive relationship between the degree of DAT impairment and the change in glucose metabolism in the ipsilateral hippocampus (p = 3 x 10 -5 ), while cerebellar glucose metabolism was inversely correlated to the level of DAT impairment (p -4 ). In vivo cerebral mapping of 6-OHDA-lesioned rats using [ 18 F ]-FDG and [ 18 F ]-FECT small animal PET shows molecular-functional correspondence to the cortico-subcortical network impairments observed in PD patients. This provides a further molecular validation supporting the validity of the 6-OHDA lesion model to mimic

Induction of 6-thioguanine-resistant lymphocytes in Fischer 344 rats following in vivo exposure to N-ethyl-N-nitrosourea and cyclophosphamide

International Nuclear Information System (INIS)

Aidoo, A.; Lyn-Cook, L.E.; Mittelstaedt, R.A.; Heflich, R.H.; Casciano, D.A.

1991-01-01

The authors have developed a limiting dilution clonal assay for determining the frequency of 6-thioguanine-resistant (TG r ) lymphocytes produced in rats by in vivo exposure to genotoxic agents. Lymphocyte cloning efficiencies (CEs) were highest in plates containing both irradiated TK6 cells and irradiated autologous feeder cells. To measure the effects of chemical mutagens on the frequency of TG r lymphocytes, rats were given a single i.p. injection of N-ethyl-N-nitrosourea (ENU), a direct-acting alkylating agent, cyclophosphamide (CP), an indirect acting alkylating agent. Lymphocytes were isolated, primed, and cloned at 4 weeks after CP treatment and at 1,2,4 and 6 weeks after ENU treatment. CE in these cultures ranged from 12% to 27%. Cultures were also established for measuring CE in the presence of 6-thioguanine (TG). The dose-dependent responses obtained with both ENU and CP treatments suggest that rat lymphocytes are sensitive to direct- and indirect-acting alkylating agents administered in vivo and that the rat lymphocyte assay is a useful complement to the in vivo/in vitro mouse assay for determining the mutagenicity of environmental toxicants

Translational step inhibited in vivo by aflatoxin B1 in rat-liver polysomes

International Nuclear Information System (INIS)

Sarasin, A.; Moule, Y.

1975-01-01

Aflatoxin B 1 strongly inhibits protein synthesis in rat liver cells. This paper confirms the foregoing results and represents an attempt to localize the translational step inhibited in vivo by aflatoxin B 1 . We used the simulation study developed by Li, Kisilevsky, Wasan and Hammond, 1972 (Biochim. Biophys. Acta, 272, 451-462) to determine precisely the site inhibited in vivo after drug intoxication. This analysis is based on two parameters: the kinetics of polysome labeling to follow the nascent peptide synthesis, and the kinetics of supernatant labeling to follow the completed protein synthesis. Up to 5 h after dosing, aflatoxin specifically inhibits the elongation and/or termination steps during protein synthesis; after longer periods of time inhibition occurs essentially at the initiation step. When the intracellular concentration of aflatoxin is too high, particularly 2 h after dosing, each step of protein synthesis is blocked. Polypeptide synthesis by the postmitochondrial supernatants isolated from aflatoxin-treated animals is impaired in the same proportion as protein synthesis in vivo. The damage caused by aflatoxin is mostly observed on microsomes. However, purified polysomes isolated from aflatoxin-treated rats synthesize proteins in vitro to the same extent as those from controls. These results suggest that aflatoxin metabolite(s) are bound to polysomes with noncovalent bonds. These active metabolites are probably lost during polysome isolation procedures. Finally, relationships between protein metabolism and aflatoxin carcinogenesis are discussed. (orig./BSC) [de

Cyclosporine, a P-glycoprotein modulator, increases [18F]MPPF uptake in rat brain and peripheral tissues: microPET and ex vivo studies

International Nuclear Information System (INIS)

Lacan, Goran; Way, Baldwin M.; Plenevaux, Alain; Defraiteur, Caroline; Lemaire, Christian; Aerts, Joel; Luxen, Andre; Rubins, Daniel J.; Cherry, Simon R.; Melega, William P.

2008-01-01

Pretreatment with cyclosporine, a P-glycoprotein (P-gp) modulator increases brain uptake of 4-(2'-methoxyphenyl)-1-[2'-(N-2''-pyridinyl)-p-[ 18 F] fluorobenzamido] ethylpiper azine ([ 18 F]MPPF) for binding to hydroxytryptamine 1A (5-HT 1A ) receptors. Those increases were quantified in rat brain with in vivo microPET and ex vivo tissue studies. Each Sprague-Dawley rat (n=4) received a baseline [ 18 F]MPPF microPET scan followed by second scan 2-3 weeks later that included cyclosporine pretreatment (50 mg/kg, i.p.). Maximum a posteriori reconstructed images and volumetric ROIs were used to generate dynamic radioactivity concentration measurements for hippocampus, striatum, and cerebellum, with simplified reference tissue method (SRTM) analysis. Western blots were used to semiquantify P-gp regional distribution in brain. MicroPET studies showed that hippocampus uptake of [ 18 F]MPPF was increased after cyclosporine; ex vivo studies showed similar increases in hippocampus and frontal cortex at 30 min, and for heart and kidney at 2.5 and 5 min, without concomitant increases in [ 18 F]MPPF plasma concentration. P-gp content in cerebellum was twofold higher than in hippocampus or frontal cortex. These studies confirm and extend prior ex vivo results (J. Passchier, et al., Eur J Pharmacol, 2000) that showed [ 18 F]MPPF as a substrate for P-gp. Our microPET results showed that P-gp modulation of [ 18 F]MPPF binding to 5-HT 1A receptors can be imaged in rat hippocampus. The heterogeneous brain distribution of P-gp appeared to invalidate the use of cerebellum as a nonspecific reference region for SRTM modeling. Regional quantitation of P-gp may be necessary for accurate PET assessment of 5-HT 1A receptor density when based on tracer uptake sensitive to P-gp modulation. (orig.)

Improving in vitro to in vivo extrapolation by incorporating toxicokinetic measurements: A case study of lindane-induced neurotoxicity

Energy Technology Data Exchange (ETDEWEB)

Croom, Edward L.; Shafer, Timothy J.; Evans, Marina V.; Mundy, William R.; Eklund, Chris R.; Johnstone, Andrew F.M.; Mack, Cina M.; Pegram, Rex A., E-mail: pegram.rex@epa.gov

2015-02-15

Approaches for extrapolating in vitro toxicity testing results for prediction of human in vivo outcomes are needed. The purpose of this case study was to employ in vitro toxicokinetics and PBPK modeling to perform in vitro to in vivo extrapolation (IVIVE) of lindane neurotoxicity. Lindane cell and media concentrations in vitro, together with in vitro concentration-response data for lindane effects on neuronal network firing rates, were compared to in vivo data and model simulations as an exercise in extrapolation for chemical-induced neurotoxicity in rodents and humans. Time- and concentration-dependent lindane dosimetry was determined in primary cultures of rat cortical neurons in vitro using “faux” (without electrodes) microelectrode arrays (MEAs). In vivo data were derived from literature values, and physiologically based pharmacokinetic (PBPK) modeling was used to extrapolate from rat to human. The previously determined EC{sub 50} for increased firing rates in primary cultures of cortical neurons was 0.6 μg/ml. Media and cell lindane concentrations at the EC{sub 50} were 0.4 μg/ml and 7.1 μg/ml, respectively, and cellular lindane accumulation was time- and concentration-dependent. Rat blood and brain lindane levels during seizures were 1.7–1.9 μg/ml and 5–11 μg/ml, respectively. Brain lindane levels associated with seizures in rats and those predicted for humans (average = 7 μg/ml) by PBPK modeling were very similar to in vitro concentrations detected in cortical cells at the EC{sub 50} dose. PBPK model predictions matched literature data and timing. These findings indicate that in vitro MEA results are predictive of in vivo responses to lindane and demonstrate a successful modeling approach for IVIVE of rat and human neurotoxicity. - Highlights: • In vitro to in vivo extrapolation for lindane neurotoxicity was performed. • Dosimetry of lindane in a micro-electrode array (MEA) test system was assessed. • Cell concentrations at the MEA EC

Pharmacokinetic-pharmacodynamic modeling of diclofenac in normal and Freund's complete adjuvant-induced arthritic rats

Science.gov (United States)

Zhang, Jing; Li, Pei; Guo, Hai-fang; Liu, Li; Liu, Xiao-dong

2012-01-01

Aim: To characterize pharmacokinetic-pharmacodynamic modeling of diclofenac in Freund's complete adjuvant (FCA)-induced arthritic rats using prostaglandin E2 (PGE2) as a biomarker. Methods: The pharmacokinetics of diclofenac was investigated using 20-day-old arthritic rats. PGE2 level in the rats was measured using an enzyme immunoassay. A pharmacokinetic-pharmacodynamic (PK-PD) model was developed to illustrate the relationship between the plasma concentration of diclofenac and the inhibition of PGE2 production. The inhibition of diclofenac on lipopolysaccharide (LPS)-induced PGE2 production in blood cells was investigated in vitro. Results: Similar pharmacokinetic behavior of diclofenac was found both in normal and FCA-induced arthritic rats. Diclofenac significantly decreased the plasma levels of PGE2 in both normal and arthritic rats. The inhibitory effect on PGE2 levels in the plasma was in proportion to the plasma concentration of diclofenac. No delay in the onset of inhibition was observed, suggesting that the effect compartment was located in the central compartment. An inhibitory effect sigmoid Imax model was selected to characterize the relationship between the plasma concentration of diclofenac and the inhibition of PGE2 production in vivo. The Imax model was also used to illustrate the inhibition of diclofenac on LPS-induced PGE2 production in blood cells in vitro. Conclusion: Arthritis induced by FCA does not alter the pharmacokinetic behaviors of diclofenac in rats, but the pharmacodynamics of diclofenac is slightly affected. A PK-PD model characterizing an inhibitory effect sigmoid Imax can be used to fit the relationship between the plasma PGE2 and diclofenac levels in both normal rats and FCA-induced arthritic rats. PMID:22842736

In vivo detection of dynamics of elements in a living rat using multitracer technique

International Nuclear Information System (INIS)

Matsumoto, Ken-ichiro; Ui, Iori; Endo, Kazutoyo; Hirunuma, Rieko; Enomoto, Shuichi

2002-01-01

In vivo detection technique for radioactivity of the nuclide in the multitracer intravenously administered to a living rat was proposed using a special setting of lead slit and high-purity Ge semiconducting detector. In vivo time courses of the relative distribution of 7 Be, 4 8 V, 54 Mn, 58 Co, 65 Zn, 74 As, 75 Se, 83 Rb, 85 Sr, and 88 Y in upper abdomen and head of six week old male Wistar rats were analyzed. The dynamics of the elements were estimated using the relative distribution of 74 As as base line of blood concentration, since exogenous arsenic tracer is mainly taken into red blood cell. In the head, elements distributed mainly in bones or muscles except for Co and Se, while these elements in blood. In the upper abdomen, Mn, Co, Zn, Se, Rb, V, and Y are distributed in to the liver, which is a main organ for accumulating metals. It is the first report that dynamics of biotrace elements within an hour after administration was non-invasively obtained in living animal. (author)

Hindlimb unloading in rat decreases preosteoblast proliferation assessed in vivo with BrdU incorporation.

Science.gov (United States)

Barou, O; Palle, S; Vico, L; Alexandre, C; Lafage-Proust, M H

1998-01-01

Immobilization affects bone formation. However, the mechanisms regulating the decrease in osteoblast recruitment remain unclear. The aim of our study was to determine in vivo osteoblastic proliferation after short-term immobilization among the different bone compartments. Twelve Wistar 5-wk-old rats were assigned to two groups: six tail-suspended animals for 6 days and their six age-related controls. Osmotic minipumps, each containing 40 mg of bromodeoxyuridine (BrdU), were implanted intraperitoneally at day 4 until euthanasia. Histomorphometric measurements found a significantly lower bone volume in primary (ISP, -22%) and secondary spongiosa (IISP, -37%) in unloaded rats compared with their age-related controls. BrdU immunohistochemistry showed that the proliferation capacity of osteogenic precursors in ISP (-29%) and preosteoblasts in IISP (-80%) and in periosteum as well as bone marrow cells (-40%) was lowered by unloading. We demonstrated in vivo for the first time that 6-day tail suspension induced a significant decrease in proliferation of periosteal and trabecular preosteoblasts in ISP and IISP as well as in bone marrow cells.

Role of xanthine oxidoreductase in the anti-thrombotic effects of nitrite in rats in vivo.

Science.gov (United States)

Kramkowski, K; Leszczynska, A; Przyborowski, K; Kaminski, T; Rykaczewska, U; Sitek, B; Zakrzewska, A; Proniewski, B; Smolenski, R T; Chabielska, E; Buczko, W; Chlopicki, S

2016-01-01

The mechanisms underlying nitrite-induced effects on thrombosis and hemostasis in vivo are not clear. The goal of the work described here was to investigate the role of xanthine oxidoreductase (XOR) in the anti-platelet and anti-thrombotic activities of nitrite in rats in vivo. Arterial thrombosis was induced electrically in rats with renovascular hypertension by partial ligation of the left renal artery. Sodium nitrite (NaNO2, 0.17 mmol/kg twice daily for 3 days, p.o) was administered with or without one of the XOR-inhibitors: allopurinol (ALLO) and febuxostat (FEB) (100 and 5 mg/kg, p.o., for 3 days). Nitrite treatment (0.17 mmol/kg), which was associated with a significant increase in NOHb, nitrite/nitrate plasma concentration, resulted in a substantial decrease in thrombus weight (TW) (0.48 ± 0.03 mg vs. vehicle [VEH] 0.88 ± 0.08 mg, p < 0.001) without a significant hypotensive effect. The anti-thrombotic effect of nitrite was partially reversed by FEB (TW = 0.63 ± 0.06 mg, p < 0.05 vs. nitrites), but not by ALLO (TW = 0.43 ± 0.02 mg). In turn, profound anti-platelet effect of nitrite measured ex vivo using collagen-induced whole-blood platelet aggregation (70.5 ± 7.1% vs. VEH 100 ± 4.5%, p < 0.05) and dynamic thromboxaneB2 generation was fully reversed by both XOR-inhibitors. In addition, nitrite decreased plasminogen activator inhibitor-1 concentration (0.47 ± 0.13 ng/ml vs. VEH 0.62 ± 0.04 ng/ml, p < 0.05) and FEB/ALLO reversed this effect. In vitro the anti-platelet effect of nitrite (1 mM) was reversed by FEB (0.1 mM) under hypoxia (0.5%O2) and normoxia (20%O2). Nitrite treatment had no effect on coagulation parameters. In conclusion, the nitrite-induced anti-platelet effect in rats in vivo is mediated by XOR, but XOR does not fully account for the anti-thrombotic effects of nitrite.

In vivo deep brain imaging of rats using oral-cavity illuminated photoacoustic computed tomography

Science.gov (United States)

Lin, Li; Xia, Jun; Wong, Terence T. W.; Zhang, Ruiying; Wang, Lihong V.

2015-03-01

We demonstrate, by means of internal light delivery, photoacoustic imaging of the deep brain of rats in vivo. With fiber illumination via the oral cavity, we delivered light directly into the bottom of the brain, much more than can be delivered by external illumination. The study was performed using a photoacoustic computed tomography (PACT) system equipped with a 512-element full-ring transducer array, providing a full two-dimensional view aperture. Using internal illumination, the PACT system provided clear cross sectional photoacoustic images from the palate to the middle brain of live rats, revealing deep brain structures such as the hypothalamus, brain stem, and cerebral medulla.

In vivo and in vitro conversion of 7-dehydrocholesterol into vitamin D3 in rat skin by ultraviolet ray's irradiation

International Nuclear Information System (INIS)

Okano, Toshio; Yasumura, Mitsue; Mizuno, Kumiko; Kobayashi, Tadashi

1978-01-01

The photochemical conversion of 7-dehydrocholesterol (7-DHC) into vitamin D 3 in rat skin was experimentally studied. The skin stripped off from a sacrificed normal rat was irradiated with an ultraviolet light for a constant period in the first in vitro experiment. The normal rat irradiated under the same conditions mentioned above was sacrificed and then the skin was stripped off in the second in vivo experiment. Lipids were individually extracted with chloroformmethanol (1:1) from the skin obtained in the two experiments and the solvent was evaporated. The resulting residue was saponified and the unsaponified matter extracted with benzene was purified by application to hydroxyalkoxypropyl (HAP) Sephadex column chromatography. The resulting purified vitamin D 3 fraction was applied to high performance liquid chromatography (HPLC) in order to estimate vitamin D 3 . No peak, aside from that of alphanaphthol as an initial standard, was observed in the HPLC chromatogram on the skin obtained from the non-irradiated rat, whereas the peak corresponding to vitamin D 3 was observed in each HPLC chromatogram on both the irradiated skin (in vitro experiment) and the skin obtained from the irradiated rat (in vivo experiment). The result shows that 7-DHC in rat skin was photochemically converted into vitamin D 3 . (Iwakiri, K.)

Poly(anhydride-co-imides): in vivo biocompatibility in a rat model.

Science.gov (United States)

Ibim, S M; Uhrich, K E; Bronson, R; El-Amin, S F; Langer, R S; Laurencin, C T

1998-05-01

The degradation and tissue compatibility characteristics of a novel class of biodegradable poly(anhydride-co-imide) polymers: poly[trimellitylimidoglycine-co-1,6-bis(carboxyphenoxy)hexan e] (TMA-gly: CPH) (in 10:90; 30:70 and 50: 50 molar ratios) and poly[pyromellitylimidoalanine-co-1,6-bis(carboxyphenoxy)hexa ne] (PMA-ala:CPH) (in 10:90 and 30:70 molar ratios) were investigated and compared with control poly(lactic acid/glycolic acid) (PLAGA in 50:50 molar ratio) matrices, a well-characterized biocompatible polymer, in rat subcutaneous tissues for 60 days. Polymers were compression-molded into circular discs of 14 mm x 1 mm in diameter. On post-operative days 7, 14, 28 and 60, histological tissue samples were removed, prepared by fixation and staining, and analyzed by light microscopy. PLAGA matrices produced mild inflammatory reactions and were completely degraded at the end of 60 days, leaving implant tissues that were similar to surgical wounds without implants. TMA-gly:CPH (10:90 and 30:70) matrices produced mild inflammatory reactions by the end of 60 days, similar to those seen with PLAGA. TMA-gly: CPH (50: 50) produced moderate inflammatory reactions characterized by macrophages and edema. PMA-ala:CPH matrices elicited minimal inflammatory reactions that were characterized by fibrous encapsulation by the end of 60 days. In vivo degradation rates of poly(anhydride-co-imides) were similar to PLAGA. Both PMA-ala:CPH and TMA-gly: CPH matrices maintained their shapes and degraded at a constant rate over the period of two months. These polymers, possessing good mechanical properties and tissue compatibility, may be useful in weight-bearing applications in bone.

Protein metabolism in the rat cerebral cortex in vivo and in vitro as affected by the acquisition enhancing drug piracetam

NARCIS (Netherlands)

Nickolson, V.J.; Wolthuis, O.L.

1976-01-01

The effect of Piracetam on rat cerebral protein metabolism in vivo and in vitro was studied. It was found that the drug stimulates the uptake of labelled leucine by cerebral cortex slices, has no effect on the incorporation of leucine into cerebral protein, neither in slices nor in vivo, but

Target-selected mutagenesis of the rat

NARCIS (Netherlands)

Smits, B.M.; Mudde, J.B.; Plasterk, R.; Cuppen, E.

2004-01-01

The rat is one of the most extensively studied model organisms, and with its genome being sequenced, tools to manipulate gene function in vivo have become increasingly important. We here report proof of principle for target-selected mutagenesis as a reverse genetic or knockout approach for the rat.

Effect of IgG subclasses on in vivo bioavailability and metabolic fate of immune-complexed insulin in Lewis rats

International Nuclear Information System (INIS)

Arquilla, E.R.; Stenger, D.; McDougall, B.; Ulich, T.R.

1987-01-01

The bioavailability, distribution, and metabolic fate of 125 I-labeled insulin complexed to antibodies in guinea pig antiserum, purified guinea pig IgG1, IgG2, a mixture of IgG1 and IgG2, and homologous Lou/m rat antiserum were studied in inbred Lewis rats. 125 I-insulin complexed to purified guinea pig IgG2 antibodies was rapidly cleared from the blood and sequestered in increasing amounts with time in the liver. Large amounts of the 125 I-insulin complexed to guinea pig IgG1 antibodies remained in the blood for at least 30 min. The bioavailability of 125 I-insulin bound to IgG1 and IgG2 antibodies was inhibited for at least 30 min because significantly less was available for rapid binding to insulin receptors on hepatocytes and renal tubular cells and its subsequent rapid degradation. The bioavailability of 125 I-insulin was further decreased when bound to antibodies in native guinea pig antiserum or a mixture of IgG1 and IgG2 antibodies compared with the 125 I-insulin complexed to either purified IgG1 or IgG2 antibodies alone. The 125 I-insulin bound to antibodies in native guinea pig antiserum or a mixture of IgG1 and IgG2 antibodies was distributed in vivo in a manner reflecting the relative concentrations of the IgG1 and IgG2 antibodies present. The bioavailability, distribution, and metabolic fate of 125 I-insulin in immune complexes prepared with homologous Lou/m rat insulin antiserum was qualitatively similar to that observed with immune complexes prepared with guinea pig insulin antiserum. It appears that the Lewis rat can be used as an in vivo model to study the bioavailability,distribution,and metabolic fate of insulin bound to xenogenic or homologous insulin antibodies

Experimental chronic kidney disease attenuates ischemia-reperfusion injury in an ex vivo rat lung model.

Directory of Open Access Journals (Sweden)

Chung-Kan Peng

Full Text Available Lung ischemia reperfusion injury (LIRI is one of important complications following lung transplant and cardiopulmonary bypass. Although patients on hemodialysis are still excluded as lung transplant donors because of the possible effects of renal failure on the lungs, increased organ demand has led us to evaluate the influence of chronic kidney disease (CKD on LIRI. A CKD model was induced by feeding Sprague-Dawley rats an adenine-rich (0.75% diet for 2, 4 and 6 weeks, and an isolated rat lung in situ model was used to evaluate ischemia reperfusion (IR-induced acute lung injury. The clinicopathological parameters of LIRI, including pulmonary edema, lipid peroxidation, histopathological changes, immunohistochemistry changes, chemokine CXCL1, inducible nitric oxide synthase (iNOS, proinflammatory and anti-inflammatory cytokines, heat shock protein expression, and nuclear factor-κB (NF-κB activation were determined. Our results indicated that adenine-fed rats developed CKD as characterized by increased blood urea nitrogen and creatinine levels and the deposition of crystals in the renal tubules and interstitium. IR induced a significant increase in the pulmonary arterial pressure, lung edema, lung injury scores, the expression of CXCL1 mRNA, iNOS level, and protein concentration of the bronchial alveolar lavage fluid (BALF. The tumor necrosis factor-α levels in the BALF and perfusate; the interleukin-10 level in the perfusate; and the malondialdehyde levels in the lung tissue and perfusate were also significantly increased by LIRI. Counterintuitively, adenine-induced CKD significantly attenuated the severity of lung injury induced by IR. CKD rats exhibited increased heat shock protein 70 expression and decreased activation of NF-κB signaling. In conclusion, adenine-induced CKD attenuated LIRI by inhibiting the NF-κB pathway.

Intracochlear electrical stimulation suppresses apoptotic signaling in rat spiral ganglion neurons after deafening in vivo.

Science.gov (United States)

Kopelovich, Jonathan C; Cagaanan, Alain P; Miller, Charles A; Abbas, Paul J; Green, Steven H

2013-11-01

To establish the intracellular consequences of electrical stimulation to spiral ganglion neurons after deafferentation. Here we use a rat model to determine the effect of both low and high pulse rate acute electrical stimulation on activation of the proapoptotic transcription factor Jun in deafferented spiral ganglion neurons in vivo. Experimental animal study. Hearing research laboratories of the University of Iowa Departments of Biology and Otolaryngology. A single electrode was implanted through the round window of kanamycin-deafened rats at either postnatal day 32 (P32, n = 24) or P60 (n = 22) for 4 hours of stimulation (monopolar, biphasic pulses, amplitude twice electrically evoked auditory brainstem response [eABR] threshold) at either 100 or 5000 Hz. Jun phosphorylation was assayed by immunofluorescence to quantitatively assess the effect of electrical stimulation on proapoptotic signaling. Jun phosphorylation was reliably suppressed by 100 Hz stimuli in deafened cochleae of P32 but not P60 rats. This effect was not significant in the basal cochlear turns. Stimulation frequency may be consequential: 100 Hz was significantly more effective than was 5 kHz stimulation in suppressing phospho-Jun. Suppression of Jun phosphorylation occurs in deafferented spiral ganglion neurons after only 4 hours of electrical stimulation. This finding is consistent with the hypothesis that electrical stimulation can decrease spiral ganglion neuron death after deafferentation.

Sida rhomboidea.Roxb aqueous extract down-regulates in vivo expression of vascular cell adhesion molecules in atherogenic rats and inhibits in vitro macrophage differentiation and foam cell formation.

Science.gov (United States)

Thounaojam, Menaka C; Jadeja, Ravirajsinh N; Salunke, Sunita P; Devkar, Ranjitsinh V; Ramachandran, A V

2012-10-01

The present study evaluates efficacy of Sida rhomboidea.Roxb (SR) leaves extract in ameliorating experimental atherosclerosis using in vitro and in vivo experimental models. Atherogenic (ATH) diet fed rats recorded significant increment in the serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very LDL (VLDL), autoantibody against oxidized LDL (Ox-LDL), markers of LDL oxidation and decrement in high-density lipoprotein (HDL) along with increment in aortic TC and TG. The ex vivo LDL oxidation assay revealed an increased susceptibility of LDL isolated from ATH rats to undergo copper mediated oxidation. These set of changes were minimized by simultaneous co-supplementation of SR extract to ATH diet fed rats. Histopathology of aorta and immunolocalization studies recorded pronounced atheromatous plaque formation, vascular calcification, significant elastin derangements and higher expression of macrophage surface marker (F4/80), vascular cell adhesion molecule-1 (VCAM-1) and p-selectin in ATH rats. Whereas, ATH+SR rats depicted minimal evidence of atheromatous plaque formation, calcium deposition, distortion/defragmentation of elastin and accumulation of macrophages along with lowered expression of VCAM-1 and P-selectin compared to ATH rats. Further, monocyte to macrophage differentiation and in vitro foam cell formation were significantly attenuated in presence of SR extract. In conclusion, SR extract has the potency of controlling experimental atherosclerosis and can be used as promising herbal supplement in combating atherosclerosis.

In vivo oestrogenic modulation of Egr1 and Pitx1 gene expression in female rat pituitary gland.

Science.gov (United States)

Gajewska, Alina; Herman, Andrzej P; Wolińska-Witort, Ewa; Kochman, Kazimierz; Zwierzchowski, Lech

2014-12-01

EGR1 and PITX1 are transcription factors required for gonadotroph cell Lhb promoter activation. To determine changes in Egr1 and Pitx1 mRNA levels in central and peripheral pituitary stimulations, an in vivo model based on i.c.v. pulsatile (1 pulse/0.5 h over 2 h) GnRH agonist (1.5 nM buserelin) or antagonist (2 nM antide) microinjections was used. The microinjections were given to ovariectomised and 17β-oestradiol (E2) (3×20 μg), ERA (ESR1) agonist propyl pyrazole triol (PPT) (3×0.5 mg), ERB (ESR2) agonist diarylpropionitrile (DPN) (3×0.5 mg) s.c. pre-treated rats 30 min after last pulse anterior pituitaries were excised. Relative mRNA expression was determined by quantitative RT-PCR (qRT-PCR). Results revealed a gene-specific response for GnRH and/or oestrogenic stimulations in vivo. Buserelin pulses enhanced Egr1 expression by 66% in ovariectomised rats, whereas the oestradiol-supplemented+i.c.v. NaCl-microinjected group showed a 50% increase in Egr1 mRNA expression. The oestrogenic signal was transmitted via ERA (ESR1) and ERB (ESR2) activation as administration of PPT and DPN resulted in 97 and 62%, respectively, elevation in Egr1 mRNA expression. A synergistic action of GnRH agonist and 17β-oestradiol (E2) stimulation of the Egr1 gene transcription in vivo were found. GnRHR activity did not affect Pitx1 mRNA expression; regardless of NaCl, buserelin or antide i.c.v. pulses, s.c. oestrogenic supplementation (with E2, PPT or DPN) consistently decreased (by -46, -48 and -41% respectively) the Pitx1 mRNA in the anterior pituitary gland. Orchestrated Egr1 and Pitx1 activities depending on specific central and peripheral regulatory inputs could be responsible for physiologically variable Lhb gene promoter activation in vivo. © 2014 Society for Endocrinology.

K-ATP channel expression and pharmacological in vivo and in vitro studies of the K-ATP channel blocker PNU-37883A in rat middle meningeal arteries

DEFF Research Database (Denmark)

Ploug, K.B.; Boni, L.J.; Baun, M.

2008-01-01

closed cranial window model and in myograph baths, respectively. Key results: Expression studies indicate that inwardly rectifying K+ (Kir)6.1/sulphonylurea receptor (SUR) 2B is the major K-ATP channel complex in rat MMA. PNU-37883A (0.5 mg kg(-1)) significantly inhibited the in vivo dilatory effect...... of levcromakalim (0.025 mg kg(-1)), pinacidil (0.38 mg kg(-1)) and P-1075 (0.016 mg kg(-1)) in rat MMA. In vitro PNU-37883A significantly inhibited the dilatory responses of the three K-ATP channel openers in rat MMA at 10(-7) and 3 x 10(-7) M. Conclusions and implications: We suggest that Kir6.1/SUR2B...

The TetO rat as a new translational model for type 2 diabetic retinopathy by inducible insulin receptor knockdown.

Science.gov (United States)

Reichhart, Nadine; Crespo-Garcia, Sergio; Haase, Nadine; Golic, Michaela; Skosyrski, Sergej; Rübsam, Anne; Herrspiegel, Christina; Kociok, Norbert; Alenina, Natalia; Bader, Michael; Dechend, Ralf; Strauss, Olaf; Joussen, Antonia M

2017-01-01

Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy. Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats. Systemic treatment consisted of an AT1 blocker (ARB) at the onset of diabetes, following which, 4-5 weeks later the retina was analysed in vivo and ex vivo. Retinal function was assessed by Ganzfeld electroretinography (ERG). Retinal vessels in TetO rats showed differences in vessel calibre, together with gliosis. The total number and the proportion of activated mononuclear phagocytes was increased. TetO rats presented with loss of retinal ganglion cells (RGC) and ERG indicated photoreceptor malfunction. Both the inner and outer blood-retina barriers were affected. The ARB treated group showed reduced gliosis and an overall amelioration of retinal function, alongside RGC recovery, whilst no statistically significant differences in vascular and inflammatory features were detected. The TetO rat represents a promising translational model for the early neurovascular changes associated with type 2 diabetic retinopathy. ARB treatment had an effect on the neuronal component of the retina but not on the vasculature.

Fibroblast-mediated in vivo and in vitro growth promotion of tumorigenic rat thyroid carcinoma cells but not normal Fisher rat thyroid follicular cells.

Science.gov (United States)

Saitoh, Ohki; Mitsutake, Norisato; Nakayama, Toshiyuki; Nagayama, Yuji

2009-07-01

It is known that genetic abnormalities in oncogenes and/or tumor suppressor genes promote carcinogenesis. Numerous recent articles, however, have demonstrated that epithelial-stromal interaction also plays a critical role for initiation and progression of carcinoma cells. Furthermore, ionizing radiation induces alterations in the tissue microenvironments that promote carcinogenesis. There is little or no information on epithelial-stromal interaction in thyroid carcinoma cells. The objective of this study was to determine if epithelial-stromal interaction influenced the growth of thyroid carcinoma cells in vivo and in vitro and to determine if radiation had added or interacting effects. Normal Fisher rat thyroid follicular cells (FRTL5 cells) and tumorigenic rat thyroid carcinoma cells (FRTL-Tc cells) derived from FRTL5 cells were employed. The cells were injected into thyroids or subcutaneously into left flanks of rats alone or in combination with skin-derived fibroblasts. In groups of rats, fibroblasts were irradiated with 0.1 or 4 Gy x-ray 3 days before inoculation. In vitro growth of FRTL-Tc and FRTL-5 cells were evaluated using the fibroblast-conditioned medium and in a co-culture system with fibroblasts. The in vivo experiments demonstrated that FRTL-Tc cells injected intrathyroidally grew faster than those injected subcutaneously, and that admixed fibroblasts enhanced growth of subcutaneous FRTL-Tc tumors, indicating that the intrathyroidal milieu, particularly in the presence of fibroblasts, confer growth-promoting advantage to thyroid carcinoma cells. This in vivo growth-promoting effect of fibroblasts on FRTL-Tc cells was duplicated in the in vitro experiments using the fibroblast-conditioned medium. Thus, our data demonstrate that this effect is mediated by soluble factor(s), is reversible, and is comparable to that of 10% fetal bovine serum. However, normal FRTL5 cells did not respond to the fibroblast-conditioned medium. Furthermore, high- and low

Protein synthesis in the rat brain: a comparative in vivo and in vitro study in immature and adult animals

International Nuclear Information System (INIS)

Shahbazian, F.M.

1985-01-01

Rates of protein synthesis of CNS and other organs were compared in immature and adult rats by in vivo and slice techniques with administration of flooding doses of labeled precursor. The relationship between synthesis and brain region, cell type, subcellular fraction, or MW was examined. Incorporation of [ 14 C]valine into protein of CNS regions in vivo was about 1.2% per hour for immature rats and 0.6% for adults. For slices, the rates decreased significantly more in adults. In adult organs, the highest synthesis rate in vivo was found in liver (2.2% per hour) followed by kidney, spleen, lung, heart, brain, and muscle (0.5% per hour). In immature animals synthesis was highest in liver and spleen (2.5% per hour) and lowest in muscle (0.9% per hour). Slices all showed lower rates than in vivo, especially in adults. In vivo, protein synthesis rates of immature neurons and astrocytes and adult neurons exceeded those of whole brain, while that in adult astrocytes was the same. These results demonstrate a developmental difference of protein synthesis (about double in immature animals) in all brain cells, cell fractions and most brain protein. Similarly the decreased synthesis in brain slices - especially in adults, affects most proteins and structural elements

Effects of model traumatic injury on hepatic drug metabolism in the rat. IV. Glucuronidation.

Science.gov (United States)

Griffeth, L K; Rosen, G M; Rauckman, E J

1985-01-01

A previously validated small mammal trauma model, hind-limb ischemia secondary to infrarenal aortic ligation in the rat, was utilized to investigate the effects of traumatic injury on hepatic glucuronidation activity. As was previously observed with hepatic oxidative drug metabolism, model trauma resulted in a significant decrease in the in vivo glucuronidation of chloramphenicol, with a 23% drop in clearance of this drug. The effect on in vivo pharmacokinetics appeared to result from a complex interaction between trauma's differential influences on conjugating enzyme(s), deconjugating enzyme(s), and hepatic UDP-glucuronic acid levels, as well as the relative physiological importance of these variables. Hepatic UDP-glucuronyltransferase activities towards both p-nitrophenol and chloramphenicol were elevated (44-54%) after model injury when measured in native hepatic microsomes. However, microsomes which had been "activated" by treatment with Triton X-100 showed no significant difference between control and traumatized animals. Serum beta-glucuronidase activities were elevated by 58%, while hepatic beta-glucuronidase rose by about 16%. Nevertheless, in vivo deconjugation showed no significant change. Model trauma also resulted in a 46% decrease in hepatic UDP-glucuronic acid content. Thus, the observed post-traumatic depression of in vivo chloramphenicol glucuronidation could be due either to a diminished availability of a necessary cofactor (UDP-glucuronic acid) or to an alteration in enzyme kinetics or function in vivo.

A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties

Energy Technology Data Exchange (ETDEWEB)

Wang, Meng-Yu [Department of Cell Therapy, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Nestvold, Janne, E-mail: j.m.nestvold@medisin.uio.no [Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo (Norway); Rekdal, Øystein [Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø (Norway); Kvalheim, Gunnar [Department of Cell Therapy, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Fodstad, Øystein [Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway)

2017-03-15

Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. - Highlights: • Spontaneously transformed rat MSCs (rTMSCs) share characteristics with normal MSCs. • rTMSCs possess a side population, enriched with tumorigenic cells. • rTMSCs model fibrosarcoma in vivo.

A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties

International Nuclear Information System (INIS)

Wang, Meng-Yu; Nestvold, Janne; Rekdal, Øystein; Kvalheim, Gunnar; Fodstad, Øystein

2017-01-01

Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. - Highlights: • Spontaneously transformed rat MSCs (rTMSCs) share characteristics with normal MSCs. • rTMSCs possess a side population, enriched with tumorigenic cells. • rTMSCs model fibrosarcoma in vivo.

A Novel Ex Vivo Model to Investigate the Underlying Mechanisms in Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Emanuele Brai

2017-09-01

Full Text Available Currently there is no widely accepted animal model reproducing the full pathological profile of Alzheimer’s disease (AD, since the basic mechanisms of neurodegeneration are still poorly understood. We have proposed that the interaction between the α7 nicotinic acetylcholine receptor (α7-nAChR and a recently discovered toxic peptide, cleaved from the acetylcholinesterase (AChE C-terminus, could account for the aberrant processes occurring in AD. In this article we describe a new application on ex vivo model procedure, which combines the advantages of both in vivo and in vitro preparations, to study the effects of the AChE-derived peptide on the rat basal forebrain (BF. Western blot analysis showed that the levels of α7-nAChR, p-Tau and Aβ are differentially expressed upon the AChE-peptide administration, in a selective site-dependent manner. In conclusion, this methodology demonstrates the action of a novel peptide in triggering an AD-like phenotype and proposes a new ex vivo approach for manipulating and monitoring neurochemical processes contributing to neurodegeneration, in a time-dependent and site-specific manner.

Tissue-specific expression of transfected human insulin genes in pluripotent clonal rat insulinoma lines induced during passage in vivo

Energy Technology Data Exchange (ETDEWEB)

Madsen, O.D.; Andersen, L.C.; Michelsen, B.; Owerbach, D.; Larsson, L.I.; Lernmark, A.; Steiner, D.F. (Hagedorn Research Laboratory, Gentofte (Denmark))

1988-09-01

The pluripotent rat islet tumor cell line MSL-G2 expresses primarily glucagon or cholecystokinin and not insulin in vitro but changes phenotype completely after prolonged in vivo cultivation to yield small-sized hypoglycemic tumors composed almost entirely of insulin-producing beta cells. When a genomic DNA fragment containing the coding and upstream regulatory regions of the human insulin gene was stably transfected into MSL-G2 cells no measurable amounts of insulin or insulin mRNA were detected in vitro. However, successive transplantation of two transfected clones resulted in hypoglycemic tumors that efficiently coexpressed human and rat insulin as determined by human C-peptide-specific immunoreagents. These results demonstrate that cis-acting tissue-specific insulin gene enhancer elements are conserved between rat and human insulin genes. The authors propose that the in vivo differentiation of MSL-G2 cells and transfected subclones into insulin-producing cells reflects processes of natural beta-cell ontogeny leading to insulin gene expression.

Tissue-specific expression of transfected human insulin genes in pluripotent clonal rat insulinoma lines induced during passage in vivo

International Nuclear Information System (INIS)

Madsen, O.D.; Andersen, L.C.; Michelsen, B.; Owerbach, D.; Larsson, L.I.; Lernmark, A.; Steiner, D.F.

1988-01-01

The pluripotent rat islet tumor cell line MSL-G2 expresses primarily glucagon or cholecystokinin and not insulin in vitro but changes phenotype completely after prolonged in vivo cultivation to yield small-sized hypoglycemic tumors composed almost entirely of insulin-producing beta cells. When a genomic DNA fragment containing the coding and upstream regulatory regions of the human insulin gene was stably transfected into MSL-G2 cells no measurable amounts of insulin or insulin mRNA were detected in vitro. However, successive transplantation of two transfected clones resulted in hypoglycemic tumors that efficiently coexpressed human and rat insulin as determined by human C-peptide-specific immunoreagents. These results demonstrate that cis-acting tissue-specific insulin gene enhancer elements are conserved between rat and human insulin genes. The authors propose that the in vivo differentiation of MSL-G2 cells and transfected subclones into insulin-producing cells reflects processes of natural beta-cell ontogeny leading to insulin gene expression

In vivo detection of dynamics of elements in a living rat using multitracer technique

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Ken-ichiro; Ui, Iori; Endo, Kazutoyo [Showa Pharmaceutical Univ., Dept. of Physical Chemistry, Machida, Tokyo (Japan); Hirunuma, Rieko; Enomoto, Shuichi [The Inst. of Physical and Chemical Research, Cyclotron Center, Division of Radioisotope Technology, Wako, Saitama (Japan)

2002-04-01

In vivo detection technique for radioactivity of the nuclide in the multitracer intravenously administered to a living rat was proposed using a special setting of lead slit and high-purity Ge semiconducting detector. In vivo time courses of the relative distribution of {sup 7}Be, 4{sup 8}V, {sup 54}Mn, {sup 58}Co, {sup 65}Zn, {sup 74}As, {sup 75}Se, {sup 83}Rb, {sup 85}Sr, and {sup 88}Y in upper abdomen and head of six week old male Wistar rats were analyzed. The dynamics of the elements were estimated using the relative distribution of {sup 74}As as base line of blood concentration, since exogenous arsenic tracer is mainly taken into red blood cell. In the head, elements distributed mainly in bones or muscles except for Co and Se, while these elements in blood. In the upper abdomen, Mn, Co, Zn, Se, Rb, V, and Y are distributed in to the liver, which is a main organ for accumulating metals. It is the first report that dynamics of biotrace elements within an hour after administration was non-invasively obtained in living animal. (author)

Effect of the spider toxin Tx3-3 on spinal processing of sensory information in naive and neuropathic rats: an in vivo electrophysiological study.

Science.gov (United States)

Dalmolin, Gerusa D; Bannister, Kirsty; Gonçalves, Leonor; Sikandar, Shafaq; Patel, Ryan; Cordeiro, Marta do Nascimento; Gomez, Marcus Vinícius; Ferreira, Juliano; Dickenson, Anthony H

2017-07-01

Drugs that counteract nociceptive transmission in the spinal dorsal horn preferentially after nerve injury are being pursued as possible neuropathic pain treatments. In a previous behavioural study, the peptide toxin Tx3-3, which blocks P/Q- and R-type voltage-gated calcium channels, was effective in neuropathic pain models. In the present study, we aimed to investigate the effect of Tx3-3 on dorsal horn neuronal responses in rats under physiological conditions and neuropathic pain condition induced by spinal nerve ligation (SNL). In vivo electrophysiological recordings of dorsal horn neuronal response to electrical and natural (mechanical and thermal) stimuli were made in rats under normal physiological state (naive rats) or after the SNL model of neuropathic pain. Tx3-3 (0.3-100 pmol/site) exhibited greater inhibitory effect on electrical-evoked neuronal response of SNL rats than naive rats, inhibiting nociceptive C-fibre and Aδ-fibre responses only in SNL rats. The wind-up of neurones, a measurement of spinal cord hyperexcitability, was also more susceptible to a dose-related inhibition by Tx3-3 after nerve injury. Moreover, Tx3-3 exhibited higher potency to inhibit mechanical- and thermal-evoked neuronal response in conditions of neuropathy. Tx3-3 mediated differential inhibitory effect under physiological and neuropathic conditions, exhibiting greater potency in conditions of neuropathic pain.

Cortical substrate oxidation during hyperketonemia in the fasted anesthetized rat in vivo

OpenAIRE

Jiang, Lihong; Mason, Graeme F; Rothman, Douglas L; de Graaf, Robin A; Behar, Kevin L

2011-01-01

Ketone bodies are important alternate brain fuels, but their capacity to replace glucose and support neural function is unclear. In this study, the contributions of ketone bodies and glucose to cerebral cortical metabolism were measured in vivo in halothane-anesthetized rats fasted for 36 hours (n=6) and receiving intravenous [2,4-13C2]--β-hydroxybutyrate (BHB). Time courses of 13C-enriched brain amino acids (glutamate-C4, glutamine-C4, and glutamate and glutamine-C3) were measured at 9.4 Tes...

A novel survival model of cardioplegic arrest and cardiopulmonary bypass in rats: a methodology paper

Directory of Open Access Journals (Sweden)

Podgoreanu Mihai V

2008-08-01

Full Text Available Abstract Background Given the growing population of cardiac surgery patients with impaired preoperative cardiac function and rapidly expanding surgical techniques, continued efforts to improve myocardial protection strategies are warranted. Prior research is mostly limited to either large animal models or ex vivo preparations. We developed a new in vivo survival model that combines administration of antegrade cardioplegia with endoaortic crossclamping during cardiopulmonary bypass (CPB in the rat. Methods Sprague-Dawley rats were cannulated for CPB (n = 10. With ultrasound guidance, a 3.5 mm balloon angioplasty catheter was positioned via the right common carotid artery with its tip proximal to the aortic valve. To initiate cardioplegic arrest, the balloon was inflated and cardioplegia solution injected. After 30 min of cardioplegic arrest, the balloon was deflated, ventilation resumed, and rats were weaned from CPB and recovered. To rule out any evidence of cerebral ischemia due to right carotid artery ligation, animals were neurologically tested on postoperative day 14, and their brains histologically assessed. Results Thirty minutes of cardioplegic arrest was successfully established in all animals. Functional assessment revealed no neurologic deficits, and histology demonstrated no gross neuronal damage. Conclusion This novel small animal CPB model with cardioplegic arrest allows for both the study of myocardial ischemia-reperfusion injury as well as new cardioprotective strategies. Major advantages of this model include its overall feasibility and cost effectiveness. In future experiments long-term echocardiographic outcomes as well as enzymatic, genetic, and histologic characterization of myocardial injury can be assessed. In the field of myocardial protection, rodent models will be an important avenue of research.

Mathematical model of glucose-insulin homeostasis in healthy rats.

Science.gov (United States)

Lombarte, Mercedes; Lupo, Maela; Campetelli, German; Basualdo, Marta; Rigalli, Alfredo

2013-10-01

According to the World Health Organization there are over 220 million people in the world with diabetes and 3.4 million people died in 2004 as a consequence of this pathology. Development of an artificial pancreas would allow to restore control of blood glucose by coupling an infusion pump to a continuous glucose sensor in the blood. The design of such a device requires the development and application of mathematical models which represent the gluco-regulatory system. Models developed by other research groups describe very well the gluco-regulatory system but have a large number of mathematical equations and require complex methodologies for the estimation of its parameters. In this work we propose a mathematical model to study the homeostasis of glucose and insulin in healthy rats. The proposed model consists of three differential equations and 8 parameters that describe the variation of: blood glucose concentration, blood insulin concentration and amount of glucose in the intestine. All parameters were obtained by setting functions to the values of glucose and insulin in blood obtained after oral glucose administration. In vivo and in silico validations were performed. Additionally, a qualitative analysis has been done to verify the aforementioned model. We have shown that this model has a single, biologically consistent equilibrium point. This model is a first step in the development of a mathematical model for the type I diabetic rat. Copyright © 2013 Elsevier Inc. All rights reserved.

An in vivo magnetic resonance spectroscopy study of the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats

NARCIS (Netherlands)

Janssens, S.; Ciapaite, J.; Wolters, J.C.; van Riel, N.A.; Nicolay, K.; Prompers, J.J.

2017-01-01

We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or

An In Vivo Magnetic Resonance Spectroscopy Study of the Effects of Caloric and Non-Caloric Sweeteners on Liver Lipid Metabolism in Rats

NARCIS (Netherlands)

Janssens, Sharon; Ciapaite, Jolita; Wolters, Justina C.; van Riel, Natal A.; Nicolay, Klaas; Prompers, Jeanine J.

2017-01-01

We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or

Development of diabetes does not alter behavioral and molecular circadian rhythms in a transgenic rat model of type 2 diabetes mellitus.

Science.gov (United States)

Qian, Jingyi; Thomas, Anthony P; Schroeder, Analyne M; Rakshit, Kuntol; Colwell, Christopher S; Matveyenko, Aleksey V

2017-08-01

Metabolic state and circadian clock function exhibit a complex bidirectional relationship. Circadian disruption increases propensity for metabolic dysfunction, whereas common metabolic disorders such as obesity and type 2 diabetes (T2DM) are associated with impaired circadian rhythms. Specifically, alterations in glucose availability and glucose metabolism have been shown to modulate clock gene expression and function in vitro; however, to date, it is unknown whether development of diabetes imparts deleterious effects on the suprachiasmatic nucleus (SCN) circadian clock and SCN-driven outputs in vivo. To address this question, we undertook studies in aged diabetic rats transgenic for human islet amyloid polypeptide, an established nonobese model of T2DM (HIP rat), which develops metabolic defects closely recapitulating those present in patients with T2DM. HIP rats were also cross-bred with a clock gene reporter rat model (Per1:luciferase transgenic rat) to permit assessment of the SCN and the peripheral molecular clock function ex vivo. Utilizing these animal models, we examined effects of diabetes on 1 ) behavioral circadian rhythms, 2 ) photic entrainment of circadian activity, 3 ) SCN and peripheral tissue molecular clock function, and 4 ) melatonin secretion. We report that circadian activity, light-induced entrainment, molecular clockwork, as well as melatonin secretion are preserved in the HIP rat model of T2DM. These results suggest that despite the well-characterized ability of glucose to modulate circadian clock gene expression acutely in vitro, SCN clock function and key behavioral and physiological outputs appear to be preserved under chronic diabetic conditions characteristic of nonobese T2DM. Copyright © 2017 the American Physiological Society.

Histological study of subcutaneous fat at NIR laser treatment of the rat skin in vivo

Science.gov (United States)

Yanina, I. Y.; Svenskaya, Yu. I.; Navolokin, N. A.; Matveeva, O. V.; Bucharskaya, A. B.; Maslyakova, G. N.; Gorin, D. A.; Sukhorukov, G. B.; Tuchin, V. V.

2015-07-01

The goal of this work is to quantify impact of in vivo photochemical treatment using indocyanine green (ICG) or encapsulated ICG and NIR laser irradiation through skin of rat with obesity by the follow up tissue sampling and histochemistry. After 1 hour elapsed since 1-min light exposure samples of rat skin with subcutaneous tissue of thickness of 1.5-2.5 mm were taken by surgery from rats within marked 4-zones of the skin site. For hematoxylin-eosin histological examination of excised tissue samples, fixation was carried out by 10%-formaldehyde solution. For ICG and encapsulated ICG subcutaneous injection and subsequent 1-min diode laser irradiation with power density of 8 W/cm2, different necrotic regions with lipolysis of subcutaneous fat were observed. The obtained data can be used for safe layer-by-layer laser treatment of obesity and cellulite.

Induction of cytochromes P450 1A1 and 1A2 suppresses formation of DNA adducts by carcinogenic aristolochic acid I in rats in vivo

International Nuclear Information System (INIS)

Dračínská, Helena; Bárta, František; Levová, Kateřina; Hudecová, Alena; Moserová, Michaela; Schmeiser, Heinz H.; Kopka, Klaus; Frei, Eva; Arlt, Volker M.; Stiborová, Marie

2016-01-01

Highlights: • Oxidation and reduction of aristolochic acid I (AAI) dictate its (geno)toxicity in vivo. • Cytochrome P450 (CYP) 1A1 and 1A2 are induced in rats treated with Sudan I and AAI. • Induced CYP1A enzyme activity resulted in decreased AAI-DNA adduct levels in vivo. • CYP1A1 and 1A2 mainly detoxify AAI and attenuate its genotoxicity in vivo. - Abstract: Aristolochic acid I (AAI) is a natural plant alkaloid causing aristolochic acid nephropathy, Balkan endemic nephropathy and their associated urothelial malignancies. One of the most efficient enzymes reductively activating AAI to species forming AAI-DNA adducts is cytosolic NAD(P)H:quinone oxidoreductase 1. AAI is also either reductively activated or oxidatively detoxified to 8-hydroxyaristolochic acid (AAIa) by microsomal cytochrome P450 (CYP) 1A1 and 1A2. Here, we investigated which of these two opposing CYP1A1/2-catalyzed reactions prevails in AAI metabolism in vivo. The formation of AAI-DNA adducts was analyzed in liver, kidney and lung of rats treated with AAI, Sudan I, a potent inducer of CYP1A1/2, or AAI after pretreatment with Sudan I. Compared to rats treated with AAI alone, levels of AAI-DNA adducts determined by the 32 P-postlabeling method were lower in liver, kidney and lung of rats treated with AAI after Sudan I. The induction of CYP1A1/2 by Sudan I increased AAI detoxification to its O-demethylated metabolite AAIa, thereby reducing the actual amount of AAI available for reductive activation. This subsequently resulted in lower AAI-DNA adduct levels in the rat in vivo. Our results demonstrate that CYP1A1/2-mediated oxidative detoxification of AAI is the predominant role of these enzymes in rats in vivo, thereby suppressing levels of AAI-DNA adducts.

Administration of exercise-conditioned plasma alters muscle catalase kinetics in rat: An argument for in vivo-like Km instead of in vitro-like Vmax

Directory of Open Access Journals (Sweden)

Aristidis S. Veskoukis

2018-05-01

Full Text Available Maximal velocity (Vmax is a well established biomarker for the assessment of tissue redox status. There is scarce evidence, though, that it does not probably reflect sufficiently in vivo tissue redox profile. Instead, the Michaelis constant (Km could more adequately image tissue oxidative stress and, thus, be a more physiologically relevant redox biomarker. Therefore, the aim of the present study was to side-by-side compare Vmax and Km of an antioxidant enzyme after implementing an in vivo set up that induces alterations in tissue redox status. Forty rats were divided into two groups including rats injected with blood plasma originating from rats that had previously swam until exhaustion and rats injected with blood plasma originating from sedentary rats. Tail-vein injections were performed daily for 21 days. Catalase Vmax and Km measured in gastrocnemius muscle were increased after administration of the exercise-conditioned plasma, denoting enhancement of the enzyme activity but impairment of its affinity for the substrate, respectively. These alterations are potential adaptations stimulated by the administered plasma pointing out that blood is an active fluid capable of regulating tissue homeostasis. Our findings suggest that Km adequately reflects in vivo modifications of skeletal muscle catalase and seems to surpass Vmax regarding its physiological relevance and biological interpretation. In conclusion, Km can be regarded as an in vivo-like biomarker that satisfactorily images the intracellular environment, as compared to Vmax that could be aptly parallelized with a biomarker that describes tissue oxidative stress in an in vitro manner.

Infection in a rat model reactivates attenuated virulence after long-term axenic culture of Acanthamoeba spp

Directory of Open Access Journals (Sweden)

Carolina De Marco Verissimo

2013-11-01

Full Text Available Prolonged culturing of many microorganisms leads to the loss of virulence and a reduction of their infective capacity. However, little is known about the changes in the pathogenic strains of Acanthamoeba after long culture periods. Our study evaluated the effect of prolonged culturing on the invasiveness of different isolates of Acanthamoeba in an in vivo rat model. ATCC strains of Acanthamoeba, isolates from the environment and clinical cases were evaluated. The in vivo model was effective in establishing the infection and differentiating the pathogenicity of the isolates and re-isolates. The amoebae cultured in the laboratory for long periods were less virulent than those that were recently isolated, confirming the importance of passing Acanthamoeba strains in animal models.

4R-Cembranoid Improves Outcomes after 6-Hydroxydopamine Challenge in Both In vitro and In vivo Models of Parkinson's Disease

Directory of Open Access Journals (Sweden)

Jing Hu

2017-05-01

Full Text Available (1S, 2E, 4R, 6R,-7E, 11E-2, 7, 11-cembratriene-4, 6-diol (4R is one of the cembranoids found in tobacco leaves. Previous studies have found that 4R protected acute rat hippocampal slices against neurotoxicity induced by N-methyl-D-aspartate (NMDA and against the toxic organophosphorus compounds paraoxon and diisopropylfluorophosphate (DFP. Furthermore, in vivo, 4R reduced the infarct size in a rodent ischemic stroke model and neurodegeneration caused by DFP. The present study expanded our previous study by focusing on the effect of 4R in Parkinson's disease (PD and elucidating its underlying mechanisms using 6-hydroxydopamine (6-OHDA-induced injury models. We found that 4R exhibited significant neuroprotective activity in the rat unilateral 6-OHDA-induced PD model in vivo. The therapeutic effect was evident both at morphological and behavioral levels. 4R (6 and 12 mg/kg treatments significantly improved outcomes of 6-OHDA-induced PD in vivo as indicated by reducing forelimb asymmetry scores and corner test scores 4 weeks after injection of 6-OHDA (p < 0.05. The therapeutic effect of 4R was also reflected by decreased depletion of tyrosine hydroxylase (TH in the striatum and substantia nigra (SN on the side injected with 6-OHDA. TH expression was 70.3 and 62.8% of the contralateral side in striatum and SN, respectively, after 6 mg/kg 4R treatment; furthermore, it was 80.1 and 79.3% after treatment with 12 mg/kg of 4R. In the control group, it was 51.9 and 23.6% of the contralateral striatum and SN (p < 0.05. Moreover, 4R also protected differentiated neuro-2a cells from 6-OHDA-induced cytotoxicity in vitro. The activation of p-AKT and HAX-1, and inhibition of caspase-3 and endothelial inflammation, were involved in 4R-mediated protection against 6-OHDA-induced injury. In conclusion, the present study indicates that 4R shows a therapeutic effect in the rat 6-OHDA-induced PD model in vivo and in 6-OHDA-challenged neuro-2a cells in vitro.

Rivaroxaban attenuates thrombosis by targeting the NF-κB signaling pathway in a rat model of deep venous thrombus.

Science.gov (United States)

Ma, Junhao; Li, Xinxi; Wang, Yang; Yang, Zhenwei; Luo, Jun

2017-12-01

Anticoagulant therapy is commonly used for the prevention and treatment of patients with deep venous thrombus. Evidence has shown that rivaroxaban is a potential oral anticoagulant drug for the acute treatment of venous thromboembolism. However, the rivaroxaban-mediated molecular mechanism involved in the progression of deep venous thrombosis has not been investigated. In the present study, we investigated the efficacy of rivaroxaban and the underlying signaling pathways in the prevention and treatment of rats with deep venous thrombosis. A rat model with deep vein thrombus formation was established and received treatment with rivaroxaban or PBS as control. The thrombin-activatable fibrinolysis inhibitor (TAFI) and plasminogen activator inhibitor-1 (PAI-1) were analyzed both in vitro and in vivo. The progression of thrombosis and stroke was evaluated after treatment with rivaroxaban or PBS. Nuclear factor-κB (NF-κB) signaling pathway in venous endothelial cells and in the rat model of deep venous thrombus was assessed. The therapeutic effects of rivaroxaban were evaluated as determined by changes in deep venous thrombosis in the rat model. Our results showed that rivaroxaban markedly inhibited TAFI and PAI-1 expression levels, neutrophils, tissue factor, neutrophil extracellular traps (NETs), myeloperoxidase and macrophages in venous endothelial cells and in the rat model of deep venous thrombus. Expression levels of ADP, PAIs, von Willebrand factor (vWF) and thromboxane were downregulated in vein endothelial cells and in serum from the experimental rats. Importantly, the incidences of inferior vena cava filter thrombus were protected by rivaroxaban during heparin-induced thrombolysis deep venous thrombosis in the rat model. We observed that activity of the NF-κB signaling pathway was inhibited by rivaroxaban in vein endothelial cells both in vitro and in vivo. Notably, immunohistology indicated that rivaroxaban attenuated deep venous thrombosis and the

Water extracts of cabbage and kale inhibit ex vivo H2O2-induced DNA damage but not rat hepatocarcinogenesis

Directory of Open Access Journals (Sweden)

M.A. Horst

2010-03-01

Full Text Available The chemopreventive potential of water extracts of the Brassica vegetables cabbage and kale was evaluated by administering their aqueous extracts in drinking water ad libitum to Wistar rats submitted to Ito’s hepatocarcinogenesis model (CB group and K group, respectively - 14 rats per group. Animals submitted to this same model and treated with water were used as controls (W group - 15 rats. Treatment with the vegetable extracts did not inhibit (P > 0.05 placental glutathione S-transferase-positive preneoplastic lesions (PNL. The number of apoptotic bodies did not differ (P > 0.05 among the experimental groups. Ex vivo hydrogen peroxide treatment of rat livers resulted in lower (P < 0.05 DNA strand breakage in cabbage- (107.6 ± 7.8 µm and kale- (110.8 ± 10.0 µm treated animals compared with control (120.9 ± 12.7 µm, as evaluated by the single cell gel (comet assay. Treatment with cabbage (2 ± 0.3 µg/g or kale (4 ± 0.2 µg/g resulted in increased (P < 0.05 hepatic lutein concentration compared with control (0.5 ± 0.07 µg/g. Despite the absence of inhibitory effects of cabbage and kale aqueous extracts on PNL, these Brassica vegetables presented protection against DNA damage, an effect possibly related to increased hepatic lutein concentrations. However, it must be pointed out that the cause-effect relationship between lutein levels and protection is hypothetical and remains to be demonstrated.

Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

International Nuclear Information System (INIS)

Jantscheff, Peter; Esser, Norbert; Geipel, Andreas; Woias, Peter; Ziroli, Vittorio; Goldschmidtboing, Frank; Massing, Ulrich

2011-01-01

The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented

Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

Energy Technology Data Exchange (ETDEWEB)

Jantscheff, Peter, E-mail: jantscheff@tumorbio.uni-freiburg.de [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Esser, Norbert [ProQinase GmbH, Breisacher Str. 117, D-79106 Freiburg (Germany); Geipel, Andreas; Woias, Peter [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Ziroli, Vittorio [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Goldschmidtboing, Frank [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Massing, Ulrich [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany)

2011-06-17

The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

Metastasizing, Luciferase Transduced MAT‑Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

Directory of Open Access Journals (Sweden)

Peter Woias

2011-06-01

Full Text Available The most fatal outcomes of prostate carcinoma (PCa result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24, spleen (3/24, kidney (4/24, liver (5/24, and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively. Preliminary data of orthotopic implantation (three animals showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes. Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4, lung (3/6 or lumbar spine (0/2, as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

In vivo genotoxicity of furan in F344 rats at cancer bioassay doses

International Nuclear Information System (INIS)

Ding, Wei; Petibone, Dayton M.; Latendresse, John R.; Pearce, Mason G.; Muskhelishvili, Levan; White, Gene A.; Chang, Ching-Wei; Mittelstaedt, Roberta A.; Shaddock, Joseph G.; McDaniel, Lea P.; Doerge, Daniel R.; Morris, Suzanne M.; Bishop, Michelle E.; Manjanatha, Mugimane G.; Aidoo, Anane; Heflich, Robert H.

2012-01-01

Furan, a potent rodent liver carcinogen, is found in many cooked food items and thus represents a human cancer risk. Mechanisms for furan carcinogenicity were investigated in male F344 rats using the in vivo Comet and micronucleus assays, combined with analysis of histopathological and gene expression changes. In addition, formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III (EndoIII)-sensitive DNA damage was monitored as a measure of oxidative DNA damage. Rats were treated by gavage on four consecutive days with 2, 4, and 8 mg/kg bw furan, doses that were tumorigenic in 2-year cancer bioassays, and with two higher doses, 12 and 16 mg/kg. Rats were killed 3 h after the last dose, a time established as producing maximum levels of DNA damage in livers of furan-treated rats. Liver Comet assays indicated that both DNA strand breaks and oxidized purines and pyrimidines increased in a near-linear dose-responsive fashion, with statistically significant increases detected at cancer bioassay doses. No DNA damage was detected in bone marrow, a non-target tissue for cancer, and peripheral blood micronucleus assays were negative. Histopathological evaluation of liver from furan-exposed animals produced evidence of inflammation, single-cell necrosis, apoptosis, and cell proliferation. In addition, genes related to apoptosis, cell-cycle checkpoints, and DNA-repair were expressed at a slightly lower level in the furan-treated livers. Although a mixed mode of action involving direct DNA binding cannot be ruled out, the data suggest that furan induces cancer in rat livers mainly through a secondary genotoxic mechanism involving oxidative stress, accompanied by inflammation, cell proliferation, and toxicity. -- Highlights: ► Furan is a potent rodent liver carcinogen and represents a human cancer risk. ► Furan induces DNA damage in rat liver at cancer bioassay doses. ► Furan induces oxidative stress, inflammation and cell proliferation in rat liver. ► Expression of

Effect of nutritional status on oxidative stress in an ex vivo perfused rat liver.

Science.gov (United States)

Stadler, Michaela; Nuyens, Vincent; Seidel, Laurence; Albert, Adelin; Boogaerts, Jean G

2005-11-01

Normothermic ischemia-reperfusion is a determinant in liver injury occurring during surgical procedures, ischemic state, and multiple organ failure. The preexisting nutritional status of the liver might contribute to the extent of tissue injury and primary nonfunction. The aim of this study was to determine the role of starvation on hepatic ischemia-reperfusion injury in normal rat livers. Rats were randomly divided into two groups: one had free access to food, the other was fasted for 16 h. The portal vein was cannulated, and the liver was removed and perfused in a closed ex vivo system. Two modes of perfusion were applied in each series of rats, fed and fasting. In the ischemia-reperfusion mode, the experiment consisted of perfusion for 15 min, warm ischemia for 60 min, and reperfusion during 60 min. In the nonischemia mode, perfusion was maintained during the 135-min study period. Five rats were included in each experimental condition, yielding a total of 20 rats. Liver enzymes, potassium, glucose, lactate, free radicals, i.e., dienes and trienes, and cytochrome c were analyzed in perfusate samples. The proportion of glycogen in hepatocytes was determined in tissue biopsies. Transaminases, lactate dehydrogenase, potassium, and free radical concentrations were systematically higher in fasting rats in both conditions, with and without ischemia. Cytochrome c was higher after reperfusion in the fasting rats. Glucose and lactate concentrations were greater in the fed group. The glycogen content decreased in both groups during the experiment but was markedly lower in the fasting rats. In fed rats, liver injury was moderate, whereas hepatocytes integrity was notably impaired both after continuous perfusion and warm ischemia in fasting animals. Reduced glycogen store in hepatocytes may explain reduced tolerance.

In vivo and in vitro studies of cartilage differentiation in altered gravities

Science.gov (United States)

Montufar-Solis, D.; Duke, P. J.; D'Aunno, D.

The in vivo model our laboratory uses for studies of cartilage differentiation in space is the rat growth plate. Differences between missions, and in rat age and recovery times, provided differing results from each mission. However, in all missions, proliferation and differentiation of chondrocytes in the epiphyseal plate of spaceflown rats was altered as was matrix organization. In vitro systems, necessary complements to in vivo work, provide some advantages over the in vivo situation. In vitro, centrifugation of embryonic limb buds suppressed morphogenesis due to precocious differentiation, and changes in the developmental pattern suggest the involvement of Hox genes. In space, embryonic mouse limb mesenchyme cells differentiating in vitro on IML-1 had smoother membranes and lacked matrix seen in controls. Unusual formations, possibly highly ruffled membranes, were found in flight cultures. These results, coupled with in vivo centrifugation studies, show that in vivo or in vitro, the response of chondrocytes to gravitational changes follows Hert's curve as modified by Simon, i.e. decreased loading decreases differentiation, and increased loading speeds it up, but only to a point. After that, additional increases again slow down chondrogenesis.

In vivo assessment of the impact of efflux transporter on oral drug absorption using portal vein-cannulated rats.

Science.gov (United States)

Matsuda, Yoshiki; Konno, Yoshihiro; Hashimoto, Takashi; Nagai, Mika; Taguchi, Takayuki; Satsukawa, Masahiro; Yamashita, Shinji

2013-08-01

The purpose of this study was to evaluate the impact of intestinal efflux transporters on the in vivo oral absorption process. Three model drugs-fexofenadine (FEX), sulfasalazine (SASP), and topotecan (TPT)-were selected as P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and P-gp and BCRP substrates, respectively. The drugs were orally administered to portal vein-cannulated rats after pretreatment with zosuquidar (ZSQ), P-gp inhibitor, and/or Ko143, BCRP inhibitor. Intestinal availability (Fa·Fg) of the drugs was calculated from the difference between portal and systemic plasma concentrations. When rats were orally pretreated with ZSQ, Fa·Fg of FEX increased 4-fold and systemic clearance decreased to 75% of the control. In contrast, intravenous pretreatment with ZSQ did not affect Fa·Fg of FEX, although systemic clearance decreased significantly. These data clearly show that the method presented herein using portal vein-cannulated rats can evaluate the effects of intestinal transporters on Fa·Fg of drugs independently of variable systemic clearance. In addition, it was revealed that 71% of FEX taken up into enterocytes underwent selective efflux via P-gp to the apical surface, while 79% of SASP was effluxed by Bcrp. In the case of TPT, both transporters were involved in its oral absorption. Quantitative analysis indicated a 3.5-fold higher contribution from Bcrp than P-gp. In conclusion, the use of portal vein-cannulated rats enabled the assessment of the impact of efflux transporters on intestinal absorption of model drugs. This experimental system is useful for clarifying the cause of low bioavailability of various drugs.

Kinetics of potassium, rubidium and cesium in rat

International Nuclear Information System (INIS)

Natsuhori, Masahiro; Kosaka, Shigetoshi; Nishikawa, Miki; Okida, Masato; Ito, Nobuhiko

1998-01-01

Apparent incorporation rates of K and Rb into red blood cells were investigated in rats in consideration of passive diffusion to clarify in vivo kinetics of alkali metals. First, the incorporation rates of K and Rb into blood cells were determined by incubating blood samples from SD rat with 42 K and 86 Rb-buffers. And parameters involving in these incorporations such as Vmax (maximum rate of active transport), {S} (substrate concentration), Km (Michaelis constant), n (cooperativity of active transport), etc. were evaluated based on the time-course changes in K and Rb incorporation. Then, K and Rb were given to SD rats and the respective levels in plasma, red blood cells and urine were determined. The parameters were evaluated based on the time course changes in these levels by using compartment model. Similarly, the kinetics of Cs were investigated in rats. The absorption, distribution and disappearance of alkali metals were investigated in vivo to compare in vivo kinetics among the metals. By applying the kinetic parameters analyzed, Cs kinetics, in vivo could be estimated and Cs intake was able to be also estimated by determining the Cs levels of blood cells, urine and plasma. (M.N.)

Specific Schistosoma mansoni rat T cell clones. I. Generation and functional analysis in vitro and in vivo.

Science.gov (United States)

Pestel, J; Dissous, C; Dessaint, J P; Louis, J; Engers, H; Capron, A

1985-06-01

In an attempt to determine the role of schistosome-specific T cells in the immune mechanisms developed during schistosomiasis, Schistosoma mansoni-specific T cells and clones were generated in vitro and some of their functions analyzed in vitro and in vivo in the fischer rat model. The data presented here can be summarized as follows: a) Lymph node cells (LNC) from rats primed with the excretory/secretory antigens-incubation products (IPSm) of adult worms proliferate in vitro only in response to the homologous schistosome antigens and not to unrelated antigens (Ag) such as ovalbumin (OVA) or Dipetalonema viteae and Fasciola hepatica parasite extracts. b) After in vitro restimulation of the primed LNC population with IPSm in the presence of antigen-presenting cells (APC) and maintenance in IL 2-containing medium, the frequency of IPSm-specific T cells is increased and the T cells can be restimulated only in the presence of APC possessing the same major histocompatibility complex (MHC) antigens. c) Following appropriate limiting dilution assays (LDA) (1 cell/well), 10 IPSm-specific T cell clones were obtained, and two of four maintained in culture were tested for their helper activity because they expressed only the W3/13+ W3/25+ surface phenotypes. d) The two highly proliferating IPSm-specific T cell clones (G5 and E23) exhibit an IPSm-dependent helper activity, as shown by the increase in IgG production by IPSm-primed B cells. e) IPSm-T cell clone (G5) as well as IPSm-T cell lines when injected in S. mansoni-infested rats can exert an in vivo helper activity, which is characterized by an accelerated production of IgG antibodies specific for the previously identified 30 to 40 kilodaltons (kd) schistosomula surface antigens (Ag). As recent studies have demonstrated that rat monoclonal antibodies recognize some incubation products of adult S. mansoni as well as one of the 30 to 40 kd schistosomula surface antigens, and taking into account the fact that the T cell

Reflection on design and testing of pancreatic alpha-amylase inhibitors: an in silico comparison between rat and rabbit enzyme models

Directory of Open Access Journals (Sweden)

Khalil-Moghaddam Shiva

2012-11-01

Full Text Available Abstract Background Inhibitors of pancreatic alpha-amylase are potential drugs to treat diabetes and obesity. In order to find compounds that would be effective amylase inhibitors, in vitro and in vivo models are usually used. The accuracy of models is limited, but these tools are nonetheless valuable. In vitro models could be used in large screenings involving thousands of chemicals that are tested to find potential lead compounds. In vivo models are still used as preliminary mean of testing compounds behavior in the whole organism. In the case of alpha-amylase inhibitors, both rats and rabbits could be chosen as in vivo models. The question was which animal could present more accuracy with regard to its pancreatic alpha-amylase. Results As there is no crystal structure of these enzymes, a molecular modeling study was done in order to compare the rabbit and rat enzymes with the human one. The overall result is that rabbit enzyme could probably be a better choice in this regard, but in the case of large ligands, which could make putative interactions with the −4 subsite of pancreatic alpha-amylase, interpretation of results should be made cautiously. Conclusion Molecular modeling tools could be used to choose the most suitable model enzyme that would help to identify new enzyme inhibitors. In the case of alpha-amylase, three-dimensional structures of animal enzymes show differences with the human one which should be taken into account when testing potential new drugs.

In vivo autoradiographic demonstration of β-adrenergic binding sites in adult rat type II alveolar epithelial cells

International Nuclear Information System (INIS)

Smith, D.M.; Sidhu, M.K.

1984-01-01

Adult male rats were injected intravenously with the muscarinic binding probe 3 H-Quinuclidinyl benzilate (QNB) or the β-adrenergic probe 3 H-dihydroalprenolol (DHA). Other rats were pre-treated with an intraperitoneal injection of a 500-fold excess of L-isoproterenol prior to the DHA. Light microscopic autoradiography of 0.5 μm sections of lung from the QNB group demonstrated very little labelling even after 6 months of exposure. In constrast, trachealis smooth muscle from these animals contained substantial labelling. Autoradiographs of lung from rats injected with DHA demonstrated labelling which was well localized over alveolar septa and concentrated over the cytoplasm of type II cells. Quantitative analysis of labelling in the DHA groups indicated a significant reduction of labelling in animals treated with L-isoproterenol prior to DHA, in both the alveolar parenchyma in general and over type II cells. The results of this study provide morphologic evidence for the uptake and specific binding of β-adrenergic antagonists by the adult lung in vivo, while failing to demonstrate similar binding of a muscarinic probe. In addition, the results demonstrate specific β-adrenergic receptors on type II cells in vivo and substantiate the view of a direct effect of β-adrenergic agonists on alveolar type II cells

In vivo sodium, potassium, and sperm concentrations in the rat epididymis.

Science.gov (United States)

Turner, T T; Hartmann, P K; Howards, S S

1977-02-01

In vivo samples of epididymal fluids were obtained through the use of micropuncture techniques. Microsamples from four areas of the rat epididymis were analyzed for Na+ and K+ concentrations and for sperm density. Na+ values declined significantly from caput to corpus epididymidis (P less than 0.01), while K+ and sperm concentrations increased significantly (P less than 0.01). A large water loss from the epididymal lumen was calculated, as well as net losses of both cations. Water losses may be explained on the basis of an active Na+ pump; however, the effect of the absolute values of epididymal Na+ and K+ concentrations on sperm motility and fertility remains unresolved.

REDUCTION OF EGP-2-POSITIVE PULMONARY METASTASES BY BISPECIFIC-ANTIBODY-REDIRECTED T-CELLS IN AN IMMUNOCOMPETENT RAT MODEL

NARCIS (Netherlands)

KROESEN, BJ; HELFRICH, W; BAKKER, A; WUBBENA, AS; BAKKER, H; KAL, HB; THE, TH; DELEIJ, L

1995-01-01

Effectiveness of bispecific-monoclonal-antibody (B5MAb)-mediated cellular anti-tumour activity was evaluated in vitro and in vivo in relation to the additional need for T-cell activation in a new immunocompetent rat tumour model. L37 tumour cells, derived from a squamous-cell carcinoma of the lung

Administration of exercise-conditioned plasma alters muscle catalase kinetics in rat: An argument for in vivo-like Km instead of in vitro-like Vmax.

Science.gov (United States)

Veskoukis, Aristidis S; Paschalis, Vassilis; Kyparos, Antonios; Nikolaidis, Michalis G

2018-05-01

Maximal velocity (V max ) is a well established biomarker for the assessment of tissue redox status. There is scarce evidence, though, that it does not probably reflect sufficiently in vivo tissue redox profile. Instead, the Michaelis constant (K m ) could more adequately image tissue oxidative stress and, thus, be a more physiologically relevant redox biomarker. Therefore, the aim of the present study was to side-by-side compare V max and K m of an antioxidant enzyme after implementing an in vivo set up that induces alterations in tissue redox status. Forty rats were divided into two groups including rats injected with blood plasma originating from rats that had previously swam until exhaustion and rats injected with blood plasma originating from sedentary rats. Tail-vein injections were performed daily for 21 days. Catalase V max and K m measured in gastrocnemius muscle were increased after administration of the exercise-conditioned plasma, denoting enhancement of the enzyme activity but impairment of its affinity for the substrate, respectively. These alterations are potential adaptations stimulated by the administered plasma pointing out that blood is an active fluid capable of regulating tissue homeostasis. Our findings suggest that K m adequately reflects in vivo modifications of skeletal muscle catalase and seems to surpass V max regarding its physiological relevance and biological interpretation. In conclusion, K m can be regarded as an in vivo-like biomarker that satisfactorily images the intracellular environment, as compared to V max that could be aptly parallelized with a biomarker that describes tissue oxidative stress in an in vitro manner. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

New Wistar Kyoto and spontaneously hypertensive rat transgenic models with ubiquitous expression of green fluorescent protein

Directory of Open Access Journals (Sweden)

Ana Isabel Garcia Diaz

2016-04-01

Full Text Available The Wistar Kyoto (WKY rat and the spontaneously hypertensive (SHR rat inbred strains are well-established models for human crescentic glomerulonephritis (CRGN and metabolic syndrome, respectively. Novel transgenic (Tg strains add research opportunities and increase scientific value to well-established rat models. We have created two novel Tg strains using Sleeping Beauty transposon germline transgenesis, ubiquitously expressing green fluorescent protein (GFP under the rat elongation factor 1 alpha (EF1a promoter on the WKY and SHR genetic backgrounds. The Sleeping Beauty system functioned with high transgenesis efficiency; 75% of new rats born after embryo microinjections were transgene positive. By ligation-mediated PCR, we located the genome integration sites, confirming no exonic disruption and defining a single or low copy number of the transgenes in the new WKY-GFP and SHR-GFP Tg lines. We report GFP-bright expression in embryos, tissues and organs in both lines and show preliminary in vitro and in vivo imaging data that demonstrate the utility of the new GFP-expressing lines for adoptive transfer, transplantation and fate mapping studies of CRGN, metabolic syndrome and other traits for which these strains have been extensively studied over the past four decades.

Arterial Retention of Remnant Lipoproteins Ex Vivo Is Increased in Insulin Resistance Because of Increased Arterial Biglycan and Production of Cholesterol-Rich Atherogenic Particles That Can Be Improved by Ezetimibe in the JCR:LA-cp Rat

Science.gov (United States)

Mangat, Rabban; Warnakula, Samantha; Borthwick, Faye; Hassanali, Zahra; Uwiera, Richard R.E.; Russell, James C.; Cheeseman, Christopher I.; Vine, Donna F.; Proctor, Spencer D

2012-01-01

Background Literature supports the “response-to-retention” hypothesis—that during insulin resistance, impaired metabolism of remnant lipoproteins can contribute to accelerated cardiovascular disease progression. We used the JCR:LA-cp rat model of metabolic syndrome (MetS) to determine the extent of arterial accumulation of intestinal-derived remnants ex vivo and potential mechanisms that contribute to exacerbated cholesterol deposition in insulin resistance. Methods and Results Arteries from control and MetS (insulin-resistant) JCR:LA-cp rats were perfused ex vivo with Cy5-labeled remnant lipoproteins, and their arterial retention was quantified by confocal microscopy. Arterial proteoglycans were isolated from control and MetS rats at 6, 12, and 32 weeks of age. There was a significant increase in the arterial retention of remnants and in associated cholesterol accumulation in MetS rats as compared to control rats. Mechanistic studies reveal that increased cholesterol deposition is a result of greater arterial biglycan content; longer glycosaminoglycans and increased production of cholesterol-rich intestinal-derived remnants, as compared to controls. Additionally, perfusion of vessels treated with ezetimibe, alone or in combination with simvastatin, with remnants isolated from the respective treatment group reduced ex vivo arterial retention of remnant-derived cholesterol ex vivo as compared to untreated controls. Conclusions Increased progression of atherosclerotic cardiovascular disease in MetS and type 2 diabetes mellitus might be explained in part by an increase in the arterial retention of cholesterol-rich remnants. Furthermore, ezetimibe alone or in combination treatment with simvastatin could be beneficial in ameliorating atherosclerotic cardiovascular disease in insulin resistance and MetS. PMID:23316299

In vivo and in vitro study of /sub 90/Sr in developing rat molar enamel

International Nuclear Information System (INIS)

White, B.A.; Deaton, T.G.; Bawden, J.W.

1980-01-01

The uptake patterns of /sub 90/Sr in developing rat molar enamel were studied in vivo and in vitro. Autoradiographic methods were used that preclude loss or translocation of tracers associated with water-soluble compounds in the sections. In eight-day-old rats injected with the tracer, /sub 90/Sr uptake in the enamel was significantly less than for dentin and bone, particularly at early sacrifice times. The uptake pattern of 90Sr was somewhat different from that previously observed for /sub 45/Ca. The in vitro experiments indicated that the viable intact enamel organ limits uptake of /sub 90/Sr by enamel in both the secretory and maturation phases of enamel formation

In vivo behavior of 111In-DTPA in rat and mouse after intra-ventricular administration

International Nuclear Information System (INIS)

Matsushima, Hiroaki; Kato, Makoto; Sugimura, Yukiharu; Hazue, Masaaki

1977-01-01

In vivo behavior of 111 In-DTPA in rat and mouse after intra-ventricular administration was studied. Thus, 50μCi and 35μCi of 111 In-DTPA was injected intraventricularly to rat and mouse respectively. At specific time intervals, the animals were sacrificed, then distribution in organs was determined by radioactivity counting and autoradiographic method. Urinary and fecal excretion were separately collected and excretion rates were estimated. Metabolites in urine of rat were examined with chromatography. A part of 111 In-DTPA injected intra-ventricularly to the animals migrated to subarachnoid space, then radioactivity in cerebrospinal fluid effused into blood with about 1 hr initial half-life. Blood clearance was also rapid, about 1 hr after administration the blood level reached maximum and then decreased showing an initial half-life of about 1 hr. The predominant excretion route in rat was urinary and about 90% and 5% of administered dose were excreted within 48 hr through urine and feces respectively. Judging from the Rf-value of radioactivity peak on chromatograms, 111 In-DTPA seems to be excreted without suffering any metabolic change. Concerning to the behavior of 111 In-DTPA in male and female rat, no difference was observed, and the distribution pattern of 111 In-DTPA in mouse was similar to that of rat. (auth.)

Oral Mucosa Model for Electrochemotherapy Treatment of Dog Mouth Cancer: Ex Vivo, In Silico, and In Vivo Experiments.

Science.gov (United States)

Suzuki, Daniela O H; Berkenbrock, José A; Frederico, Marisa J S; Silva, Fátima R M B; Rangel, Marcelo M M

2018-03-01

Electrochemotherapy (EQT) is a local cancer treatment well established to cutaneous and subcutaneous tumors. Electric fields are applied to biological tissue in order to improve membrane permeability for cytotoxic drugs. This phenomenon is called electroporation or electropermeabilization. Studies have reported that tissue conductivity is electric field dependent. Electroporation numerical models of biological tissues are essential in treatment planning. Tumors of the mouth are very common in dogs. Inadequate EQT treatment of oral tumor may be caused by significant anatomic variations between dogs and tumor position. Numerical models of oral mucosa and tumor allow the treatment planning and optimization of electrodes for each patient. In this work, oral mucosa conductivity during electroporation was characterized by measuring applied voltage and current of ex vivo rats. This electroporation model was used with a spontaneous canine oral melanoma. The model outcomes of oral tumor EQT is applied in different parts of the oral cavity including near bones and the hard palate. The numerical modeling for treatment planning will help the development of new electrodes and increase the EQT effectiveness. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Fumarase activity: an in vivo and in vitro biomarker for acute kidney injury

DEFF Research Database (Denmark)

Nielsen, Per Mose; Eldirdiri, Abubakr; Bertelsen, Lotte Bonde

2017-01-01

(2)] fumarate conversion to [1,4-C-13(2)] malate by fumarase has been proposed as a measure of necrosis in rat tumor models and in chemically induced AKI rats. Here we show that the degradation of cell membranes in connection with necrosis leads to elevated fumarase activity in plasma and urine and secondly...... that hyperpolarized [1,4-C-13(2)] malate production 24 h after reperfusion correlates with renal necrosis in a 40-min unilateral ischemic rat model. Fumarase activity screening on bio-fluids can detect injury severity, in bilateral as well as unilateral AKI models, differentiating moderate and severe AKI as well...... as short-and long-term AKI. Furthermore after verification of renal injury by bio-fluid analysis the precise injury location can be monitored by in vivo measurements of the fumarase activity non-invasively by hyperpolarized [1,4-C-13] fumarate MR imaging. The combined in vitro and in vivo biomarker of AKI...

Quantification of skeletal growth, modeling, and remodeling by in vivo micro computed tomography.

Science.gov (United States)

Altman, Allison R; Tseng, Wei-Ju; de Bakker, Chantal M J; Chandra, Abhishek; Lan, Shenghui; Huh, Beom Kang; Luo, Shiming; Leonard, Mary B; Qin, Ling; Liu, X Sherry

2015-12-01

In this study we established an image analysis scheme for the investigation of cortical and trabecular bone development during skeletal growth and tested this concept on in vivo μCT images of rats. To evaluate its efficacy, we applied the technique to young (1-month-old) and adult (3-month-old) rat tibiae with vehicle (Veh) or intermittent parathyroid hormone (PTH) treatment. By overlaying 2 sequential scans based on their distinct trabecular microarchitecture, we calculated the linear growth rate of young rats to be 0.31 mm/day at the proximal tibia. Due to rapid growth (3.7 mm in 12 days), the scanned bone region at day 12 had no overlap with the bone tissue scanned at day 0. Instead, the imaged bone region at day 12 represented newly generated bone tissue from the growth plate. The new bone of the PTH-treated rats had significantly greater trabecular bone volume fraction, number, and thickness than those of the Veh-treated rats, indicating PTH's anabolic effect on bone modeling. In contrast, the effect of PTH on adult rat trabecular bone was found to be caused by PTH's anabolic effect on bone remodeling. The cortical bone at the proximal tibia of young rats also thickened more in the PTH group (23%) than the Veh group (14%). This was primarily driven by endosteal bone formation and coalescence of trabecular bone into the cortex. This process can be visualized by aligning the local bone structural changes using image registration. As a result, the cortex after PTH treatment was 31% less porous, and had a 22% greater polar moment of inertia compared to the Veh group. Lastly, we monitored the longitudinal bone growth in adult rats by measuring the distance of bone flow away from the proximal tibial growth plate from 3 months to 19 months of age and discovered a total of 3.5mm growth in 16 months. It was demonstrated that this image analysis scheme can efficiently evaluate bone growth, bone modeling, and bone remodeling, and is ready to be translated into a

The ethanol metabolite acetaldehyde inhibits the induction of long-term potentiation in the rat dentate gyrus in vivo

Science.gov (United States)

Abe, Kazuho; Yamaguchi, Shinichi; Sugiura, Minoru; Saito, Hiroshi

1999-01-01

Ethanol has been reported to inhibit the induction of long-term potentiation (LTP) in the hippocampus. However, the correlation between the effects of ethanol in vivo and in vitro remained unclear. In addition, previous works have little considered the possibility that the effect of ethanol is mediated by its metabolites. To solve these problems, we investigated the effects of ethanol and acetaldehyde, the first metabolite in the metabolism of ethanol, on the induction of LTP at medial perforant path-granule cell synapses in the dentate gyrus of anaesthetized rats in vivo.Oral administration of 1 g kg−1 ethanol significantly inhibited the induction of LTP, confirming the effectiveness of ethanol in vivo.A lower dose of ethanol (0.5 g kg−1) failed to inhibit the induction of LTP in intact rats, but significantly inhibited LTP in rats treated with disulfiram, an inhibitor of aldehyde dehydrogenase, demonstrating that LTP is inhibited by acetaldehyde accumulation following ethanol administration.Intravenous injection of acetaldehyde (0.06 g kg−1) significantly inhibited the induction of LTP.The inhibitory effect of acetaldehyde on LTP induction was also observed when it was injected into the cerebroventricules, suggesting that acetaldehyde has a direct effect on the brain. The intracerebroventricular dose of acetaldehyde effective in inhibiting LTP induction (0.1–0.15 mg brain−1) was approximately 10 fold lower than that of ethanol (1.0–1.5 mg brain−1).It is possible that acetaldehyde is partly responsible for memory impairments induced by ethanol intoxication. PMID:10482910

Hypoglycemic depression of hepatic phagocytosis in vivo and in the in situ perfused rat liver.

Science.gov (United States)

Kober, P M; Filkins, J P

1981-01-01

Depression of the phagocytic function of the reticuloendothelial system (RES) during endotoxic hypoglycemia has been implicated in the pathogenesis of endotoxin shock. The present study evaluated the in vivo effects of hypoglycemia on RES function and assessed the effects of an vivo bout of hypoglycemia on phagocytosis in the in situ perfused rat liver. Hypoglycemia was produced in male Holtzman rats using either 1 U of regular insulin (RI) (ILETIN, Lilly) or 0.75 U of long-acting insulin (LAI) (85% LENTE/15% ULTRALENTE, Lilly). RES function was quantitated by intravascular clearance of 8 mg/100 gm body weight colloidal carbon (CC). Two hr after RI and 2.5 hr after LAI, the intravascular halftimes of CC clearance were 19 +/- 2 min (N = 22) and 18 +/- 1 min (N = 19), respectively, as compared to control, 11.3 +/- 0.4 min (N = 53, P less than 0.001). The corresponding plasma glucose (PG) levels were 95 +/- 2 mg/dl in control, 14.4 +/- 0.9 for the RI group, and 17 +/- 1 for LAI. Two hr after RI, livers were perfused for 10 min in situ with 50 mg/liter CC in saline 5% rat serum. PG for control liver donors were 90 +/- 3 mg/dl, while those for hypoglycemic liver donors were 15 +/- 2. CC uptake was decreased from 22 micrograms/min/gm liver in the control (+ serum, n = 19) to 11 +/- 2 in hypoglycemia livers (N = 6); no effect of serum on hypoglycemic depression of the RES was seen. There were no differences in flow rates in the 2 groups. These results indicate that hypoglycemia directly impairs RES function and that the in vivo depression of intravascular clearance is not related to either the presence or absence of serum factors or total hepatic blood flow. Thus, the characteristic hypoglycemia of endotoxin shock may contribute to RES depression and the lethal shock syndrome.

Magnetic resonance imaging of the normal and chronically injured adult rat spinal cord in vivo

International Nuclear Information System (INIS)

Guizar-Sahagun, G.; Rivera, F.; Babinski, E.; Berlanga, E.; Madrazo, M.; Franco-Bourland, R.; Grijalva, I.; Gonzalez, J.; Contreras, B.; Madrazo, I.

1994-01-01

We assessed the capacity of MRI to show and characterise the spinal cord (SC) in vivo in normal and chronically injured adult rats. In the chronically injured animals the SC was studied by MRI and histological examination. MRI was performed at 1.5 T, using gradient-echo and spin-echo (SE) sequences, the latter with and without gadolinium-DTPA (Gd-DTPA). Several positions were tried for good alignment and to diminish interference by respiratory movements. Images of the SC were obtained in sagittal, coronal, and axial planes. Normal SC was observed as a continuous intensity in both sequences, although contrast resolution was better using SE; it was not possible to differentiate the grey and white matter. Low signal was seen in the damaged area in chronically injured rats, which corresponded to cysts, trabeculae, mononuclear infiltrate, and fibroglial wall on histological examination. Gd-DTPA failed to enhance the SC in normal or chronically injured rats. It did, however, cause enhancement of the lesion after acute SC injury. (orig.)

Magnetic resonance imaging of the normal and chronically injured adult rat spinal cord in vivo

Energy Technology Data Exchange (ETDEWEB)

Guizar-Sahagun, G [Centro de Investigacion del Proyecto Camina, Mexico City (Mexico) Dept. of Clinical Research in Neurology and Neurosurgery, Hospital de Especialidades, Centro Medico Nacional Siglo XXI, Inst. Mexicano del Seguro Social, Mexico City (Mexico); Rivera, F [Centro de Investigacion del Proyecto Camina, Mexico City (Mexico); Babinski, E [Centro de Investigacion del Proyecto Camina, Mexico City (Mexico); Berlanga, E [Dept. of Magnetic Resonance Imaging, Hospital Angeles del Pedregal, Mexico City (Mexico); Madrazo, M [Dept. of Magnetic Resonance Imaging, Hospital Angeles del Pedregal, Mexico City (Mexico); Franco-Bourland, R [Centro de Investigacion del Proyecto Camina, Mexico City (Mexico) Dept. of Biochemistry, Inst. Nacional de la Nutricion, Mexico City (Mexico); Grijalva, I [Centro de Investigacion del Proyecto Camina, Mexico City (Mexico) Dept. of Clinical Research in Neurology and Neurosurgery, Hospital de Especialidades, Centro Medico Nacional Siglo

1994-08-01

We assessed the capacity of MRI to show and characterise the spinal cord (SC) in vivo in normal and chronically injured adult rats. In the chronically injured animals the SC was studied by MRI and histological examination. MRI was performed at 1.5 T, using gradient-echo and spin-echo (SE) sequences, the latter with and without gadolinium-DTPA (Gd-DTPA). Several positions were tried for good alignment and to diminish interference by respiratory movements. Images of the SC were obtained in sagittal, coronal, and axial planes. Normal SC was observed as a continuous intensity in both sequences, although contrast resolution was better using SE; it was not possible to differentiate the grey and white matter. Low signal was seen in the damaged area in chronically injured rats, which corresponded to cysts, trabeculae, mononuclear infiltrate, and fibroglial wall on histological examination. Gd-DTPA failed to enhance the SC in normal or chronically injured rats. It did, however, cause enhancement of the lesion after acute SC injury. (orig.)

Increased in vivo glucose utilization in 30-day-old obese Zucker rat: Role of white adipose tissue

International Nuclear Information System (INIS)

Krief, S.; Bazin, R.; Dupuy, F.; Lavau, M.

1988-01-01

In vivo whole-body glucose utilization and uptake in multiple individual tissues were investigated in conscious 30-day-old Zucker rats, which when obese are hyperphagic, hyperinsulinemic, and normoglycemic. Whole-body glucose metabolism (assessed by [3- 3 H]glucose) was 40% higher in obese (fa/fa) than in lean (Fa/fa) rats, suggesting that obese rats were quite responsive to their hyperinsulinemia. In obese compared with lean rats, tissue glucose uptake was increased by 15, 12, and 6 times in dorsal, inguinal, perigonadal white depots, respectively; multiplied by 2.5 in brown adipose tissue; increased by 50% in skin from inguinal region but not in that from cranial, thoracic, or dorsal area; and increased twofold in diaphragm but similar in heart in proximal intestine, and in total muscular mass of limbs. The data establish that in young obese rats the hypertrophied white adipose tissue was a major glucose-utilizing tissue whose capacity for glucose disposal compared with that of half the muscular mass. Adipose tissue could therefore play an important role in the homeostasis of glucose in obese rats in the face of their increased carbohydrate intake

Point correlation dimension can reveal functional changes caused by gap junction blockers in the 4-aminopyridine in vivo rat epilepsy model

Energy Technology Data Exchange (ETDEWEB)

Jardanhazy, Anett [Department of Neurology, University of Szeged, Semmelweis u. 6, Szeged H-6725 (Hungary); Molnar, Mark [Department of Psychophysiology, Institute for Psychology of the Hungarian Academy of Sciences, P.O. Box 398, Budapest H-1394 (Hungary)], E-mail: molnar@cogpsyphy.hu; Jardanhazy, Tamas [Department of Neurology, University of Szeged, Semmelweis u. 6, Szeged H-6725 (Hungary)], E-mail: jt@nepsy.szote.u-szeged.hu

2009-04-15

The contribution of gap junction (GJ) blockers to seizure initiation was reexamined by means of an analysis on nonlinear dynamics with point correlation dimension (PD2i) at as well as around the primary focus, and mirror focus in an already active 4-aminopyridine-induced in vivo epilepsy model. From the data base of the ECoGs of anesthetized adult rats treated with quinine, a selective blocker of Cx36, and in combination with an additional broad-spectrum GJ blocker, carbenoxolone, 14 cases of each condition were reexamined with a stationarity insensitive nonlinear PD2i method. The blockade of the Cx36 channels decreased the usual drop of the point correlation dimension at the beginning of the seizures, and this was enhanced by the additional use of the global blocker carbenoxolone. The so-called characteristic DC shift just prior to seizure onset denotes a low dimensional seizure event and the recognizable seizures display very variable, rapidly changing dynamics, as revealed by the PD2i analysis. This nonlinear PD2i analysis demonstrated that the different GJ blockers in the already active epileptic model helped seizure initiation, but exerted inhibitory effects on the seizure onset itself, acting differently on the local components of the network organization generating seizure discharges, possibly changing the coupling strengths and time delays in the GJ-s.

Point correlation dimension can reveal functional changes caused by gap junction blockers in the 4-aminopyridine in vivo rat epilepsy model

International Nuclear Information System (INIS)

Jardanhazy, Anett; Molnar, Mark; Jardanhazy, Tamas

2009-01-01

The contribution of gap junction (GJ) blockers to seizure initiation was reexamined by means of an analysis on nonlinear dynamics with point correlation dimension (PD2i) at as well as around the primary focus, and mirror focus in an already active 4-aminopyridine-induced in vivo epilepsy model. From the data base of the ECoGs of anesthetized adult rats treated with quinine, a selective blocker of Cx36, and in combination with an additional broad-spectrum GJ blocker, carbenoxolone, 14 cases of each condition were reexamined with a stationarity insensitive nonlinear PD2i method. The blockade of the Cx36 channels decreased the usual drop of the point correlation dimension at the beginning of the seizures, and this was enhanced by the additional use of the global blocker carbenoxolone. The so-called characteristic DC shift just prior to seizure onset denotes a low dimensional seizure event and the recognizable seizures display very variable, rapidly changing dynamics, as revealed by the PD2i analysis. This nonlinear PD2i analysis demonstrated that the different GJ blockers in the already active epileptic model helped seizure initiation, but exerted inhibitory effects on the seizure onset itself, acting differently on the local components of the network organization generating seizure discharges, possibly changing the coupling strengths and time delays in the GJ-s.

Gadolinium-enhanced 7.0 T magnetic resonance imaging assessment of the aqueous inflow in rat eyes in vivo.

Science.gov (United States)

Li, Lu; Yuan, Yuxiang; Chen, Liwen; Li, Mu; Ji, Pingting; Gong, Jieling; Zhao, Yin; Zhang, Hong

2017-09-01

The goal of this study was to calculate the anterior chamber volume and assess aqueous inflow in rat eyes in vivo, under anesthetic condition. Gadolinium-contrast agent (Gd-DTPA, 234.5 mg/ml) was administered to Sprague-Dawley rat eyes via anterior chamber injection or instillation of 234.5 or 117.25 mg/ml Gd-DTPA in 0.2% azone as eye drops, and changes of Gd signal visualized by 7.0 T magnetic resonance imaging (MRI). The safety of local application of Gd-DTPA and azone were performed after MRI scanning. The anterior chamber injection of Gd-DTPA (234.5 mg/ml) group was used for anterior chamber volume and aqueous inflow calculating. Serial changes in Gd-DTPA relative concentration in the anterior chamber was determined based on the initial Gd signal gray values and the initial relative concentration of Gd-DTPA after anterior chamber Gd-DTPA injection. The mean aqueous inflow in rat eyes in vivo was assessed based on changes in Gd-DTPA relative concentration and the anterior chamber volume. Eye drops of Gd-DTPA (234.5 mg/ml) in 0.2% azone readily allowed safe assessment of the aqueous inflow by 7.0 T MRI. Under anesthetic condition in vivo, the mean anterior chamber volume (ACV) in rats was 8493.6 ± 657.4 μm 3 , no differences were observed in the aqueous inflow measured by topical instillation of 234.5 mg/ml Gd-DTPA in 0.2% azone (0.182 ± 0.011 μl/min) between that measured by anterior chamber injection (0.165 ± 0.041 μl/min, P > 0.05), Timolol reduced aqueous inflow to 0.124 ± 0.020 μl/min (P DTPA can be assessed by the variability of relative concentration of Gd-DTPA in anterior chamber and ACV in vivo, under anesthetic condition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optogenetic delay of status epilepticus onset in an in vivo rodent epilepsy model.

Directory of Open Access Journals (Sweden)

Inna Sukhotinsky

Full Text Available Epilepsy is a devastating disease, currently treated with medications, surgery or electrical stimulation. None of these approaches is totally effective and our ability to control seizures remains limited and complicated by frequent side effects. The emerging revolutionary technique of optogenetics enables manipulation of the activity of specific neuronal populations in vivo with exquisite spatiotemporal resolution using light. We used optogenetic approaches to test the role of hippocampal excitatory neurons in the lithium-pilocarpine model of acute elicited seizures in awake behaving rats. Hippocampal pyramidal neurons were transduced in vivo with a virus carrying an enhanced halorhodopsin (eNpHR, a yellow light activated chloride pump, and acute seizure progression was then monitored behaviorally and electrophysiologically in the presence and absence of illumination delivered via an optical fiber. Inhibition of those neurons with illumination prior to seizure onset significantly delayed electrographic and behavioral initiation of status epilepticus, and altered the dynamics of ictal activity development. These results reveal an essential role of hippocampal excitatory neurons in this model of ictogenesis and illustrate the power of optogenetic approaches for elucidation of seizure mechanisms. This early success in controlling seizures also suggests future therapeutic avenues.

A study of the uptake and biodistribution of nano-titanium dioxide using in vitro and in vivo models of oral intake

International Nuclear Information System (INIS)

MacNicoll, Alan; Kelly, Mick; Aksoy, Hatice; Kramer, Evelien; Bouwmeester, Hans; Chaudhry, Qasim

2015-01-01

Certain food additives may contain a sizeable fraction of particles in the nanoscale. However, little is known about the fate, behaviour and toxicological effects of orally-ingested nanoparticles. This study investigated the uptake and biodistribution of nano- and larger-sized titanium dioxide (TiO 2 ) using an in vitro model of gut epithelium and in vivo in rat. The results of the in vivo study showed that oral administration of 5 mg/kg body weight of TiO 2 nano- or larger particles did not lead to any significant translocation of TiO 2 (measured as titanium) either to blood, urine or to various organs in rat at any of the time intervals studied over a 96 h post-administration period. Different methods used for dispersing particles did not affect the uptake, and orally administered TiO 2 was found excreted in the faeces over a period of time. The in vitro study provided further evidence for the lack of translocation of TiO 2 across the gut epithelium model. The overall evidence from both in vivo and in vitro studies did not support that oral ingestion of nano- or larger particles of TiO 2 via food would result in any significant internal exposure of the consumer to the nanoparticles. The dietary TiO 2 nanoparticles are likely to be excreted in the faeces

A study of the uptake and biodistribution of nano-titanium dioxide using in vitro and in vivo models of oral intake

Science.gov (United States)

MacNicoll, Alan; Kelly, Mick; Aksoy, Hatice; Kramer, Evelien; Bouwmeester, Hans; Chaudhry, Qasim

2015-02-01

Certain food additives may contain a sizeable fraction of particles in the nanoscale. However, little is known about the fate, behaviour and toxicological effects of orally-ingested nanoparticles. This study investigated the uptake and biodistribution of nano- and larger-sized titanium dioxide (TiO2) using an in vitro model of gut epithelium and in vivo in rat. The results of the in vivo study showed that oral administration of 5 mg/kg body weight of TiO2 nano- or larger particles did not lead to any significant translocation of TiO2 (measured as titanium) either to blood, urine or to various organs in rat at any of the time intervals studied over a 96 h post-administration period. Different methods used for dispersing particles did not affect the uptake, and orally administered TiO2 was found excreted in the faeces over a period of time. The in vitro study provided further evidence for the lack of translocation of TiO2 across the gut epithelium model. The overall evidence from both in vivo and in vitro studies did not support that oral ingestion of nano- or larger particles of TiO2 via food would result in any significant internal exposure of the consumer to the nanoparticles. The dietary TiO2 nanoparticles are likely to be excreted in the faeces.

In Vivo Respiratory-Gated Micro-CT Imaging in Small-Animal Oncology Models

Directory of Open Access Journals (Sweden)

Dawn Cavanaugh

2004-01-01

Full Text Available Micro-computed tomography (micro-CT is becoming an accepted research tool for the noninvasive examination of laboratory animals such as mice and rats, but to date, in vivo scanning has largely been limited to the evaluation of skeletal tissues. We use a commercially available micro-CT device to perform respiratory gated in vivo acquisitions suitable for thoracic imaging. The instrument is described, along with the scan protocol and animal preparation techniques. Preliminary results confirm that lung tumors as small as 1 mm in diameter are visible in vivo with these methods. Radiation dose was evaluated using several approaches, and was found to be approximately 0.15 Gy for this respiratory-gated micro-CT imaging protocol. The combination of high-resolution CT imaging and respiratory-gated acquisitions appears well-suited to serial in vivo scanning.

The CNTF-derived peptide mimetic Cintrofin attenuates spatial-learning deficits in a rat post-status epilepticus model

DEFF Research Database (Denmark)

Russmann, Vera; Seeger, Natalie; Zellinger, Christina

2013-01-01

Ciliary neurotrophic growth factor is considered a potential therapeutic agent for central nervous system diseases. We report first in vivo data of the ciliary neurotrophic growth factor peptide mimetic Cintrofin in a rat post-status epilepticus model. Cintrofin prevented long-term alterations...... in the number of doublecortin-positive neuronal progenitor cells and attenuated the persistence of basal dendrites. In contrast, Cintrofin did neither affect acute status epilepticus-associated alterations in hippocampal cell proliferation and neurogenesis nor reveal any relevant effect on seizure activity....... Whereas status epilepticus caused a significant disturbance in spatial learning in reversed peptide-treated rats, the performance of Cintrofin-treated rats did not differ from controls. The study confirms that Cintrofin comprises an active sequence mimicking effects of its parent molecule. While the data...

Organotypic lung culture: A new model for studying ischemia and ex vivo perfusion in lung transplantation.

Science.gov (United States)

Baste, Jean-Marc; Gay, Arnaud; Smail, Hassiba; Noël, Romain; Bubenheim, Michael; Begueret, Hugues; Morin, Jean-Paul; Litzler, Pierre-Yves

2015-01-01

Donors after cardiac death (DCD) in lung transplantation is considered as a solution for organ shortage. However, it is characterized by warm ischemic period, which could be involved in severe Ischemia-Reperfusion lesion (IR) with early graft dysfunction. We describe a new hybrid model combining in vivo ischemia followed by in vitro reoxygenation using organ-specific culture. A hybrid model using in vivo ischemic period followed by in vitro lung slice reoxygenation was set up in rat to mimic DCD in lung transplantation with in vitro perfusion. Different markers (bioenergetics, oxidant stress assays, and histology) were measured to evaluate the viability of lung tissue after different ischemic times (I-0, I-1, I-2, I-4, I-15 hours) and reoxygenation times (R-0, R-1, R-4, R-24 hours). No differences were found in cell viability, ATP concentrations, extracellular LDH assays or histology, demonstrating extensive viability of up to 4 hours in lung tissue warm ischemia. We found oxidative stress mainly during the ischemic period with no burst at reoxygenation. Cytosolic anti-oxidant system was involved first (I-0,I-1,I-2) followed by mitochondrial anti-oxidant system for extensive ischemia (I-4). Histological features showed differences in this model of ischemia-reoxygenation between bronchial epithelium and lung parenchymal cells, with epithelium regeneration after 2 hours of warm ischemia and 24 hours of perfusion. The results of our hybrid model experiment suggest extensive lung viability of up to 4 hours ischemia. Our model could be an interesting tool to evaluate ex vivo reconditioning techniques after different in vivo lung insults.

Olesoxime (cholest-4-en-3-one, oxime): Analgesic and neuroprotective effects in a rat model of painful peripheral neuropathy produced by the chemotherapeutic agent, paclitaxel

OpenAIRE

Xiao, Wen Hua; Zheng, Felix Y.; Bennett, Gary J.; Bordet, Thierry; Pruss, Rebecca M.

2009-01-01

Olesoxime is a small cholesterol-like molecule that was discovered in a screening program aimed at finding treatment for amyotrophic lateral sclerosis and other diseases where motor neurons degenerate. In addition to its neuroprotective and pro-regenerative effects on motor neurons in vitro and in vivo, it has been shown to have analgesic effects in rat models of painful peripheral neuropathy due to vincristine and diabetes. We used a rat model of painful peripheral neuropathy produced by the...

In vivo Evaluation of Amoxicillin Trihydrate and Clarithromycin ...

African Journals Online (AJOL)

In vivo clearance efficacy of the microspheres was evaluated in a Wistar rat model after induction of H. pylori infection. Amoxicillin and clarithromycin-loaded microspheres were administered twice daily for three days. H. Pylori clearance was evaluated by assessing colony count. Results: Treatment with plain drug solution ...

Evaluation of [{sup 11}C]rofecoxib as PET tracer for cyclooxygenase 2 overexpression in rat models of inflammation

Energy Technology Data Exchange (ETDEWEB)

Vries, Erik F.J. de [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen (Netherlands)], E-mail: e.f.j.de.vries@ngmb.umcg.nl; Doorduin, Janine; Dierckx, Rudi A.; Waarde, Aren van [Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen (Netherlands)

2008-01-15

Background: Overexpression of cyclooxygenase type 2 (COX-2) is triggered by inflammatory stimuli, but it also plays a prominent role in the initiation and progression of various diseases. This study aims to investigate [{sup 11}C]rofecoxib as a positron emission tomography (PET) tracer for COX-2 expression. Methods: [{sup 11}C]Rofecoxib was prepared by methylation of its sulphinate precursor. Regional brain distribution and specific binding of [{sup 11}C]rofecoxib in healthy rats was studied by ex vivo biodistribution and autoradiography. Regional brain distribution and PET imaging studies were also performed on rats with severe encephalitis, caused by nasal infection with herpes simplex virus (HSV). Finally, ex vivo biodistribution and blocking studies were carried in rats with a sterile inflammation, induced by intramuscular turpentine injection. Results: [{sup 11}C]rofecoxib brain uptake in control animals corresponded with the known distribution of COX-2. Pretreatment with NS398 significantly reduced tracer uptake in the cingulate/frontopolar cortex, whereas the reduction in hippocampus approached significance. Ex vivo autoradiography also revealed preferential tracer uptake in hippocampus and cortical areas that could be blocked by NS398. In HSV-infected animals, [{sup 11}C]rofecoxib uptake was moderately increased in all brain regions, but it could not be blocked with indomethacin. Yet, some PET images revealed increased tracer uptake in brain areas with microglia activation. In turpentine-injected animals, [{sup 11}C]rofecoxib uptake in inflamed muscle was not higher than in control muscle and could not be blocked with NS398. Indomethacin caused a slight reduction in muscle uptake. Conclusions: Despite the apparent correlation between [{sup 11}C]rofecoxib uptake and COX-2 distribution in healthy rats, [{sup 11}C]rofecoxib could not unambiguously detect COX-2 overexpression in two rat models of inflammation.

Pituitary and brain D2 receptor density measured in vitro and in vivo in EEDQ treated male rats

International Nuclear Information System (INIS)

Ekman, A.; Eriksson, E.

1991-01-01

The effect of the alkylating compound N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) on dopamine D2 receptor density in rat pituitary and brain was measured using in vitro and in vivo radioligand binding techniques. In the in vitro radioligand binding experiments EEDQ was found to reduce the density (B max ) of [ 3 H]-spiperone binding sites in the striatum by 86% while in the pituitary the corresponding decrease was only 37%. The affinity (K D ) of the remaining striatal and pituitary D2 receptors was not different in EEDQ treated animals as compared to controls. When D2 receptor density was measured in vivo the effect of EEDQ was less pronounced. Thus, in rats given EEDQ the specific binding of either of the two D2 ligands [ 3 H]-raclopride or [ 3 H]-spiperone in striatum and in the limbic forebrain was reduced by 45-62%; moreover, no significant decrease in pituitary D2 receptor density was observed. The data are discussed in relation to the finding that the same dose of EEDQ that failed to influence pituitary D2 receptor density as measured in vivo effectively antagonizes the prolactin decreasing effect of the partial D2 agonist (-)-3-(3-hydroxyphenyl)-N-n-propyl-piperidine [(-)-3-PPP

In vivo cellular uptake of glutamate is impaired in the rat hippocampus during and after transient cerebral ischemia

DEFF Research Database (Denmark)

Bruhn, T; Christensen, Thomas; Diemer, Nils Henrik

2001-01-01

Using microdialysis in CA1 of the rat hippocampus, we studied the effect of transient cerebral ischemia on in vivo uptake and on extracellular levels of glutamate during, and at different time points after ischemia. (3)H-D-aspartate (test substance), and (14)C-mannitol (reference substance), were...

A Rat Model for Muscle Regeneration in the Soft Palate

Science.gov (United States)

Carvajal Monroy, Paola L.; Grefte, Sander; Kuijpers-Jagtman, Anne M.; Helmich, Maria P. A. C.; Ulrich, Dietmar J. O.; Von den Hoff, Johannes W.; Wagener, Frank A. D. T. G.

2013-01-01

Background Children with a cleft in the soft palate have difficulties with speech, swallowing, and sucking. Despite successful surgical repositioning of the muscles, optimal function is often not achieved. Scar formation and defective regeneration may hamper the functional recovery of the muscles after cleft palate repair. Therefore, the aim of this study is to investigate the anatomy and histology of the soft palate in rats, and to establish an in vivo model for muscle regeneration after surgical injury. Methods Fourteen adult male Sprague Dawley rats were divided into four groups. Groups 1 (n = 4) and 2 (n = 2) were used to investigate the anatomy and histology of the soft palate, respectively. Group 3 (n = 6) was used for surgical wounding of the soft palate, and group 4 (n = 2) was used as unwounded control group. The wounds (1 mm) were evaluated by (immuno)histochemistry (AZAN staining, Pax7, MyoD, MyoG, MyHC, and ASMA) after 7 days. Results The present study shows that the anatomy and histology of the soft palate muscles of the rat is largely comparable with that in humans. All wounds showed clinical evidence of healing after 7 days. AZAN staining demonstrated extensive collagen deposition in the wound area, and initial regeneration of muscle fibers and salivary glands. Proliferating and differentiating satellite cells were identified in the wound area by antibody staining. Conclusions This model is the first, suitable for studying muscle regeneration in the rat soft palate, and allows the development of novel adjuvant strategies to promote muscle regeneration after cleft palate surgery. PMID:23554995

In vivo binding and autoradiographic imaging of (+)-3-[125I]Iodo-MK-801 to the NMDA receptor-channel complex in rat brain

International Nuclear Information System (INIS)

Gibson, R.E.; Burns, H.D.; Thorpe, H.H.; Waisi Eng; Ransom, R.; Solomon, H.

1992-01-01

Radioiodinated (+)-3-Iodo-MK-801 is a high affinity radioligand for the N-methyl-D-aspartate (NMDA) receptor-channel complex. We have demonstrated in vivo localization in the CNS of rat which is stereoselective and blocked by coinjection of unlabeled MK-801. Autoradiography indicates localization in vivo which is in concordance with in vitro autoradiographic studies. These results indicate that radioiodinated (+)-3-Iodo-MK-801 is a useful probe for in vitro and in vivo autoradiographic studies and suggest that radioligands for the NMDA receptor may be developed which will provide in vivo images of receptor distribution in man. (author)

Sagunja-Tang Improves Lipid Related Disease in a Postmenopausal Rat Model and HepG2 Cells

Directory of Open Access Journals (Sweden)

Hiroe Go

2015-01-01

Full Text Available The present study was conducted to investigate the effect of Sagunja-tang on the lipid related disease in a rat model of menopausal hyperlipidemia and lipid accumulation in methyl-β-cyclodextrin-induced HepG2 cells. In in vivo study using menopausal hyperlipidemia rats, Sagunja-tang reduced retroperitoneal and perirenal fat, serum lipids, atherogenic index, cardiac risk factor, media thickness, and nonalcoholic steatohepatitis score, when compared to menopausal hyperlipidemia control rats. In HepG2 cells, Sagunja-tang significantly decreased the lipid accumulation, total cholesterol levels, and low-density/very-low-density lipoprotein levels. Moreover, Sagunja-tang reversed the methyl-β-cyclodextrin-induced decrease in the protein levels of critical molecule involved in cholesterol synthesis, sterol regulatory element binding protein-2, and low-density lipoprotein receptor and inhibited protein levels of 3-hydroxy-3-methylglutaryl coenzyme A reductase as well as activity. Phosphorylation level of AMP-activated protein kinase was stimulated by Sagunja-tang. These results suggest that Sagunja-tang has effect on inhibiting hepatic lipid accumulation through regulation of cholesterol synthesis and AMPK activity in vitro. These observations support the idea that Sagunja-tang is bioavailable both in vivo and in vitro and could be developed as a preventive and therapeutic agent of hyperlipidemia in postmenopausal females.

Ketone-body utilization and lipid synthesis by developing rat brain—a comparison between in vivo and in vitro experiments

NARCIS (Netherlands)

Klein, W.; Lopes-Cardozo, M.

1984-01-01

The distribution of ketone bodies between oxidation and lipid synthesis was analysed in homogenates of developing rat brain. The capacity for lipid synthesis of homogenized or minced brain preparations was compared with rates of lipid synthesis in vivo, assessed by incorporation of ³H from

In vivo determination of body composition of rats using magnetic resonance imaging.

Science.gov (United States)

Tang, H; Vasselli, J; Wu, E; Gallagher, D

2000-05-01

Magnetic resonance imaging (MRI) has potential as an instrument to measure body composition because it can discriminate various soft tissues in vivo. These soft tissues include adipose tissue, muscle, organs, and brain. We report on preliminary studies using a 4.2-tesla MRI for measuring body composition in the mouse and rat. We employed image segmentation methods that include an image correction method, a necessary requirement when the images are taken in the presence of nonuniform radio-frequency (RF) coil response. The software for 3-D data segmentation, quantification, correction, image manipulation, and visualization has been developed as a research tool. This method currently is being validated.

Comparing the cardiovascular therapeutic indices of glycopyrronium and tiotropium in an integrated rat pharmacokinetic, pharmacodynamic and safety model

International Nuclear Information System (INIS)

Trifilieff, Alexandre; Ethell, Brian T.; Sykes, David A.; Watson, Kenny J.; Collingwood, Steve; Charlton, Steven J.; Kent, Toby C.

2015-01-01

Long acting inhaled muscarinic receptor antagonists, such as tiotropium, are widely used as bronchodilator therapy for chronic obstructive pulmonary disease (COPD). Although this class of compounds is generally considered to be safe and well tolerated in COPD patients the cardiovascular safety of tiotropium has recently been questioned. We describe a rat in vivo model that allows the concurrent assessment of muscarinic antagonist potency, bronchodilator efficacy and a potential for side effects, and we use this model to compare tiotropium with NVA237 (glycopyrronium bromide), a recently approved inhaled muscarinic antagonist for COPD. Anaesthetized Brown Norway rats were dosed intratracheally at 1 or 6 h prior to receiving increasing doses of intravenous methacholine. Changes in airway resistance and cardiovascular function were recorded and therapeutic indices were calculated against the ED 50 values for the inhibition of methacholine-induced bronchoconstriction. At both time points studied, greater therapeutic indices for hypotension and bradycardia were observed with glycopyrronium (19.5 and 28.5 fold at 1 h; > 200 fold at 6 h) than with tiotropium (1.5 and 4.2 fold at 1 h; 4.6 and 5.5 fold at 6 h). Pharmacokinetic, protein plasma binding and rat muscarinic receptor binding properties for both compounds were determined and used to generate an integrated model of systemic M 2 muscarinic receptor occupancy, which predicted significantly higher M 2 receptor blockade at ED 50 doses with tiotropium than with glycopyrronium. In our preclinical model there was an improved safety profile for glycopyrronium when compared with tiotropium. - Highlights: • We use an in vivo rat model to study CV safety of inhaled muscarinic antagonists. • We integrate protein and receptor binding and PK of tiotropium and glycopyrrolate. • At ED 50 doses for bronchoprotection we model systemic M 2 receptor occupancy. • Glycopyrrolate demonstrates lower M 2 occupancy at

Comparing the cardiovascular therapeutic indices of glycopyrronium and tiotropium in an integrated rat pharmacokinetic, pharmacodynamic and safety model

Energy Technology Data Exchange (ETDEWEB)

Trifilieff, Alexandre; Ethell, Brian T. [Respiratory Disease Area, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex RH12 5AB (United Kingdom); Sykes, David A. [Respiratory Disease Area, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex RH12 5AB (United Kingdom); School of Life Sciences, Queen' s Medical Centre, University of Nottingham, Nottingham, NG7 2UH (United Kingdom); Watson, Kenny J.; Collingwood, Steve [Respiratory Disease Area, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex RH12 5AB (United Kingdom); Charlton, Steven J. [Respiratory Disease Area, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex RH12 5AB (United Kingdom); School of Life Sciences, Queen' s Medical Centre, University of Nottingham, Nottingham, NG7 2UH (United Kingdom); Kent, Toby C., E-mail: tobykent@me.com [Respiratory Disease Area, Novartis Institutes for Biomedical Research, Wimblehurst Road, Horsham, West Sussex RH12 5AB (United Kingdom)

2015-08-15

Long acting inhaled muscarinic receptor antagonists, such as tiotropium, are widely used as bronchodilator therapy for chronic obstructive pulmonary disease (COPD). Although this class of compounds is generally considered to be safe and well tolerated in COPD patients the cardiovascular safety of tiotropium has recently been questioned. We describe a rat in vivo model that allows the concurrent assessment of muscarinic antagonist potency, bronchodilator efficacy and a potential for side effects, and we use this model to compare tiotropium with NVA237 (glycopyrronium bromide), a recently approved inhaled muscarinic antagonist for COPD. Anaesthetized Brown Norway rats were dosed intratracheally at 1 or 6 h prior to receiving increasing doses of intravenous methacholine. Changes in airway resistance and cardiovascular function were recorded and therapeutic indices were calculated against the ED{sub 50} values for the inhibition of methacholine-induced bronchoconstriction. At both time points studied, greater therapeutic indices for hypotension and bradycardia were observed with glycopyrronium (19.5 and 28.5 fold at 1 h; > 200 fold at 6 h) than with tiotropium (1.5 and 4.2 fold at 1 h; 4.6 and 5.5 fold at 6 h). Pharmacokinetic, protein plasma binding and rat muscarinic receptor binding properties for both compounds were determined and used to generate an integrated model of systemic M{sub 2} muscarinic receptor occupancy, which predicted significantly higher M{sub 2} receptor blockade at ED{sub 50} doses with tiotropium than with glycopyrronium. In our preclinical model there was an improved safety profile for glycopyrronium when compared with tiotropium. - Highlights: • We use an in vivo rat model to study CV safety of inhaled muscarinic antagonists. • We integrate protein and receptor binding and PK of tiotropium and glycopyrrolate. • At ED{sub 50} doses for bronchoprotection we model systemic M{sub 2} receptor occupancy. • Glycopyrrolate demonstrates lower M

[Establishment of rat model of psychical erectile dysfunction].

Science.gov (United States)

Wang, Qiu-lin; Wang, Shu-ren; Duan, Jin

2006-01-01

To set up a method of establishing the animal model of psychical erectile dysfunction with emotional stress. All thirty-six male rats with normal sexual function were divided into three groups, i. e. normal group, model group and demasculinized group randomly according to their weights. The rats in the model group were suspended upside down in midair over the water and irritated repeatedly. Two weeks later, the sexual abilities of all rats, i. e. the times of mounting and intromitting the estrus female rats, the latent period of mounting, intromission and ejaculation, were recorded, and the number of rats that had sexual activities was also counted. And the hemorheology indices of the rats were measured. Compared with the normal rats, the latency of mounting [(152.5 +/- 24.6) s vs (42.4 +/- 9.6) s] and intromission [(437.0 +/- 67.7) s vs (130.8 +/- 39.1) s] of the model rats were longer (P 0.05). The hemorheology indices, e. g. blood viscosity, hematocrit (Hct) and red cell aggregation (RCA), of the model rats was significant higher than that of the normal and demasculinized rats (P erectile dysfunction can be made ideally with psychical stress.

A comparison of in vivo and in vitro methods for determining availability of iron from meals

International Nuclear Information System (INIS)

Schricker, B.R.; Miller, D.D.; Rasmussen, R.R.; Van Campen, D.

1981-01-01

A comparison is made between in vitro and human and rat in vivo methods for estimating food iron availability. Complex meals formulated to replicate meals used by Cook and Monsen (Am J Clin Nutr 1976;29:859) in human iron availability trials were used in the comparison. The meals were prepared by substituting pork, fish, cheese, egg, liver, or chicken for beef in two basic test meals and were evaluated for iron availability using in vitro and rat in vivo methods. When the criterion for comparison was the ability to show statistically significant differences between iron availability in the various meals, there was substantial agreement between the in vitro and human in vivo methods. There was less agreement between the human in vivo and the rat in vivo and between the in vivo and the rat in vivo and between the in vitro and the rat in vivo methods. Correlation analysis indicated significant agreement between in vitro and human in vivo methods. Correlation between the rat in vivo and human in vivo methods were also significant but correlations between the in vitro and rat in vivo methods were less significant and, in some cases, not significant. The comparison supports the contention that the in vitro method allows a rapid, inexpensive, and accurate estimation of nonheme iron availability in complex meals

In vivo assay for conversion of testosterone to dihydrotestosterone by rat prostatic steroid 5 alpha-reductase and comparison of two inhibitors

International Nuclear Information System (INIS)

Toomey, R.E.; Goode, R.L.; Petrow, V.; Neubauer, B.L.

1991-01-01

An in vivo assay for steroid 5 alpha-reductase in rat ventral prostate has been developed and used to compare the inhibitory activity of N,N-diethyl-4-methyl-3-oxo-4-aza-5 alpha-androstane-17 beta-carboxamide (4-MA) and 6-methylene-4-pregnene-3,20-dione (LY207320). Immature rats (70-80 g) received test compounds 30 min prior to s.c. injection of [3H]-T. The rats were sacrificed 30 min later and the ventral prostates were analyzed for [3H]-T metabolites. Intraprostatic [3H]-T and [3H]-DHT reached peak levels within 5 min after injection of [3H]-T and declined to about 25% of peak levels after 2 hr. 4-MA was a very potent inhibitor of [3H]-DHT formation with an estimated IC50 of 0.2 mg/kg. LY207320, an inhibitor of 5 alpha-reductase in vitro, was weakly active in vivo and did not achieve greater than 45% inhibition at high doses (greater than 200 mg/kg, s.c.). Tissue uptake of [3H]-T was also inhibited by LY207320, which may contribute to its inhibitory activity on accessory sex organ growth in the rat

In vivo genotoxic effects of dietary heme iron on rat colon mucosa and ex vivo effects on colon cells monitored by an optimized alkaline comet assay.

Directory of Open Access Journals (Sweden)

Océane, C Martin

2015-04-01

In conclusion, our results offer a suitable protocol to evaluate genotoxicity on in vivo cryopreserved colon mucosa and on in vitro murine colonic cells, with a middle throughput capacity. This protocol confirms the increase of genotoxicity in rat colon mucosa after an heme-iron diet. Moreover, this protocol enables the demonstration that aldehydes from heme-induced lipoperoxidation are responsible for this increase of genotoxicity.

In vivo transgenic expression of collybistin in neurons of the rat cerebral cortex.

Science.gov (United States)

Fekete, Christopher D; Goz, Roman U; Dinallo, Sean; Miralles, Celia P; Chiou, Tzu-Ting; Bear, John; Fiondella, Christopher G; LoTurco, Joseph J; De Blas, Angel L

2017-04-01

Collybistin (CB) is a guanine nucleotide exchange factor selectively localized to γ-aminobutyric acid (GABA)ergic and glycinergic postsynapses. Active CB interacts with gephyrin, inducing the submembranous clustering and the postsynaptic accumulation of gephyrin, which is a scaffold protein that recruits GABA A receptors (GABA A Rs) at the postsynapse. CB is expressed with or without a src homology 3 (SH3) domain. We have previously reported the effects on GABAergic synapses of the acute overexpression of CB SH3- or CB SH3+ in cultured hippocampal (HP) neurons. In the present communication, we are studying the effects on GABAergic synapses after chronic in vivo transgenic expression of CB2 SH3- or CB2 SH3+ in neurons of the adult rat cerebral cortex. The embryonic precursors of these cortical neurons were in utero electroporated with CB SH3- or CB SH3+ DNAs, migrated to the appropriate cortical layer, and became integrated in cortical circuits. The results show that: 1) the strength of inhibitory synapses in vivo can be enhanced by increasing the expression of CB in neurons; and 2) there are significant differences in the results between in vivo and in culture studies. J. Comp. Neurol. 525:1291-1311, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

In vivo microcomputed tomography evaluation of rat alveolar bone and root resorption during orthodontic tooth movement.

Science.gov (United States)

Ru, Nan; Liu, Sean Shih-Yao; Zhuang, Li; Li, Song; Bai, Yuxing

2013-05-01

To observe the real-time microarchitecture changes of the alveolar bone and root resorption during orthodontic treatment. A 10 g force was delivered to move the maxillary left first molars mesially in twenty 10-week-old rats for 14 days. The first molar and adjacent alveolar bone were scanned using in vivo microcomputed tomography at the following time points: days 0, 3, 7, and 14. Microarchitecture parameters, including bone volume fraction, structure model index, trabecular thickness, trabecular number, and trabecular separation of alveolar bone, were measured on the compression and tension side. The total root volume was measured, and the resorption crater volume at each time point was calculated. Univariate repeated measures analysis of variance with Bonferroni corrections were performed to compare the differences in each parameter between time points with significance level at P Root resorption volume of the mesial root increased significantly on day 7 of orthodontic loading. Real-time root and bone resorption during orthodontic movement can be observed in 3 dimensions using in vivo micro-CT. Alveolar bone resorption and root resorption were observed mostly in the apical third on day 7 on the compression side; bone formation was observed on day 14 on the tension side during orthodontic tooth movement.

Maternal separation affects dopamine transporter function in the Spontaneously Hypertensive Rat: An in vivo electrochemical study

Directory of Open Access Journals (Sweden)

Womersley Jacqueline S

2011-12-01

Full Text Available Abstract Background Attention-deficit/hyperactivity disorder (ADHD is a developmental disorder characterised by symptoms of inattention, impulsivity and hyperactivity. The spontaneously hypertensive rat (SHR is a well-characterised model of this disorder and has been shown to exhibit dopamine dysregulation, one of the hypothesised causes of ADHD. Since stress experienced in the early stages of life can have long-lasting effects on behaviour, it was considered that early life stress may alter development of the dopaminergic system and thereby contribute to the behavioural characteristics of SHR. It was hypothesized that maternal separation would alter dopamine regulation by the transporter (DAT in ways that distinguish SHR from control rat strains. Methods SHR and control Wistar-Kyoto (WKY rats were subjected to maternal separation for 3 hours per day from postnatal day 2 to 14. Rats were tested for separation-induced anxiety-like behaviour followed by in vivo chronoamperometry to determine whether changes had occurred in striatal clearance of dopamine by DAT. The rate of disappearance of ejected dopamine was used as a measure of DAT function. Results Consistent with a model for ADHD, SHR were more active than WKY in the open field. SHR entered the inner zone more frequently and covered a significantly greater distance than WKY. Maternal separation increased the time that WKY spent in the closed arms and latency to enter the open arms of the elevated plus maze, consistent with other rat strains. Of note is that, maternal separation failed to produce anxiety-like behaviour in SHR. Analysis of the chronoamperometric data revealed that there was no difference in DAT function in the striatum of non-separated SHR and WKY. Maternal separation decreased the rate of dopamine clearance (k-1 in SHR striatum. Consistent with this observation, the dopamine clearance time (T100 was increased in SHR. These results suggest that the chronic mild stress of

In vivo MR imaging of nanometer magnetically labeled bone marrow stromal cells transplanted via portal vein in rat liver

International Nuclear Information System (INIS)

Wang Ping; Wang Jianhua; Yan Zhiping; Hu Meiyu; Xu Pengju; Zhou Meiling; Ya Fuhua; Fan Sheung-tat; Luk John-m

2006-01-01

Objective: To evaluate in vivo magnetic resonance imaging with a conventional 1.5-T system for tracking of intra-portal vein transplantation nanometer magnetically labeled BMSCs in rat liver. Methods: BMSCs were isolated from 5 SD rats bone marrow with the density gradient centrifugation method. Then BMSCs were labeled with nanometer superpara-magnetic iron oxide and transfection agent. Cell labeling efficiency was assessed with determination of the percentage of Peris Prussian blue stain. Then BMSCs transplanted into normal rats' livers via portal vein. The receipts were divided into 5 groups ,including sham control,2 h ,3 d,7 d and 2 w after transplantation. Follow-up serial T 1 WI,T 2 WI and T 2 * -weighted gradient- echo MR imaging were performed at 1.5 T MRI system. MR imaging findings were compared with histology. Results: Cell labeling efficiency was more than 95% by Perls Prussian blue stain. After transplantation of labeled BMSCs via portal vein, liver's had diffuse granular signal intensity appearance in T 2 * WI MRI. Cells were detected for up to 2 w in receipts' liver's. At histologic analysis, signal intensity loss correlated with iron-loaded cells. Conclusion: MR imaging could aid in monitoring of magnetically labeled BMSCs administered via portal vein in vivo. (authors)

Rat liver contains a limited number of binding sites for hepatic lipase

NARCIS (Netherlands)

G.C. Schoonderwoerd (Kees); A.J.M. Verhoeven (Adrie); H. Jansen (Hans)

1994-01-01

textabstractThe binding of hepatic lipase to rat liver was studied in an ex vivo perfusion model. The livers were perfused with media containing partially purified rat hepatic lipase or bovine milk lipoprotein lipase. The activity of the enzymes was determined in the

Binding of in vivo administrated 125-I-triiodothyronine by the rat liver mitochondria

International Nuclear Information System (INIS)

Fiedorowicz, K.; Nauman, A.; Nauman, J.

1979-01-01

In vivo administrated 125 I-triiodothyronine ( 125 I-T 3 ) was bound by the rat liver mitochondria. About 10 % of hormone was bound with external mitochondrial membrane while the remaining part with matrix and inner mitochondrial membrane. The highest accumulation of 125 I-T 3 in mitochondria was observed 30 min after injection while in the whole liver homogenate the highest hormone accumulation appeared 15 min post injection. Mitochondrial binding sites have a great capacity for T 3 which makes impossible estimation of the kinetic parameters of triiodothyronine-mitochondrium interaction by means of saturation and displacement of 125 I-T 3 . (author)

Fenproporex N-dealkylation to amphetamine--enantioselective in vitro studies in human liver microsomes as well as enantioselective in vivo studies in Wistar and Dark Agouti rats.

Science.gov (United States)

Kraemer, Thomas; Pflugmann, Thomas; Bossmann, Michael; Kneller, Nicole M; Peters, Frank T; Paul, Liane D; Springer, Dietmar; Staack, Roland F; Maurer, Hans H

2004-09-01

Fenproporex (FP) is known to be N-dealkylated to R(-)-amphetamine (AM) and S(+)-amphetamine. Involvement of the polymorphic cytochrome P450 (CYP) isoform CYP2D6 in metabolism of such amphetamine precursors is discussed controversially in literature. In this study, the human hepatic CYPs involved in FP dealkylation were identified using recombinant CYPs and human liver microsomes (HLM). These studies revealed that not only CYP2D6 but also CYP1A2, CYP2B6 and CYP3A4 catalyzed this metabolic reaction for both enantiomers with slight preference for the S(+)-enantiomer. Formation of amphetamine was not significantly changed by quinidine and was not different in poor metabolizer HLM compared to pooled HLM. As in vivo experiments, blood levels of R(-)-amphetamine and S(+)-amphetamine formed after administration of FP were determined in female Dark Agouti rats (fDA), a model of the human CYP2D6 poor metabolizer phenotype (PM), male Dark Agouti rats (mDA), an intermediate model, and in male Wistar rats (WI), a model of the human CYP2D6 extensive metabolizer phenotype. Analysis of the plasma samples showed that fDA exhibited significantly higher plasma levels of both amphetamine enantiomers compared to those of WI. Corresponding plasma levels in mDA were between those in fDA and WI. Furthermore, pretreatment of WI with the CYP2D inhibitor quinine resulted in significantly higher amphetamine plasma levels, which did not significantly differ from those in fDA. The in vivo studies suggested that CYP2D6 is not crucial to the N-dealkylation but to another metabolic step, most probably to the ring hydroxylation. Further studies are necessary for elucidating the role of CYP2D6 in FP hydroxylation.

Varenicline increases in vivo striatal dopamine D2/3 receptor binding: an ultra-high-resolution pinhole [123I]IBZM SPECT study in rats

International Nuclear Information System (INIS)

Crunelle, Cleo L.; Wit, Tim C. de; Bruin, Kora de; Ramakers, Ruud M.; Have, Frans van der; Beekman, Freek J.; Brink, Wim van den; Booij, Jan

2012-01-01

Introduction: Ex vivo storage phosphor imaging rat studies reported increased brain dopamine D 2/3 receptor (DRD 2/3 ) availability following treatment with varenicline, a nicotinergic drug. However, ex vivo studies can only be performed using cross-sectional designs. Small-animal imaging offers the opportunity to perform serial assessments. We evaluated whether high-resolution pinhole single photon emission computed tomography (SPECT) imaging in rats was able to reproduce previous ex vivo findings. Methods: Rats were imaged for baseline striatal DRD 2/3 availability using ultra-high-resolution pinhole SPECT (U-SPECT-II) and [ 123 I]IBZM as a radiotracer, and randomized to varenicline (n=7; 2 mg/kg) or saline (n=7). Following 2 weeks of treatment, a second scan was acquired. Results: Significantly increased striatal DRD 2/3 availability was found following varenicline treatment compared to saline (time⁎treatment effect): posttreatment difference in binding potential between groups corrected for initial baseline differences was 2.039 (P=.022), indicating a large effect size (d=1.48). Conclusions: Ultra-high-resolution pinhole SPECT can be used to assess varenicline-induced changes in DRD 2/3 availability in small laboratory animals over time. Future small-animal studies should include imaging techniques to enable repeated within-subjects measurements and reduce the amount of animals.

A study of the uptake and biodistribution of nano-titanium dioxide using in vitro and in vivo models of oral intake

Energy Technology Data Exchange (ETDEWEB)

MacNicoll, Alan; Kelly, Mick [The Food and Environment Research Agency (United Kingdom); Aksoy, Hatice [TÜBİTAK Marmara Research Center, Food Institute (Turkey); Kramer, Evelien; Bouwmeester, Hans [RIKILT - Institute of Food Safety (Netherlands); Chaudhry, Qasim, E-mail: qasim.chaudhry@fera.gsi.gov.uk [The Food and Environment Research Agency (United Kingdom)

2015-02-15

Certain food additives may contain a sizeable fraction of particles in the nanoscale. However, little is known about the fate, behaviour and toxicological effects of orally-ingested nanoparticles. This study investigated the uptake and biodistribution of nano- and larger-sized titanium dioxide (TiO{sub 2}) using an in vitro model of gut epithelium and in vivo in rat. The results of the in vivo study showed that oral administration of 5 mg/kg body weight of TiO{sub 2} nano- or larger particles did not lead to any significant translocation of TiO{sub 2} (measured as titanium) either to blood, urine or to various organs in rat at any of the time intervals studied over a 96 h post-administration period. Different methods used for dispersing particles did not affect the uptake, and orally administered TiO{sub 2} was found excreted in the faeces over a period of time. The in vitro study provided further evidence for the lack of translocation of TiO{sub 2} across the gut epithelium model. The overall evidence from both in vivo and in vitro studies did not support that oral ingestion of nano- or larger particles of TiO{sub 2} via food would result in any significant internal exposure of the consumer to the nanoparticles. The dietary TiO{sub 2} nanoparticles are likely to be excreted in the faeces.

Manganese-induced hydroxyl radical formation in rat striatum is not attenuated by dopamine depletion or iron chelation in vivo

NARCIS (Netherlands)

W.N. Sloot (W.); J. Korf (Jakob); J.F. Koster (Johan); L.E.A. de Wit (Elly); J.-B.P. Gramsbergen (J. B P)

1996-01-01

textabstractThe present studies were aimed at investigating the possible roles of dopamine (DA) and iron in production of hydroxyl radicals (.OH) in rat striatum after Mn2+ intoxication. For this purpose, DA depletions were assessed concomitant with in vivo 2,3- and 2,5-dihydroxybenzoic acid (DHBA)

Nitrite-Mediated Hypoxic Vasodilation Predicted from Mathematical Modeling and Quantified from in Vivo Studies in Rat Mesentery

Directory of Open Access Journals (Sweden)

Donald G. Buerk

2017-12-01

Full Text Available Nitric oxide (NO generated from nitrite through nitrite reductase activity in red blood cells has been proposed to play a major role in hypoxic vasodilation. However, we have previously predicted from mathematical modeling that much more NO can be derived from tissue nitrite reductase activity than from red blood cell nitrite reductase activity. Evidence in the literature suggests that tissue nitrite reductase activity is associated with xanthine oxidoreductase (XOR and/or aldehyde oxidoreductase (AOR. We investigated the role of XOR and AOR in nitrite-mediated vasodilation from computer simulations and from in vivo exteriorized rat mesentery experiments. Vasodilation responses to nitrite in the superfusion medium bathing the mesentery equilibrated with 5% O2 (normoxia or zero O2 (hypoxia at either normal or acidic pH were quantified. Experiments were also conducted following intraperitoneal (IP injection of nitrite before and after inhibiting XOR with allopurinol or inhibiting AOR with raloxifene. Computer simulations for NO and O2 transport using reaction parameters reported in the literature were also conducted to predict nitrite-dependent NO production from XOR and AOR activity as a function of nitrite concentration, PO2 and pH. Experimentally, the largest arteriolar responses were found with nitrite >10 mM in the superfusate, but no statistically significant differences were found with hypoxic and acidic conditions in the superfusate. Nitrite-mediated vasodilation with IP nitrite injections was reduced or abolished after inhibiting XOR with allopurinol (p < 0.001. Responses to IP nitrite before and after inhibiting AOR with raloxifene were not as consistent. Our mathematical model predicts that under certain conditions, XOR and AOR nitrite reductase activity in tissue can significantly elevate smooth muscle cell NO and can serve as a compensatory pathway when endothelial NO production is limited by hypoxic conditions. Our theoretical and

Visualization of haemophilic arthropathy in F8(-/-) rats by ultrasonography and micro-computed tomography

DEFF Research Database (Denmark)

Christensen, K R; Roepstorff, K; Petersen, M

2017-01-01

opportunities. Recently, a F8(-/-) rat model of HA was developed. The size of the rat allows for convenient and high resolution imaging of the joints, which could enable in vivo studies of HA development. AIM: To determine whether HA in the F8(-/-) rat can be visualized using ultrasonography (US) and micro......-computed tomography (μCT). METHODS: Sixty F8(-/-) and 20 wild-type rats were subjected to a single or two induced knee bleeds. F8(-/-) rats were treated with either recombinant human FVIII (rhFVIII) or vehicle before the induction of knee bleeds. Haemophilic arthropathy was visualized using in vivo US and ex vivo μCT......, and the observations correlated with histological evaluation. RESULTS: US and μCT detected pathologies in the knee related to HA. There was a strong correlation between disease severity determined by μCT and histopathology. rhFVIII treatment reduced the pathology identified with both imaging techniques. CONCLUSION: US...

Expression of non-neuronal cholinergic system in maxilla of rat in vivo

Directory of Open Access Journals (Sweden)

Jie Guo

2014-01-01

Full Text Available BACKGROUND: Acetylcholine (ACh is known to be a key neurotransmitter in the central and peripheral nervous systems, which is also produced in a variety of non-neuronal tissues and cell. The existence of ACh in maxilla in vivo and potential regulation role for osteogenesis need further study. RESULTS: Components of the cholinergic system (ACh, esterase, choline acetyltransferase, high-affinity choline uptake, n- and mAChRs were determined in maxilla of rat in vivo, by means of Real-Time PCR and immunohistochemistry. Results showed RNA for CarAT, carnitine/acylcarnitine translocase member 20 (Slc25a20, VAChT, OCTN2, OCT1, OCT3, organic cation transporter member 4 (Slc22a4, AChE, BChE, nAChR subunits α1, α2, α3, α5, α7, α10, β1, β2, β4, γ and mAChR subunits M1, M2, M3, M4, M5 were detected in rat's maxilla. RNA of VAChT, AChE, nAChR subunits α2, β1, β4 and mAChR subunits M4 had abundant expression (2-ΔCt > 0.03. Immunohistochemical staining was conducted for ACh, VAChT, nAChRα7 and AChE. ACh was expressed in mesenchymal cells, chondroblast, bone and cartilage matrix and bone marrow cells, The VAChT expression was very extensively while ACh receptor α7 was strongly expressed in newly formed bone matrix of endochondral and bone marrow ossification, AchE was found only in mesenchymal stem cells, cartilage and bone marrow cells. CONCLUSIONS: ACh might exert its effect on the endochondral and bone marrow ossification, and bone matrix mineralization in maxilla.

The Hepatoprotection Provided by Taurine and Glycine against Antineoplastic Drugs Induced Liver Injury in an Ex Vivo Model of Normothermic Recirculating Isolated Perfused Rat Liver

Directory of Open Access Journals (Sweden)

Reza Heidari

2016-03-01

Full Text Available Taurine (2-aminoethane sulfonic acid is a non-protein amino acid found in high concentration in different tissues. Glycine (Amino acetic acid is the simplest amino acid incorporated in the structure of proteins. Several investigations indicate the hepatoprotective properties of these amino acids. On the other hand, antineoplastic agents-induced serum transaminase elevation and liver injury is a clinical complication. The current investigation was designed to screen the possible hepatoprotective properties of taurine and glycine against antineoplastic drugs-induced hepatic injury in an ex vivo model of isolated perfused rat liver. Rat liver was perfused with different concentration (10 μM, 100 μM and 1000 μM of antineoplastic drugs (Mitoxantrone, Cyclophosphamide, Cisplatin, 5 Fluorouracil, Doxorubicin and Dacarbazine via portal vein. Taurine and glycine were administered to drug-treated livers and liver perfusate samples were collected for biochemical measurements (ALT, LDH, AST, and K+. Markers of oxidative stress (reactive oxygen species formation, lipid peroxidation, total antioxidant capacity and glutathione were also assessed in liver tissue. Antineoplastic drugs caused significant pathological changes in perfusate biochemistry. Furthermore, markers of oxidative stress were significantly elevated in drug treated livers. It was found that taurine (5 and 10 mM and glycine (5 and 10 mM administration significantly mitigated the biomarkers of liver injury and attenuated drug induced oxidative stress. Our data indicate that taurine and glycine supplementation might help as potential therapeutic options to encounter anticancer drugs-induced liver injury.

Single-cell resolution imaging of retinal ganglion cell apoptosis in vivo using a cell-penetrating caspase-activatable peptide probe.

Directory of Open Access Journals (Sweden)

Xudong Qiu

Full Text Available Peptide probes for imaging retinal ganglion cell (RGC apoptosis consist of a cell-penetrating peptide targeting moiety and a fluorophore-quencher pair flanking an effector caspase consensus sequence. Using ex vivo fluorescence imaging, we previously validated the capacity of these probes to identify apoptotic RGCs in cell culture and in an in vivo rat model of N-methyl- D-aspartate (NMDA-induced neurotoxicity. Herein, using TcapQ488, a new probe designed and synthesized for compatibility with clinically-relevant imaging instruments, and real time imaging of a live rat RGC degeneration model, we fully characterized time- and dose-dependent probe activation, signal-to-noise ratios, and probe safety profiles in vivo. Adult rats received intravitreal injections of four NMDA concentrations followed by varying TcapQ488 doses. Fluorescence fundus imaging was performed sequentially in vivo using a confocal scanning laser ophthalmoscope and individual RGCs displaying activated probe were counted and analyzed. Rats also underwent electroretinography following intravitreal injection of probe. In vivo fluorescence fundus imaging revealed distinct single-cell probe activation as an indicator of RGC apoptosis induced by intravitreal NMDA injection that corresponded to the identical cells observed in retinal flat mounts of the same eye. Peak activation of probe in vivo was detected 12 hours post probe injection. Detectable fluorescent RGCs increased with increasing NMDA concentration; sensitivity of detection generally increased with increasing TcapQ488 dose until saturating at 0.387 nmol. Electroretinography following intravitreal injections of TcapQ488 showed no significant difference compared with control injections. We optimized the signal-to-noise ratio of a caspase-activatable cell penetrating peptide probe for quantitative non-invasive detection of RGC apoptosis in vivo. Full characterization of probe performance in this setting creates an important in

Neuroprotective effect of Buddleja cordata methanolic extract in the 1-methyl-4-phenylpyridinium Parkinson's disease rat model.

Science.gov (United States)

Pérez-Barrón, Gabriela; Avila-Acevedo, José Guillermo; García-Bores, Ana María; Montes, Sergio; García-Jiménez, Sara; León-Rivera, Ismael; Rubio-Osornio, Moisés; Monroy-Noyola, Antonio

2015-01-01

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the irreversible loss of dopaminergic neurons in the nigrostriatal pathway with subsequent dopamine deficiency. Environmental causes have been proposed through molecules, such as 1-methyl-4-phenylpyridinium (MPP(+)), to induce oxidative stress. The methanolic extract of plants of the genus Buddleja has been reported to have in vitro and in vivo antioxidant properties to protect against neuronal death. In the present study, the neuroprotective effect of Buddleja cordata methanolic extract in the MPP(+) PD rat model was investigated. Animals were administered orally with 50 or 100 mg/kg of methanolic extract every 24 h for 14 days. Twenty hours later, rats were infused with an intrastriatal stereotaxic microinjection of 10 µg MPP(+) in 8 μl sterile saline solution. Six days later, the animals were treated with 1 mg/kg apomorphine to record ipsilateral rotations for 1 h. All the rats were killed by decapitation and the lesioned striatum was dissected for dopamine and lipid peroxidation quantifications. Both methanolic extract doses led to a significantly lower (P Buddleja cordata methanolic extract in the MPP(+) PD rat model, possibly due to the involvement of phenylpropanoids.

Dipyridamole reduces penile apoptosis in a rat model of post-prostatectomy erectile dysfunction

Directory of Open Access Journals (Sweden)

Omer Kutlu

Full Text Available ABSTRACT Purpose: Despite the nerve-sparing technique, many patients suffer from erectile dysfunction after radical prostatectomy (RP due to cavernous nerve injury. The aim of this study was to evaluate dipyridamole as a potential treatment agent of post-radical prostatectomy erectile dysfunction. Material and methods: A total of 18 male Sprague-Dawley rats were randomized into three experimental Groups (SHAM+DMSO, BCNI+DMSO and BCNI+DIP. An animal model of bilateral cavernous nerve crush injury (BCNI was established to mimic the partial nerve damage during nerve-sparing RP. After creating of BCNI, dimethyl sulphoxide (DMSO was administered transperitoneally as a vehicle to SHAM+DMSO and BCNI+DMSO Groups. BCNI+DIP Group received dipyiridamole (10mg/kg/day as a solution in DMSO for 15 days. Afterwards, rats were evaluated for in vivo erectile response to cavernous nerve stimulation. Penile tissues were also analyzed biochemically for transforming growth factor-β1 (TGF-β1 level. Penile corporal apoptosis was determined by TUNEL method. Results: Erectile response was decreased in rats with BCNI and there was no significant improvement with dipyridamole treatment. TGF-β1 levels were increased in rats with BCNI and decreased with dipyridamole treatment. Dipyridamole led to reduced penile apoptosis in rats with BCNI and there was no significant difference when compared to sham operated rats. Conclusions: Although fifteen-day dipyridamole treatment has failed to improve erectile function in rats with BCNI, the decline in both TGF-β1 levels and apoptotic indices with treatment may be helpful in protecting penile morphology after cavernous nerve injury.

Effect of isologous and autologous insulin antibodies on in vivo bioavailability and metabolic fate of immune-complexed insulin in Lou/M rats

International Nuclear Information System (INIS)

Arquilla, E.R.; McDougall, B.R.; Stenger, D.P.

1989-01-01

The in vivo bioavailability, distribution, and metabolic fate of 125I-labeled insulin complexed to isologous and autologous antibodies were studied in inbred Lou/M rats. There was an impaired bioavailability of the 125I-insulin bound to the isologous and autologous antibodies. Very little of the 125I-insulin in these immune complexes could bind to insulin receptors on hepatocytes or renal tubular cells and be degraded, because the amounts of 125I from degraded 125I-insulin in the blood or secreted into the stomach were markedly attenuated in both cases for at least 30 min after injection. There was a simultaneous accumulation of 125I-insulin immune complexes in the liver and the kidneys of Lou/M rats injected with 125I-insulin complexed with isologous antibodies or when insulin-immunized Lou/M rats were injected with 125I-insulin during the same interval. The impaired bioavailability of immune-complexed insulin and altered distribution of radioactivity due to the accumulation of immune complexes in the liver and kidney were also observed in previous experiments in which Lewis rats were injected with xenogenic guinea pig and homologous insulin antibodies. These observations are therefore submitted as evidence that the Lou/M rat is a valid model in which to study the bioavailability of insulin immune complexed to isologous, homologous, and xenogenic antibodies and the metabolic fate of the respective insulin-antibody immune complexes

Patterns of gene expression associated with recovery and injury in heat-stressed rats

OpenAIRE

Stallings, Jonathan D; Ippolito, Danielle L; Rakesh, Vineet; Baer, Christine E; Dennis, William E; Helwig, Bryan G; Jackson, David A; Leon, Lisa R; Lewis, John A; Reifman, Jaques

2014-01-01

Background The in vivo gene response associated with hyperthermia is poorly understood. Here, we perform a global, multiorgan characterization of the gene response to heat stress using an in vivo conscious rat model. Results We heated rats until implanted thermal probes indicated a maximal core temperature of 41.8?C (Tc,Max). We then compared transcriptomic profiles of liver, lung, kidney, and heart tissues harvested from groups of experimental animals at Tc,Max, 24 hours, and 48 hours after ...

A new in vitro lipid digestion - in vivo absorption model to evaluate the mechanisms of drug absorption from lipid-based formulations.

Science.gov (United States)

Crum, Matthew F; Trevaskis, Natalie L; Williams, Hywel D; Pouton, Colin W; Porter, Christopher J H

2016-04-01

In vitro lipid digestion models are commonly used to screen lipid-based formulations (LBF), but in vitro-in vivo correlations are in some cases unsuccessful. Here we enhance the scope of the lipid digestion test by incorporating an absorption 'sink' into the experimental model. An in vitro model of lipid digestion was coupled directly to a single pass in situ intestinal perfusion experiment in an anaesthetised rat. The model allowed simultaneous real-time analysis of the digestion and absorption of LBFs of fenofibrate and was employed to evaluate the influence of formulation digestion, supersaturation and precipitation on drug absorption. Formulations containing higher quantities of co-solvent and surfactant resulted in higher supersaturation and more rapid drug precipitation in vitro when compared to those containing higher quantities of lipid. In contrast, when the same formulations were examined using the coupled in vitro lipid digestion - in vivo absorption model, drug flux into the mesenteric vein was similar regardless of in vitro formulation performance. For some drugs, simple in vitro lipid digestion models may underestimate the potential for absorption from LBFs. Consistent with recent in vivo studies, drug absorption for rapidly absorbed drugs such as fenofibrate may occur even when drug precipitation is apparent during in vitro digestion.

Multifunctional nanoparticle platforms for in vivo MRI enhancement and photodynamic therapy of a rat brain cancer

International Nuclear Information System (INIS)

Kopelman, Raoul; Lee Koo, Yong-Eun; Philbert, Martin; Moffat, Bradford A.; Ramachandra Reddy, G.; McConville, Patrick; Hall, Daniel E.; Chenevert, Thomas L.; Bhojani, Mahaveer Swaroop; Buck, Sarah M.; Rehemtulla, Alnawaz; Ross, Brian D.

2005-01-01

A paradigm for brain cancer detection, treatment, and monitoring is established. Multifunctional biomedical nanoparticles (30-60 nm) containing photosensitizer externally deliver reactive oxygen species (ROS) to cancer cells while simultaneously enhancing magnetic resonance imaging (MRI) contrast providing real-time tumor kill measurement. Plasma residence time control and specific cell targeting are achieved. A 5 min treatment in rats halted and even reversed in vivo tumor growth after 3-4 days post-treatment

Multifunctional nanoparticle platforms for in vivo MRI enhancement and photodynamic therapy of a rat brain cancer

Energy Technology Data Exchange (ETDEWEB)

Kopelman, Raoul [Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor MI 48109 (United States)]. E-mail: kopelman@umich.edu; Lee Koo, Yong-Eun [Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor MI 48109 (United States); Philbert, Martin [Environmental Health Sciences, niversity of Michigan (United States); Moffat, Bradford A. [Department of Radiology, The University of Michigan (United States); Ramachandra Reddy, G. [Molecular Therapeutics, Inc., Ann Arbor, MI 48104 (United States); McConville, Patrick [Molecular Therapeutics, Inc., Ann Arbor, MI 48104 (United States); Hall, Daniel E. [Department of Radiology, University of Michigan (United States); Chenevert, Thomas L. [Department of Radiology, University of Michigan (United States); Bhojani, Mahaveer Swaroop [Department of Radiation Oncology, University of Michigan (United States); Buck, Sarah M. [Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor MI 48109 (United States); Rehemtulla, Alnawaz [Department of Radiation Oncology, University of Michigan (United States); Ross, Brian D. [Department of Radiology, University of Michigan (United States)

2005-05-15

A paradigm for brain cancer detection, treatment, and monitoring is established. Multifunctional biomedical nanoparticles (30-60 nm) containing photosensitizer externally deliver reactive oxygen species (ROS) to cancer cells while simultaneously enhancing magnetic resonance imaging (MRI) contrast providing real-time tumor kill measurement. Plasma residence time control and specific cell targeting are achieved. A 5 min treatment in rats halted and even reversed in vivo tumor growth after 3-4 days post-treatment.

Multifunctional nanoparticle platforms for in vivo MRI enhancement and photodynamic therapy of a rat brain cancer

Science.gov (United States)

Kopelman, Raoul; Lee Koo, Yong-Eun; Philbert, Martin; Moffat, Bradford A.; Ramachandra Reddy, G.; McConville, Patrick; Hall, Daniel E.; Chenevert, Thomas L.; Bhojani, Mahaveer Swaroop; Buck, Sarah M.; Rehemtulla, Alnawaz; Ross, Brian D.

2005-05-01

A paradigm for brain cancer detection, treatment, and monitoring is established. Multifunctional biomedical nanoparticles (30-60 nm) containing photosensitizer externally deliver reactive oxygen species (ROS) to cancer cells while simultaneously enhancing magnetic resonance imaging (MRI) contrast providing real-time tumor kill measurement. Plasma residence time control and specific cell targeting are achieved. A 5 min treatment in rats halted and even reversed in vivo tumor growth after 3-4 days post-treatment.

In-vivo generation of bone via endochondral ossification by in-vitro chondrogenic priming of adult human and rat mesenchymal stem cells

LENUS (Irish Health Repository)

Farrell, Eric

2011-01-31

Abstract Background Bone grafts are required to repair large bone defects after tumour resection or large trauma. The availability of patients\\' own bone tissue that can be used for these procedures is limited. Thus far bone tissue engineering has not lead to an implant which could be used as alternative in bone replacement surgery. This is mainly due to problems of vascularisation of the implanted tissues leading to core necrosis and implant failure. Recently it was discovered that embryonic stem cells can form bone via the endochondral pathway, thereby turning in-vitro created cartilage into bone in-vivo. In this study we investigated the potential of human adult mesenchymal stem cells to form bone via the endochondral pathway. Methods MSCs were cultured for 28 days in chondrogenic, osteogenic or control medium prior to implantation. To further optimise this process we induced mineralisation in the chondrogenic constructs before implantation by changing to osteogenic medium during the last 7 days of culture. Results After 8 weeks of subcutaneous implantation in mice, bone and bone marrow formation was observed in 8 of 9 constructs cultured in chondrogenic medium. No bone was observed in any samples cultured in osteogenic medium. Switch to osteogenic medium for 7 days prevented formation of bone in-vivo. Addition of β-glycerophosphate to chondrogenic medium during the last 7 days in culture induced mineralisation of the matrix and still enabled formation of bone and marrow in both human and rat MSC cultures. To determine whether bone was formed by the host or by the implanted tissue we used an immunocompetent transgenic rat model. Thereby we found that osteoblasts in the bone were almost entirely of host origin but the osteocytes are of both host and donor origin. Conclusions The preliminary data presented in this manuscript demonstrates that chondrogenic priming of MSCs leads to bone formation in vivo using both human and rat cells. Furthermore, addition of �

In vivo layer visualization of rat olfactory bulb by a swept source optical coherence tomography and its confirmation through electrocoagulation and anatomy

Science.gov (United States)

Watanabe, Hideyuki; Rajagopalan, Uma Maheswari; Nakamichi, Yu; Igarashi, Kei M.; Madjarova, Violeta Dimitrova; Kadono, Hirofumi; Tanifuji, Manabu

2011-01-01

Here, we report in vivo 3-D visualization of the layered organization of a rat olfactory bulb (OB) by a swept source optical coherence tomography (SS-OCT). The SS-OCT operates at a wavelength of 1334 nm with respective theoretical depth and lateral resolutions of 6.7 μm and 15.4 μm in air and hence it is possible to get a 3D structural map of OB in vivo at the micron level resolution with millimeter-scale imaging depth. Up until now, with methods such as MRI, confocal microscopy, OB depth structure in vivo had not been clearly visualized as these do not satisfy the criterion of simultaneously providing micron-scale spatial resolution and imaging up to a few millimeter in depth. In order to confirm the OB’s layered organization revealed by SS-OCT, we introduced the technique of electrocoagulation to make landmarks across the layered structure. To our knowledge this is such a first study that combines electrocoagulation and OCT in vivo of rat OB. Our results confirmed the layered organization of OB, and moreover the layers were clearly identified by electrocoagulation landmarks both in the OCT structural and anatomical slice images. We expect such a combined study is beneficial for both OCT and neuroscience fields. PMID:21833364

Proteolysis of His-Phe-Arg-Trp-Pro-Gly-Pro in the blood and brain of rats in vivo.

Science.gov (United States)

Shevchenko, K V; Nagaev, I Yu; Babakov, V N; Andreeva, L A; Shevchenko, V P; Radilov, A S; Myasoedov, N F

2015-01-01

The kinetics of the content of His-Phe-Arg-Trp-Pro-Gly-Pro (ACTH (6-9)PGP) and its hydrolysis products in the blood and brain of rats in the case of intranasal administration and intravenous injection of tritiated ACTH(6-9)PGP was studied. The parameters of bioavailability of ACTH(6-9)PGP administered intranasally were higher, indicating certain prospects in the intranasal application in clinical practice. We also found that the factor that determines ACTH(6-9)PGP proteolysis in experiments both in vivo and in vitro is aminopeptidases. The main products of ACTH(6-9)PGP during its metabolism in rats are short peptides and amino acids.

Simultaneous in vivo determination of calcium and phosphate effective intestinal absorption in the rat

International Nuclear Information System (INIS)

Ladizesky, M.; Mautalen, C.A.; Cabrejas, M.; Degrossi, O.J.

1978-01-01

A description is given of a technique which allows a more precise assessment of the interrelation between calcium and phosphate transport systems. Rats were given an i.p. or oral dose of 47 Ca with 40 Ca as carrier and/or 32 P with 31 P as carrier. The animals were sacrificed and activities in body and excised gastrointestinal tract determined. The 1.28 MeV photopeak activity was measured for calcium 47, and phosphorus 32 activity was determined by measuring the Bremsstrahlung produced by this isotope in the rat's body in the 80 to 200 keV range. The rates of intestinal absorption of calcium and phosphate differed; there seemed to be no urinary excretion of the radioisotopes within 3 hours. The reciprocal influence of calcium and phosphate on the intestinal absorption was also studied. The technique is simple and allows the simultaneous in vivo measurement of the effective intestinal absorption of calcium and phosphate. (U.K.)

Effects of PDE5 Inhibitors and sGC Stimulators in a Rat Model of Artificial Ureteral Calculosis.

Directory of Open Access Journals (Sweden)

Peter Sandner

Full Text Available Urinary colics from calculosis are frequent and intense forms of pain whose current pharmacological treatment remains unsatisfactory. New and more effective drugs are needed to control symptoms and improve stone expulsion. Recent evidence suggested that the Nitric Oxide (NO / cyclic guanosine monophosphate (cGMP/phosphodiesterase type 5 (PDE5 system may contribute to ureteral motility influencing stone expulsion. We investigated if PDE5 inhibitors and sGC stimulators influence ureteral contractility, pain behaviour and stone expulsion in a rat model of ureteral calculosis. We investigated: a the sex-specific PDE5 distribution in the rat ureter; b the functional in vitro effects of vardenafil and sildenafil (PDE5 inhibitors and BAY41-2272 (sGC stimulator on induced ureteral contractility in rats and c the in vivo effectiveness of vardenafil and BAY41-2272, alone and combined with ketoprofen, vs hyoscine-N-butylbromide alone or combined with ketoprofen, on behavioural pain indicators and stone expulsion in rats with artificial calculosis in one ureter. PDE5 was abundantly expressed in male and female rats' ureter. In vitro, both vardenafil and BAY41-2272 significantly relaxed pre-contracted ureteral strips. In vivo, all compounds significantly reduced number and global duration of "ureteral crises" and post-stone lumbar muscle hyperalgesia in calculosis rats. The highest level of reduction of the pain behaviour was observed with BAY41-2272 among all spasmolytics administered alone, and with the combination of ketoprofen with BAY41-2272. The percentage of stone expulsion was maximal in the ketoprofen+BAY41-2272 group. The NO/cGMP/PDE5 pathway is involved in the regulation of ureteral contractility and pain behaviour in urinary calculosis. PDE5 inhibitors and sGC stimulators could become a potent new option for treatment of urinary colic pain.

Vitamin E Phosphate Coating Stimulates Bone Deposition in Implant-related Infections in a Rat Model.

Science.gov (United States)

Lovati, Arianna B; Bottagisio, Marta; Maraldi, Susanna; Violatto, Martina B; Bortolin, Monica; De Vecchi, Elena; Bigini, Paolo; Drago, Lorenzo; Romanò, Carlo L

2018-06-01

Implant-related infections are associated with impaired bone healing and osseointegration. In vitro antiadhesive and antibacterial properties and in vivo antiinflammatory effects protecting against bone loss of various formulations of vitamin E have been demonstrated in animal models. However, to the best of our knowledge, no in vivo studies have demonstrated the synergistic activity of vitamin E in preventing bacterial adhesion to orthopaedic implants, thus supporting the bone-implant integration. The purpose of this study was to test whether a vitamin E phosphate coating on titanium implants may be able to reduce (1) the bacterial colonization of prosthetic implants and (2) bone resorption and osteomyelitis in a rat model of Staphylococcus aureus-induced implant-related infection. Twelve rats were bilaterally injected in the femurs with S aureus UAMS-1-Xen40 and implanted with uncoated or vitamin E phosphate-coated titanium Kirschner wires without local or systemic antibiotic prophylaxis. Eight rats represented the uninfected control group. A few hours after surgery, two control and three infected animals died as a result of unexpected complications. With the remaining rats, we assessed the presence of bacterial contamination with qualitative bioluminescence imaging and Gram-positive staining and with quantitative bacterial count. Bone changes in terms of resorption and osteomyelitis were quantitatively analyzed through micro-CT (bone mineral density) and semiquantitatively through histologic scoring systems. Six weeks after implantation, we found only a mild decrease in bacterial count in coated versus uncoated implants (Ti versus controls: mean difference [MD], -3.705; 95% confidence interval [CI], -4.416 to -2.994; p E-treated group compared with uncoated implants (knee joint: MD, -11.88; 95% CI, -16.100 to -7.664; p E-coated nails compared with the uncoated nails. These preliminary findings indicate that vitamin E phosphate implant coatings can exert a

Closure of multiple types of K+ channels is necessar to induce changes in renal vascular resistance in vivo in rats

DEFF Research Database (Denmark)

Sørensen, Charlotte Mehlin; Giese, Isaiah; Braunstein, Thomas Hartig

2011-01-01

Inhibition of K(+) channels might mediate renal vasoconstriction. As inhibition of a single type of K(+) channel caused minor or no renal vasoconstriction in vivo in rats, we hypothesized that several classes of K(+) channels must be blocked to elicit renal vasoconstriction. We measured renal blo...

Iodine-123 labelled nor-beta-CIT binds to the serotonin transporter in vivo as assessed by biodistribution studies in rats

NARCIS (Netherlands)

Booij, J.; Knol, R. J.; Reneman, L.; de Bruin, K.; Janssen, A. G.; van Royen, E. A.

1998-01-01

Iodine-123 labelled 2beta-carbomethoxy-3beta-4-iodophenylnortropane (nor-beta-CIT), a radioiodinated cocaine analogue, was evaluated as an agent for the in vivo labelling of serotonin transporters by biodistribution studies in rats. Intravenous injection of [123I]nor-beta-CIT resulted in high

Development of a high-throughput in vitro assay using a novel Caco-2/rat hepatocyte system for the prediction of oral plasma area under the concentration versus time curve (AUC) in rats.

Science.gov (United States)

Cheng, K-C; Li, Cheng; Hsieh, Yunsheng; Montgomery, Diana; Liu, Tongtong; White, Ronald E

2006-01-01

Previously, we have shown that a novel Caco-2/human hepatocyte system is a useful model for the prediction of oral bioavailability in humans. In this study, we attempted to use a similar system in a high-throughput screening mode for the selection of new compound entities (NCE) in drug discovery. A total of 72 compounds randomly selected from three different chemotypes were dosed orally in rats. In vivo plasma area under the concentration versus time curve (AUC) from 0-6 h of the parent compound was determined. The same compounds were also tested in the Caco-2/rat hepatocyte system. In vitro AUC from 0-3 h in the Caco-2 rat hepatocyte system was determined. The predictive usefulness of the Caco-2/rat hepatocyte system was evaluated by comparing the in vivo plasma AUC and the in vitro AUC. Linear regression analysis showed a reasonable correlation (R2 = 0.5) between the in vivo AUC and the in vitro AUC. Using 0.4 microM h in vivo AUC as a cut-off, compounds were categorized as either low or high AUC. The in vitro AUC successfully matched the corresponding in vivo category for sixty-three out of seventy-two compounds. The results presented in this study suggest that the Caco-2/rat hepatocyte system may be used as a high-throughput screen in drug discovery for pharmacokinetic behaviors of compounds in rats.

Extracellular Vesicles from Human Liver Stem Cells Reduce Injury in an Ex Vivo Normothermic Hypoxic Rat Liver Perfusion Model.

Science.gov (United States)

Rigo, Federica; De Stefano, Nicola; Navarro-Tableros, Victor; David, Ezio; Rizza, Giorgia; Catalano, Giorgia; Gilbo, Nicholas; Maione, Francesca; Gonella, Federica; Roggio, Dorotea; Martini, Silvia; Patrono, Damiano; Salizzoni, Mauro; Camussi, Giovanni; Romagnoli, Renato

2018-05-01

The gold standard for organ preservation before transplantation is static cold storage, which is unable to fully protect suboptimal livers from ischemia/reperfusion injury. An emerging alternative is normothermic machine perfusion (NMP), which permits organ reconditioning. Here, we aimed to explore the feasibility of a pharmacological intervention on isolated rat livers by using a combination of NMP and human liver stem cells-derived extracellular vesicles (HLSC-EV). We established an ex vivo murine model of NMP capable to maintain liver function despite an ongoing hypoxic injury induced by hemodilution. Livers were perfused for 4 hours without (control group, n = 10) or with HLSC-EV (treated group, n = 9). Bile production was quantified; perfusate samples were collected hourly to measure metabolic (pH, pO2, pCO2) and cytolysis parameters (AST, alanine aminotransferase, lactate dehydrogenase). At the end of perfusion, we assessed HLSC-EV engraftment by immunofluorescence, tissue injury by histology, apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, tissue hypoxia-inducible factor 1-α, and transforming growth factor-beta 1 RNA expression by quantitative reverse transcription-polymerase chain reaction. During hypoxic NMP, livers were able to maintain homeostasis and produce bile. In the treated group, AST (P = 0.018) and lactate dehydrogenase (P = 0.032) levels were significantly lower than those of the control group at 3 hours of perfusion, and AST levels persisted lower at 4 hours (P = 0.003). By the end of NMP, HLSC-EV had been uptaken by hepatocytes, and EV treatment significantly reduced histological damage (P = 0.030), apoptosis (P = 0.049), and RNA overexpression of hypoxia-inducible factor 1-α (P < 0.0001) and transforming growth factor-beta 1 (P = 0.014). HLSC-EV treatment, even in a short-duration model, was feasible and effectively reduced liver injury during hypoxic NMP.

Adenovirus vector-mediated ex vivo gene transfer of brain-derived neurotrophic factor (BDNF) tohuman umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) promotescrush-injured rat sciatic nerve regeneration.

Science.gov (United States)

Hei, Wei-Hong; Almansoori, Akram A; Sung, Mi-Ae; Ju, Kyung-Won; Seo, Nari; Lee, Sung-Ho; Kim, Bong-Ju; Kim, Soung-Min; Jahng, Jeong Won; He, Hong; Lee, Jong-Ho

2017-03-16

This study was designed toinvestigate the efficacy of adenovirus vector-mediated brain-derived neurotrophic factor (BDNF) ex vivo gene transfer to human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) in a rat sciatic nerve crush injury model. BDNF protein and mRNA expression after infection was checked through an enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). Male Sprague-Dawley rats (200-250g, 6 weeks old) were distributed into threegroups (n=20 each): the control group, UCB-MSC group, and BDNF-adenovirus infected UCB-MSC (BDNF-Ad+UCB-MSC) group. UCB-MSCs (1×10 6 cells/10μl/rat) or BDNF-Ad+UCB-MSCs (1×10 6 cells/10μl/rat)were transplantedinto the rats at the crush site immediately after sciatic nerve injury. Cell tracking was done with PKH26-labeled UCB-MSCs and BDNF-Ad+UCB-MSCs (1×10 6 cells/10μl/rat). The rats were monitored for 4 weeks post-surgery. Results showed that expression of BDNF at both the protein and mRNA levels was higher inthe BDNF-Ad+UCB-MSC group compared to theUCB-MSC group in vitro.Moreover, BDNF mRNA expression was higher in both UCB-MSC group and BDNF-Ad+ UCB-MSC group compared tothe control group, and BDNF mRNA expression in theBDNF-Ad+UCB-MSC group was higher than inboth other groups 5days after surgeryin vivo. Labeled neurons in the dorsal root ganglia (DRG), axon counts, axon density, and sciatic function index were significantly increased in the UCB-MSC and BDNF-Ad+ UCB-MSCgroupscompared to the controlgroup four weeksaftercell transplantation. Importantly,the BDNF-Ad+UCB-MSCgroup exhibited more peripheral nerve regeneration than the other two groups.Our results indicate thatboth UCB-MSCs and BDNF-Ad+UCB-MSCscan improve rat sciatic nerve regeneration, with BDNF-Ad+UCB-MSCsshowing a greater effectthan UCB-MSCs. Copyright © 2017 Elsevier B.V. All rights reserved.

OKN-007 decreases free radical levels in a preclinical F98 rat glioma model.

Science.gov (United States)

Coutinho de Souza, Patricia; Smith, Nataliya; Atolagbe, Oluwatomisin; Ziegler, Jadith; Njoku, Charity; Lerner, Megan; Ehrenshaft, Marilyn; Mason, Ronald P; Meek, Bill; Plafker, Scott M; Saunders, Debra; Mamedova, Nadezda; Towner, Rheal A

2015-10-01

Free radicals are associated with glioma tumors. Here, we report on the ability of an anticancer nitrone compound, OKN-007 [Oklahoma Nitrone 007; a disulfonyl derivative of α-phenyl-tert-butyl nitrone (PBN)] to decrease free radical levels in F98 rat gliomas using combined molecular magnetic resonance imaging (mMRI) and immunospin-trapping (IST) methodologies. Free radicals are trapped with the spin-trapping agent, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), to form DMPO macromolecule radical adducts, and then further tagged by immunospin trapping by an antibody against DMPO adducts. In this study, we combined mMRI with a biotin-Gd-DTPA-albumin-based contrast agent for signal detection with the specificity of an antibody for DMPO nitrone adducts (anti-DMPO probe), to detect in vivo free radicals in OKN-007-treated rat F98 gliomas. OKN-007 was found to significantly decrease (P free radical levels detected with an anti-DMPO probe in treated animals compared to untreated rats. Immunoelectron microscopy was used with gold-labeled antibiotin to detect the anti-DMPO probe within the plasma membrane of F98 tumor cells from rats administered anti-DMPO in vivo. OKN-007 was also found to decrease nuclear factor erythroid 2-related factor 2, inducible nitric oxide synthase, 3-nitrotyrosine, and malondialdehyde in ex vivo F98 glioma tissues via immunohistochemistry, as well as decrease 3-nitrotyrosine and malondialdehyde adducts in vitro in F98 cells via ELISA. The results indicate that OKN-007 effectively decreases free radicals associated with glioma tumor growth. Furthermore, this method can potentially be applied toward other types of cancers for the in vivo detection of macromolecular free radicals and the assessment of antioxidants. Copyright © 2015. Published by Elsevier Inc.

Ex vivo evaluation of the serotonin 1A receptor partial agonist [³H]CUMI-101 in awake rats

DEFF Research Database (Denmark)

Palner, Mikael; Underwood, Mark D; Kumar, Dileep J S

2011-01-01

[³H]CUMI-101 is a 5-HT(1A) partial agonist, which has been evaluated for use as a positron emission tracer in baboon and humans. We sought to evaluate the properties of [³H]CUMI-101 ex vivo in awake rats and determine if [³H]CUMI-101 can measure changes in synaptic levels of serotonin after diffe...

Interaction of gamma-glutamyltranspeptidase with clofibryl-S-acyl-glutathione in vitro and in vivo in rat.

Science.gov (United States)

Grillo, M P; Benet, L Z

2001-08-01

Clofibric acid (CA) is metabolized to chemically reactive acylating products that can transacylate glutathione to form clofibryl-S-acyl-glutathione (CA-SG) in vitro and in vivo. We investigated the first step in the degradation of CA-SG to the mercapturic acid conjugate, clofibryl-S-acyl-N-acetylcysteine (CA-SNAC), which is catalyzed by gamma-glutamyltranspeptidase (gamma-GT). After gamma-GT mediated cleavage of glutamate from CA-SG, the product clofibryl-S-acyl-cysteinylglycine (CA-S-CG) should undergo an intramolecular rearrangement reaction [Tate, S. S. (1975) FEBS Lett. 54, 319-322] to form clofibryl-N-acyl-cysteinylglycine (CA-N-CG). We performed in vitro studies incubating CA-SG with gamma-GT to determine the products formed, and in vivo studies examining the products excreted in urine after dosing rats with CA-SG or CA. Thus, CA-SG (0.1 mM) was incubated with gamma-GT (0.1 unit/mL) in buffer (pH 7.4, 25 degrees C) and analyzed for products formed by reversed-phase HPLC and electrospray mass spectrometry (ESI/MS). Results showed that CA-SG is degraded completely after 6 h of incubation leading to the formation of two products, CA-N-CG and its disulfide, with no detection of CA-S-CG thioester. After 36 h of incubation, only the disulfide remained in the incubation. Treatment of the disulfide with dithiothreitol led to the reappearance of CA-N-CG. ESI/LC/MS analysis of urine (16 h) extracts of CA-SG-dosed rats (200 mg/kg, iv) showed that CA-SG is degraded to CA-N-CG, CA-N-acyl-cysteine (CA-N-C) and their respective S-methylated products. The mercapturic acid conjugate (CA-SNAC) was found as a minor product. Analysis of urine extracts from CA-dosed rats (200 mg/kg, ip) resulted in the detection of clofibryl-N-acyl-cysteine (CA-N-C), but no evidence for the formation of CA-SNAC was obtained. These in vitro and in vivo experiments indicate that gamma-GT mediated degradation of clofibryl-S-acyl-glutathione leads primarily to the formation and excretion of clofibryl

In vivo turnover of the basement membrane and other heparan sulfate proteoglycans of rat glomerulus

DEFF Research Database (Denmark)

Beavan, L A; Davies, M; Couchman, J R

1989-01-01

The metabolic turnover of rat glomerular proteoglycans in vivo was investigated. Newly synthesized proteoglycans were labeled during a 7-h period after injecting sodium [35S]sulfate intraperitoneally. At the end of the labeling period a chase dose of sodium sulfate was given. Subsequently......-propanesulfonate-4 M guanidine hydrochloride, a procedure which solubilized greater than 95% of the 35S-labeled macromolecules. Of these 11-13% was immunoprecipitated by an antiserum against heparan sulfate proteoglycan which, in immunolocalization experiments, showed specificity for staining the basement membrane...

Tracer kinetics of ω(para-iodophenyl)-pentadecanoic acid (p-IPPA) in vivo wistar rats after dobutamine-induced stress

International Nuclear Information System (INIS)

Zeng Jun; Zhao Huiyang; Huang Gang

1995-01-01

The kinetics of p- 125 IPPA in vivo rats after dobutamine-induced stress was studied in order to develop a method for clinical myocardial imaging. p- 125 IPPA was labelled by solid-phase iodine isotope exchange method. Both dobutamine-induced rats (DIR) and non-induced rats (NIR) (24 rats in each group) were killed in successive intervals at 1, 2, 3, 4, 5, 7, 10 and 25 min after injection of p- 125 IPPA. Radioactivity of heart, blood, lung, liver and kidney in each phase was calculated as percentage of administered dose per g tissue (%ID/g) and glucose, krone-bodies and triglycerides serum levels were also measured. Cardiac uptake of p- 125 IPPA in DIR was 1.5 times (P 1/2 of 5.2 min and 3.4 min respectively. Except the early uptake in liver lowered, the activity in other tissues had not been changed after dobutamine-induced stress, so the ratio of heart-to-lung and heart-to-liver was increased 1.4 and 1.7 times (P<0.05) respectively in early 7 min

Niosomes of Ascorbic Acid and α-Tocopherol in the Cerebral Ischemia-Reperfusion Model in Male Rats

OpenAIRE

Varshosaz, Jaleh; Taymouri, Somayeh; Pardakhty, Abbas; Asadi-Shekaari, Majid; Babaee, Abodolreza

2014-01-01

The objective of the present study was to prepare a stable iv injectable formulation of ascorbic acid and α-tocopherol in preventing the cerebral ischemia. Different niosomal formulations were prepared by Span and Tween mixed with cholesterol. The physicochemical characteristics of niosomal formulations were evaluated in vitro. For in vivo evaluation, the rats were made ischemic by middle cerebral artery occlusion model for 30 min and the selected formulation was used for determining its neur...

Development of a Physiologically-Based Pharmacokinetic Model of the Rat Central Nervous System

Directory of Open Access Journals (Sweden)

Raj K. Singh Badhan

2014-03-01

Full Text Available Central nervous system (CNS drug disposition is dictated by a drug’s physicochemical properties and its ability to permeate physiological barriers. The blood–brain barrier (BBB, blood-cerebrospinal fluid barrier and centrally located drug transporter proteins influence drug disposition within the central nervous system. Attainment of adequate brain-to-plasma and cerebrospinal fluid-to-plasma partitioning is important in determining the efficacy of centrally acting therapeutics. We have developed a physiologically-based pharmacokinetic model of the rat CNS which incorporates brain interstitial fluid (ISF, choroidal epithelial and total cerebrospinal fluid (CSF compartments and accurately predicts CNS pharmacokinetics. The model yielded reasonable predictions of unbound brain-to-plasma partition ratio (Kpuu,brain and CSF:plasma ratio (CSF:Plasmau using a series of in vitro permeability and unbound fraction parameters. When using in vitro permeability data obtained from L-mdr1a cells to estimate rat in vivo permeability, the model successfully predicted, to within 4-fold, Kpuu,brain and CSF:Plasmau for 81.5% of compounds simulated. The model presented allows for simultaneous simulation and analysis of both brain biophase and CSF to accurately predict CNS pharmacokinetics from preclinical drug parameters routinely available during discovery and development pathways.

Characterization of rat model of acute anterior uveitis using optical coherence tomography angiography

Science.gov (United States)

Choi, Woo June; Pepple, Kathryn L.; Zhi, Zhongwei; Wang, Ruikang K.

2015-03-01

Uveitis, or ocular inflammation, is a cause of severe visual impairment. Rodent models of uveitis are powerful tools used to investigate the pathological mechanisms of ocular inflammation and to study the efficacy of new therapies prior to human testing. In this paper, we report the utility of spectral-domain optical coherence tomography (SD-OCT) angiography in characterizing the inflammatory changes induced in the anterior segment of a rat model of uveitis. Acute anterior uveitis (AAU) was induced in two rats by intravitreal injection of a killed mycobacterial extract. One of them received a concurrent periocular injection of steroids to model a treatment effect. OCT imaging was performed prior to inflammation induction on day 0 (baseline), and 2 days post-injection (peak inflammation). Baseline and inflamed images were compared. OCT angiography identified swelling of the cornea, inflammatory cells in the anterior and posterior chambers, a fibrinous papillary membrane, and dilation of iris vessels in the inflamed eyes when compared to baseline images. Steroid treatment was shown to prevent the changes associated with inflammation. This is a novel application of anterior OCT imaging in animal models of uveitis, and provides a high resolution, in vivo assay for detecting and quantifying ocular inflammation and the response to new therapies.

Effects of the neonicotinoids thiametoxam and clothianidin on in vivo dopamine release in rat striatum.

Science.gov (United States)

de Oliveira, Iris Machado; Nunes, Brenda Viviane Ferreira; Barbosa, Durán Rafael; Pallares, Alfonso Miguel; Faro, Lilian Rosana Ferreira

2010-02-15

Thiamethoxam (TMX) and clothianidin (CLO) are neonicotinoids insecticides. The main characteristic of these pesticides is their agonist action on nicotinic acetylcholine receptors (nAChRs). In the present work it was studied and characterized the effects of TMX and CLO, in different concentrations, on dopaminergic system of rat striatum using in vivo brain microdialysis coupled to HPLC-EC. Intrastriatal administration of 1mM or 5mM TMX has not produced significant increases on dopamine (DA) levels, nonetheless the infusion of 10mM TMX increases the DA output to 841+/-132%, when compared to basal levels. Infusion of 1mM CLO has not induced a significant increase in DA levels, even so 2, 3.5 and 5mM CLO have produced an increase of 438+/-8%, 2778+/-598% and 4604+/-516%, respectively, every compared to basal levels. Mecamylamine (MEC), a non-competitive nAChRs antagonist, was used to investigate the role of nAChRs on DA release induced by TMX and CLO. The increases in extracellular DA levels induced by TMX and CLO when associated to MEC are 80% and 68% lower than the effect produced by CLO and TMX isolated. These results confirm that TMX and CLO appear to induce in vivo DA increased release in striatum of rats and it seems to be concentration dependent. Moreover, these results indicate that this effect might be related to nAChRs. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Acute and Subacute Toxicity In Vivo of Thermal-Sprayed Silver Containing Hydroxyapatite Coating in Rat Tibia

Science.gov (United States)

Tsukamoto, Masatsugu; Miyamoto, Hiroshi; Ando, Yoshiki; Eto, Shuichi; Akiyama, Takayuki; Yonekura, Yutaka; Mawatari, Masaaki

2014-01-01

To reduce the incidence of implant-associated infection, we previously developed a novel coating technology using hydroxyapatite (HA) containing silver (Ag). This study examined in vivo acute and subacute toxicity associated with the Ag-HA coating in rat tibiae. Ten-week-old rats received implantation of HA-, 2% Ag-HA-, or 50% Ag-HA-coated titanium rods. Concentrations of silver in serum, brain, liver, kidneys, and spleen were measured in the acute phase (2–4 days after treatment) and subacute phase (4–12 weeks after treatment). Biochemical and histological examinations of those organs were also performed. Mean serum silver concentration peaked in the acute phase and then gradually decreased. Mean silver concentrations in all examined organs from the 2% Ag-HA coating groups showed no significant differences compared with the HA coating group. No significant differences in mean levels of glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, lactate dehydrogenase, creatinine, or blood urea nitrogen were seen between the three groups and controls. Histological examinations of all organs revealed no abnormal pathologic findings. No acute or subacute toxicity was seen in vivo for 2% Ag-HA coating or HA coating. Ag-HA coatings on implants may represent biologically safe antibacterial biomaterials and may be of value for reducing surgical-site infections related to implantation. PMID:24779019

The influence of alendronate on the healing of extraction sockets of ovariectomized rats assessed by in vivo micro-computed tomography.

Science.gov (United States)

Jee, Jeong-Hyun; Lee, Wan; Lee, Byung Do

2010-08-01

Many dental patients take bisphosphonates to reduce the risk of hip and vertebral fractures. In vivo micro-computed tomography (micro-CT) was used to examine the longitudinal inhibitory effect of alendronate on the healing of extraction sockets in ovariectomized rats. Twenty 5-week-old Sprague-Dawley rats were assigned randomly to 1 of 3 groups: sham-operated (n = 5), and 2 ovariectomized (OVX) groups: saline treated (0.1 mL/100 g/d, n = 7) and alendronate treated (1 mg/kg/d, n = 8). Before micro-CT scanning, the left maxillary first molars of the rats were extracted. In vivo micro-CT (spatial resolution 50 x 50 mum) of the jaw was performed at baseline and at 2-week intervals for 6 weeks. Alveolar-bone radiographic densities and dimensions were analyzed with repeated measures analysis of variance. The bony healing patterns of the extraction sockets were also evaluated in each group. The radiographic socket densities of the sham-treated and OVX-alendronate groups significantly increased during the first 4 weeks after extraction (P sockets in the OVX-saline group increased, but the increase was significantly lower than for the other groups at 4 weeks (P sockets in all groups 2 to 6 weeks after extraction. There was a significant loss of alveolar ridge height at the second week postextraction compared with baseline, and at the fourth week compared with the second week (P sockets in estrogen-deficient rats and helps resist the loss of alveolar bone adjacent to extraction sockets. Copyright 2010 Mosby, Inc. All rights reserved.

Alpha2-adrenoceptor modulation of long-term potentiation elicited in vivo in rat occipital cortex.

Science.gov (United States)

Mondaca, Mauricio; Hernández, Alejandro; Pérez, Hernán; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Soto-Moyano, Rubén

2004-09-24

Pretreatment with the alpha(2)-adrenoceptor agonist clonidine (31.25, 62.5, or 125 microg/kg, i.p.) dose-dependently reduced long-term potentiation (LTP) elicited in vivo in the occipital cortex of anesthetized rats, whereas pretreatment with the alpha(2)-adrenoceptor antagonist yohimbine (0.133, 0.4, or 1.2 mg/kg, i.p.) increased neocortical LTP in a dose-dependent fashion. These effects could be related to the reported disruptive and facilitatory actions induced on memory formation by pretreatment with alpha(2)-adrenoceptor agonists and antagonists, respectively.

Niosomes of ascorbic acid and α-tocopherol in the cerebral ischemia-reperfusion model in male rats.

Science.gov (United States)

Varshosaz, Jaleh; Taymouri, Somayeh; Pardakhty, Abbas; Asadi-Shekaari, Majid; Babaee, Abodolreza

2014-01-01

The objective of the present study was to prepare a stable iv injectable formulation of ascorbic acid and α-tocopherol in preventing the cerebral ischemia. Different niosomal formulations were prepared by Span and Tween mixed with cholesterol. The physicochemical characteristics of niosomal formulations were evaluated in vitro. For in vivo evaluation, the rats were made ischemic by middle cerebral artery occlusion model for 30 min and the selected formulation was used for determining its neuroprotective effect against cerebral ischemia. Neuronal damage was evaluated by optical microscopy and transmission electron microscopy. The encapsulation efficiency of ascorbic acid was increased to more than 84% by remote loading method. The cholesterol content of the niosomes, the hydrophilicity potential of the encapsulated compounds, and the preparation method of niosomes were the main factors affecting the mean volume diameter of the prepared vesicles. High physical stability of the niosomes prepared from Span 40 and Span 60 was demonstrated due to negligible size change of vesicles during 6 months storage at 4-8(°)C. In vivo studies showed that ST60/Chol 35 : 35 : 30 niosomes had more neuroprotective effects against cerebral ischemic injuries in male rats than free ascorbic acid.

Electrophysiological and neurochemical changes in the rat hippocampus after in vitro and in vivo treatments with cocaine

International Nuclear Information System (INIS)

Yasuda, R.P.

1986-01-01

The in vitro and in vivo effects of cocaine in the noradrenergic pathway in the rat hippocampus were examined. Although the blockade of [ 3 H]-norepinephrine-uptake by cocaine has been well-characterized in both the central and peripheral nervous systems, investigations characterizing the electrophysiological effects of cocaine in the central nervous system have been limited. The first part of this thesis examines the relationship between the ability of cocaine to potentiate the electrophysiological response to norepinephrine (NE) and the ability of cocaine to block noradrenergic high affinity uptake in rat hippocampal slices. The second part of this thesis examines the effects of the repeated administration of cocaine on noradrenergic pre- and postsynaptic function and receptors of the rat hippocampus. These studies demonstrate that after repeated administration of cocaine (10 mg/kg/day) for 8 and 14 days there is a 50% decrease in NE high affinity uptake in the rat hippocampus. This was accompanied by a 40% increase in a binding site for NE uptake inhibitors at 14 days. In contrast to these effects, there was no effect on β-adrenergic receptor number or the isoproterenol induced electrophysiological responsiveness in the rat hippocampus. The conclusion of these studies is that the repeated administration of cocaine has a greater effect on presynaptic targets in the noradrenergic system than on postsynaptic neurons

A physiologically based pharmacokinetic model for ethylene oxide in mouse, rat, and human.

Science.gov (United States)

Fennell, T R; Brown, C D

2001-06-15

Ethylene oxide (EO) is widely used as a gaseous sterilant and industrial intermediate and is a direct-acting mutagen and carcinogen. The objective of these studies was to develop physiologically based pharmacokinetic (PB-PK) models for EO to describe the exposure-tissue dose relationship in rodents and humans. We previously reported results describing in vitro and in vivo kinetics of EO metabolism in male and female F344 rats and B6C3F1 mice. These studies were extended by determining the kinetics of EO metabolism in human liver cytosol and microsomes. The results indicate enzymatically catalyzed GSH conjugation via cytosolic glutathione S-transferase (cGST) and hydrolysis via microsomal epoxide hydrolase (mEH) occur in both rodents and humans. The in vitro kinetic constants were scaled to account for cytosolic (cGST) and microsomal (mEH) protein content and incorporated into PB-PK descriptions for mouse, rat, and human. Flow-limited models adequately predicted blood and tissue EO levels, disposition, and elimination kinetics determined experimentally in rats and mice, with the exception of testis concentrations, which were overestimated. Incorporation of a diffusion-limited description for testis improved the ability of the model to describe testis concentrations. The model accounted for nonlinear increases in blood and tissue concentrations that occur in mice on exposure to EO concentrations greater than 200 ppm. Species differences are predicted in the metabolism and exposure-dose relationship, with a nonlinear relationship observed in the mouse as a result of GSH depletion. These models represent an essential step in developing a mechanistically based EO exposure-dose-response description for estimating human risk from exposure to EO. Copyright 2001 Academic Press.

Enhancing hippocampal blood flow after cerebral ischemia and vasodilating basilar arteries: in vivo and in vitro neuroprotective effect of antihypertensive DDPH

Directory of Open Access Journals (Sweden)

Li Sun

2015-01-01

Full Text Available 1-(2,6-Dimethylphenoxy-2-(3,4-dimethoxyphenylethylamino-propane hydrochloride (DDPH is a novel antihypertensive agent based on structural characteristics of mexiletine and verapamine. We investigated the effect of DDPH on vasodilatation and neuroprotection in a rat model of cerebral ischemia in vivo, and a rabbit model of isolated basilar arteries in vitro. Our results show that DDPH (10 mg/kg significantly increased hippocampal blood flow in vivo in cerebral ischemic rats, and exerted dose-dependent relaxation of isolated basilar arteries contracted by histamine or KCl in the in vitro rabbit model. DDPH (3 × 10 -5 M also inhibited histamine-stimulated extracellular calcium influx and intracellular calcium release. Our findings suggest that DDPH has a vasodilative effect both in vivo and in vitro, which mediates a neuroprotective effect on ischemic nerve tissue.

Mesenteric microcirculatory dysfunctions and translocation of indigenous bacteria in a rat model of strangulated small bowel obstruction

Directory of Open Access Journals (Sweden)

Fernando Luiz Zanoni

2009-01-01

Full Text Available PRUPOSE: Bacterial translocation has been shown to occur in critically ill patients after extensive trauma, shock, sepsis, or thermal injury. The present study investigates mesenteric microcirculatory dysfunctions, the bacterial translocation phenomenon, and hemodynamic/metabolic disturbances in a rat model of intestinal obstruction and ischemia. METHODS: Anesthetized (pentobarbital 50 mg/kg, i.p. male Wistar rats (250-350 g were submitted to intestinal obstruction or laparotomy without intestinal obstruction (Sham and were evaluated 24 hours later. Bacterial translocation was assessed by bacterial culture of the mesenteric lymph nodes (MLN, liver, spleen, and blood. Leukocyte-endothelial interactions in the mesenteric microcirculation were assessed by intravital microscopy, and P-selectin and intercellular adhesion molecule (ICAM-1 expressions were quantified by immunohistochemistry. Hematocrit, blood gases, lactate, glucose, white blood cells, serum urea, creatinine, bilirubin, and hepatic enzymes were measured. RESULTS: About 86% of intestinal obstruction rats presented positive cultures for E. coli in samples of the mesenteric lymph nodes, liver, and spleen, and 57% had positive hemocultures. In comparison to the Sham rats, intestinal obstruction induced neutrophilia and increased the number of rolling (~2-fold, adherent (~5-fold, and migrated leukocytes (~11-fold; this increase was accompanied by an increased expression of P-selectin (~2-fold and intercellular adhesion molecule-1 (~2-fold in the mesenteric microcirculation. Intestinal obstruction rats exhibited decreased PaCO2, alkalosis, hyperlactatemia, and hyperglycemia, and increased blood potassium, hepatic enzyme activity, serum urea, creatinine, and bilirubin. A high mortality rate was observed after intestinal obstruction (83% at 72 h vs. 0% in Sham rats. CONCLUSION: Intestinal obstruction and ischemia in rats is a relevant model for the in vivo study of mesenteric microcirculatory

Cardiovascular effects of a herbicide containing glufosinate and a surfactant: in vitro and in vivo analyses in rats.

Science.gov (United States)

Koyama, K; Koyama, K; Goto, K

1997-08-01

A herbicide, Basta (BASTA), containing glufosinate ammonium (GLA) as the main component and an anionic surfactant, sodium polyoxyethylene alkylether sulfate (AES), causes hemodynamic changes characterized by a decrease in total vascular resistance with an increase or a decrease in cardiac output in human acute oral poisoning. With a motivation based on these clinical observations, we tried to elucidate the exact component and its mode of action that is mostly responsible for the direct cardiovascular effects of this herbicide formulation, investigating the effects of BASTA, GLA, and AES independently on the cardiovascular system in rats in vitro and in vivo. In isolated right atria beating spontaneously in Krebs-Ringer's solution, BASTA and AES produced negative chronotropic responses in a concentration-dependent manner. In electrically driven isolated left atria, BASTA and AES produced positive inotropic responses concentration dependently but negative inotropic responses at extremely high concentrations. In aortic ring segments, BASTA and AES produced no vasoconstrictive effects but exerted significant vasodilative effects when the aortic ring was precontracted with phenylephrine. These in vitro responses caused by BASTA and AES occurred to a similar degree. On the other hand, the main component, GLA, produced no effects in isolated atria and aortas. In anesthetized rats, relatively low doses of BASTA and AES produced a decrease in blood pressure followed by a slight increase in heart rate, which was presumably due to baroreflex caused by the decrease in blood pressure. At an extremely high dose, BASTA and AES produced a decrease in blood pressure with a marked decrease in heart rate. These in vivo responses to BASTA and AES also occurred to a similar degree. In contrast, the main component, GLA, did not produce any effects on heart rate and blood pressure in anesthetized rats. From these results, we concluded that the effects of BASTA in our in vivo experiments

Dopamine denervation does not alter in vivo 3H-spiperone binding in rat striatum: implications for external imaging of dopamine receptors in Parkinson's disease

International Nuclear Information System (INIS)

Bennett, J.P. Jr.; Wooten, G.F.

1986-01-01

Striatal particulate preparations, both from rats with lesion-induced striatal dopamine (DA) loss and from some striatal dopamine (DA) loss and from some patients with Parkinson's disease, exhibit increased 3 H-neuroleptic binding, which is interpreted to be the mechanism of denervation-induced behavioral supersensitivity to dopaminergic compounds. After intravenous 3 H-spiperone ( 3 H-SP) administration to rats with unilateral nigral lesions, we found no differences in accumulation of total or particulate-bound 3 H-SP in dopamine-denervated compared with intact striata. 3 H-SP in vivo binds to less than 10% of striatal sites labeled by 3 H-SP incubated with striatal particulate preparations in vitro. Quantitative autoradiography of 3 H-SP binding to striatal sections in vitro also failed to reveal any effects of dopamine denervation. 3 H-SP bound to striatal sites in vivo dissociates more slowly than that bound to striatal particulate preparations labeled in vitro. Striatal binding properties of 3 H-SP administered in vivo are quite different from the same kinetic binding parameters estimated in vitro using crude membrane preparations of striatum. In addition, striatal binding of in vivo-administered 3H-SP is not affected by prior lesion of the substantia nigra, which results in profound ipsilateral striatal dopamine depletion. Thus, behavioral supersensitivity to dopaminergic compounds may not be associated with altered striatal binding properties for dopamine receptor ligands in vivo

An improved in vitro blood-brain barrier model: rat brain endothelial cells co-cultured with astrocytes.

Science.gov (United States)

Abbott, N Joan; Dolman, Diana E M; Drndarski, Svetlana; Fredriksson, Sarah M

2012-01-01

In vitro blood-brain barrier (BBB) models using primary cultured brain endothelial cells are important for establishing cellular and molecular mechanisms of BBB function. Co-culturing with BBB-associated cells especially astrocytes to mimic more closely the in vivo condition leads to upregulation of the BBB phenotype in the brain endothelial cells. Rat brain endothelial cells (RBECs) are a valuable tool allowing ready comparison with in vivo studies in rodents; however, it has been difficult to obtain pure brain endothelial cells, and few models achieve a transendothelial electrical resistance (TEER, measure of tight junction efficacy) of >200 Ω cm(2), i.e. the models are still relatively leaky. Here, we describe methods for preparing high purity RBECs and neonatal rat astrocytes, and a co-culture method that generates a robust, stable BBB model that can achieve TEER >600 Ω cm(2). The method is based on >20 years experience with RBEC culture, together with recent improvements to kill contaminating cells and encourage BBB differentiation.Astrocytes are isolated by mechanical dissection and cell straining and are frozen for later co-culture. RBECs are isolated from 3-month-old rat cortices. The brains are cleaned of meninges and white matter and enzymatically and mechanically dissociated. Thereafter, the tissue homogenate is centrifuged in bovine serum albumin to separate vessel fragments from other cells that stick to the myelin plug. The vessel fragments undergo a second enzyme digestion to separate pericytes from vessels and break down vessels into shorter segments, after which a Percoll gradient is used to separate capillaries from venules, arterioles, and single cells. To kill remaining contaminating cells such as pericytes, the capillary fragments are plated in puromycin-containing medium and RBECs grown to 50-60% confluence. They are then passaged onto filters for co-culture with astrocytes grown in the bottom of the wells. The whole procedure takes ∼2

Subthalamic hGAD65 Gene Therapy and Striatum TH Gene Transfer in a Parkinson’s Disease Rat Model

Science.gov (United States)

Zheng, Deyu; Jiang, Xiaohua; Zhao, Junpeng; Duan, Deyi; Zhao, Huanying; Xu, Qunyuan

2013-01-01

The aim of the present study is to detect a combination method to utilize gene therapy for the treatment of Parkinson’s disease (PD). Here, a PD rat model is used for the in vivo gene therapy of a recombinant adeno-associated virus (AAV2) containing a human glutamic acid decarboxylase 65 (rAAV2-hGAD65) gene delivered to the subthalamic nucleus (STN). This is combined with the ex vivo gene delivery of tyrosine hydroxylase (TH) by fibroblasts injected into the striatum. After the treatment, the rotation behavior was improved with the greatest efficacy in the combination group. The results of immunohistochemistry showed that hGAD65 gene delivery by AAV2 successfully led to phenotypic changes of neurons in STN. And the levels of glutamic acid and GABA in the internal segment of the globus pallidus (GPi) and substantia nigra pars reticulata (SNr) were obviously lower than the control groups. However, hGAD65 gene transfer did not effectively protect surviving dopaminergic neurons in the SNc and VTA. This study suggests that subthalamic hGAD65 gene therapy and combined with TH gene therapy can alleviate symptoms of the PD model rats, independent of the protection the DA neurons from death. PMID:23738148

Evaluation of 4,4'-diaminodiphenyl ether in the rat comet assay: Part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiative international validation study of in vivo rat alkaline comet assay.

Science.gov (United States)

Priestley, Catherine C; Walker, Joanne S; O'Donovan, Michael R; Doherty, Ann T

2015-07-01

As a part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiative international validation study of the in vivo rat alkaline comet assay, 4,4'-diaminodiphenyl ether (DPE), a known rodent genotoxic carcinogen, was tested in this laboratory. Sprague Dawley rats (7-9 weeks of age) were given three oral doses of DPE, 24 and 21 h apart and liver or stomach sampled 3h after the final dose. Under the conditions of the test, no increases in DNA damage in liver and stomach were observed with DPE (up to 200 mg/kg/day). A dose-dependent decrease in DNA migration, compared to vehicle controls, was noted for DPE in rat stomach. Further analysis is required to elucidate fully whether this decrease is a consequence of the mode of action or due to the toxicity of DPE. What is perhaps surprising is the inability of the comet assay to detect a known rat genotoxic carcinogen in liver. Further investigation is needed to clarify whether this apparent lack of response results from limited tissue exposure or metabolic differences between species. This finding highlights a need for careful consideration of study design when evaluating assay performance as a measure of in vivo genotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

A Novel Reporter Rat Strain That Conditionally Expresses the Bright Red Fluorescent Protein tdTomato.

Directory of Open Access Journals (Sweden)

Hiroyuki Igarashi

Full Text Available Despite the strength of the Cre/loxP recombination system in animal models, its application in rats trails that in mice because of the lack of relevant reporter strains. Here, we generated a floxed STOP tdTomato rat that conditionally expresses a red fluorescent protein variant (tdTomato in the presence of exogenous Cre recombinase. The tdTomato signal vividly visualizes neurons including their projection fibers and spines without any histological enhancement. In addition, a transgenic rat line (FLAME that ubiquitously expresses tdTomato was successfully established by injecting intracytoplasmic Cre mRNA into fertilized ova. Our rat reporter system will facilitate connectome studies as well as the visualization of the fine structures of genetically identified cells for long periods both in vivo and ex vivo. Furthermore, FLAME is an ideal model for organ transplantation research owing to improved traceability of cells/tissues.

Calcium absorption in rat large intestine in vivo: availability of dietary calcium

International Nuclear Information System (INIS)

Ammann, P.; Rizzoli, R.; Fleisch, H.

1986-01-01

Calcium absorption in the large intestine of the rat was investigated in vivo. After a single injection of 45 CaCl 2 into the cecum, 26.0 +/- 2.5% (mean +/- SE, n = 9) of the 45 CaCl 2 injected disappeared. This absorption was modulated by 1,25-dihydroxyvitamin D3, increased to 64.0 +/- 4.2% under a low-Ca diet, and increased under low-Pi diet. In contrast, when the difference of nonradioactive Ca in the cecal content and the feces was measured, only 4.1 +/- 4.6% (not significant) was absorbed. Secretion of intravenously injected 45 Ca into the lumen was small and not altered by any of the conditions tested. When cecum contents were placed into duodenal tied loops, 14 +/- 6.2% were absorbed in situ when 45 Ca was given orally, whereas when 45 Ca was directly added to the content 35.6 +/- 4.6% were absorbed (P less than 0.02). These results indicate that the large intestine has an important vitamin D-dependent Ca absorptive system detectable if 45 Ca is injected into the cecum. However, it is not effective in vivo because the Ca arriving in the large intestine appears to be no longer in an absorbable form

Expression of tenascin-C in a rat vocal fold injury model and its regulation of fibroblasts.

Science.gov (United States)

Li, Juan; Liu, Yiqiong; Wang, Yiming; Xu, Wen

2018-03-23

Tenascin-C (Tnc) is an extracellular matrix (ECM) glycoprotein that plays a vital role in wound healing and fibrotic disease. Tnc is highly upregulated soon after vocal fold injury, but its function in the vocal fold has not yet been defined. In this study, we investigated Tnc expression in a rat vocal fold injury model in vivo and its roles in fibroblasts in vitro. In vivo and in vitro. Tnc mRNA and protein expression levels were quantified on days 3, 7, 14, 28, and 56 after vocal fold injury in Sprague-Dawley rats. In vitro, immunocytochemistry, Western blot, and quantitative real-time polymerase chain reaction (qRT-PCR) analyses were performed in primary rat vocal fold fibroblasts following Tnc or transforming growth factor (TGF)-β1 stimulation to investigate the phenotypic effects. Tnc mRNA and protein expression was upregulated dramatically on days 3 and 7 after injury, and significant differences were observed by qRT-PCR (P vocal fold fibroblasts. Following incubation with Tnc for 72 hours, α-smooth muscle actin, collagen I, and fibronectin expression was significantly upregulated (P vocal fold fibroblast migration, transdifferentiation, and ECM protein synthesis in vitro. Tnc was induced by TGF-β1 in a SMAD3-dependent manner. Transient expression of Tnc is likely to promote regeneration, but its potential role in fibrosis requires further study. NA Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

In vivo incorporation of 1-14C-acetate into liver and plasma lipids of postnatally overfed rats

International Nuclear Information System (INIS)

Aust, L.; Noack, R.; Borchardt, M.; Akademie der Wissenschaften der DDR, Berlin-Buch. Forschungszentrum fuer Molekularbiologie und Medizin)

1982-01-01

Postnatal overnutrition due to breeding of rats in small nests (4 pups per dam) leads to distinct metabolic changes in later life stages even in conditions of ad libitum feeding. At an age of 5 months rats from small nests differ from those of large nests (14 pups per dam) in a significant higher level of liver triglycerides and cholesterol esters, whereas changes in plasma lipids concern only the increased cholesterol ester fraction. The relative distribution of in vivo incorporated 1- 14 C-acetate into liver lipids shows a higher moiety in the triglyceride fraction of animals from small nests but no changes of the relative distribution of activity among lipid fractions of plasma. These changes of lipid metabolism are discussed in relation to the development of an obese state of postnatally overfed animals. (author)

Effects of 1 alpha,25-Dihydroxyvitamin D-3 on Transporters and Enzymes of the Rat Intestine and Kidney In Vivo

NARCIS (Netherlands)

Chow, Edwin C. Y.; Sun, Huadong; Khan, Ansar A.; Groothuis, Geny M. M.; Pang, K. Sandy

1 alpha,25-Dihydroxyvitamin D-3 (1,25(OH)(2)D-3), the natural ligand of the vitamin D receptor (VDR), was found to regulate bile acid related transporters and enzymes directly and indirectly in the rat intestine and liver in vivo. The kidney is another VDR-rich target organ in which VDR regulation

Refinement of a model of repeated cerebrospinal fluid collection in conscious rats.

Science.gov (United States)

Amen, Eva Maria; Brecheisen, Muriel; Sach-Peltason, Lisa; Bergadano, Alessandra

2017-02-01

The cannulation of the cisterna magna in rats for in vivo sampling of cerebrospinal fluid serves as a valuable model for studying the delivery of new drugs into the central nervous system or disease models. It offers the advantages of repeated sampling without anesthesia-induced bias and using animals as their own controls. An established model was retrospectively reviewed for the outcomes and it was hypothesized that by refining the method, i.e. by (1) implementing pathophysiological-based anesthesia and analgesia, (2) using state-of-the-art peri-operative monitoring and supportive care, (3) increasing stability of the cement-cannula assembly, and (4) selecting a more adaptable animal strain, the outcome in using the model - quantified by peri-operative mortality, survival time and stability of the implant - could be improved and could enhance animal welfare. After refinement of the technique, peri-operative mortality decreased significantly (7 animals out of 73 compared with 4 out of 322; P = 0.001), survival time increased significantly (36 ± 14 days compared with 28 ± 18 days; P concept of Russell and Burch was successfully addressed and animal welfare was improved by (1) the reduction in the total number of animals needed as a result of lower mortality or fewer euthanizations due to technical failure, and frequent use of individual rats over a time frame; and (2) improving the scientific quality of the model.

Implanted, inductively-coupled, radiofrequency coils fabricated on flexible polymeric material: Application to in vivo rat brain MRI at 7 T

International Nuclear Information System (INIS)

Ginefri, J.C.; Poirier-Quinot, M.; Darrasse, L.; Rubin, A.; Tatoulian, M.; Woytasik, M.; Boumezbeur, F.; Djemai, B.; Lethimonnier, F.

2012-01-01

Combined with high-field MRI scanners, small implanted coils allow for high resolution imaging with locally improved SNR, as compared to external coils. Small flexible implantable coils dedicated to in vivo MRI of the rat brain at 7 T were developed. Based on the Multi-turn Transmission Line Resonator design, they were fabricated with a Teflon substrate using copper micro-molding process and a specific metal-polymer adhesion treatment. The implanted coils were made biocompatible by Polydimethylsiloxane (PDMS) encapsulation. The use of low loss tangent material achieves low dielectric losses within the substrate and the use of the PDMS layer reduces the parasitic coupling with the surrounding media. An implanted coil was implemented in a 7 T MRI system using inductive coupling and a dedicated external pick-up coil for signal transmission. In vivo images of the rat brain acquired with in plane resolution of (150 μm) 2 thanks to the implanted coil revealed high SNR near the coil, allowing for the visualization of fine cerebral structures. (authors)

Halofuginone Inhibits Angiogenesis and Growth in Implanted Metastatic Rat Brain Tumor Model-an MRI Study

Directory of Open Access Journals (Sweden)

Rinat Abramovitch

2004-09-01

Full Text Available Tumor growth and metastasis depend on angiogenesis; therefore, efforts are made to develop specific angiogenic inhibitors. Halofuginone (HF is a potent inhibitor of collagen type α1(I. In solid tumor models, HF has a potent antitumor and antiangiogenic effect in vivo, but its effect on brain tumors has not yet been evaluated. By employing magnetic resonance imaging (MRI, we monitored the effect of HF on tumor progression and vascularization by utilizing an implanted malignant fibrous histiocytoma metastatic rat brain tumor model. Here we demonstrate that treatment with HF effectively and dose-dependently reduced tumor growth and angiogenesis. On day 13, HF-treated tumors were fivefold smaller than control (P < .001. Treatment with HF significantly prolonged survival of treated animals (142%; P = .001. In HF-treated rats, tumor vascularization was inhibited by 30% on day 13 and by 37% on day 19 (P < .05. Additionally, HF treatment inhibited vessel maturation (P = .03. Finally, in HF-treated rats, we noticed the appearance of a few clusters of satellite tumors, which were distinct from the primary tumor and usually contained vessel cores. This phenomenon was relatively moderate when compared to previous reports of other antiangiogenic agents used to treat brain tumors. We therefore conclude that HF is effective for treatment of metastatic brain tumors.

ENU mutagenesis to generate genetically modified rat models.

Science.gov (United States)

van Boxtel, Ruben; Gould, Michael N; Cuppen, Edwin; Smits, Bart M G

2010-01-01

The rat is one of the most preferred model organisms in biomedical research and has been extremely useful for linking physiology and pathology to the genome. However, approaches to genetically modify specific genes in the rat germ line remain relatively scarce. To date, the most efficient approach for generating genetically modified rats has been the target-selected N-ethyl-N-nitrosourea (ENU) mutagenesis-based technology. Here, we describe the detailed protocols for ENU mutagenesis and mutant retrieval in the rat model organism.

SU-E-I-34: Intermittent Low- and High-Dose Ethanol Exposure Alters Neurochemical Responses in Adult Rat Brain: An Ex Vivo 1H NMR Spectroscopy at 11.7 T

Energy Technology Data Exchange (ETDEWEB)

Lee, Do-Wan; Kim, Sang-Young; Song, Kyu-Ho; Choe, Bo-Young [Department of Biomedical Engineering, and Research Institute of Biomedical Engineering, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)

2014-06-01

Purpose: The first goal of this study was to determine the influence of the dose-dependent effects of intermittent ethanol intoxication on cerebral neurochemical responses among sham controls and low- and high-dose-ethanol-exposed rats with ex vivo high-resolution spectra. The second goal of this study was to determine the correlations between the metabolite-metabolite levels (pairs-of-metabolite levels) from all of the individual data from the frontal cortex of the intermittent ethanol-intoxicated rats. Methods: Eight-week-old male Wistar rats were divided into 3 groups. Twenty rats in the LDE (n = 10) and the HDE (n = 10) groups received ethanol doses of 1.5 g/kg and 2.5 g/kg, respectively, through oral gavage every 8-h for 4 days. At the end of the 4-day intermittent ethanol exposure, one-dimensional ex vivo 500-MHz proton nuclear magnetic resonance spectra were acquired from 30 samples of the frontal cortex region (from the 3 groups). Results: Normalized total-N-acetylaspartate (tNAA: NAA + NAAG [N-acetylaspartyl-glutamate]), gamma-aminobutyric acid (GABA), and glutathione (GSH) levels were significantly lower in the frontal cortex of the HDE-exposed rats than that of the LDE-exposed rats. Moreover, compared to the CNTL group, the LDE rats exhibited significantly higher normalized GABA levels. The 6 pairs of normalized metabolite levels were positively (+) or negatively (−) correlated in the rat frontal cortex as follows: tNAA and GABA (+), tNAA and Aspartate (Asp) (−), myo-Inositol (mIns) and Asp (−), mIns and Alanine (+), mIns and Taurine (+), and mIns and tNAA (−). Conclusion: Our results suggested that repeated intermittent ethanol intoxication might result in neuronal degeneration and dysfunction, changes in the rate of GABA synthesis, and oxidative stress in the rat frontal cortex. Our ex vivo 1H high-resolution-magic angle spinning nuclear magnetic resonance spectroscopy results suggested some novel metabolic markers for the dose

SU-E-I-34: Intermittent Low- and High-Dose Ethanol Exposure Alters Neurochemical Responses in Adult Rat Brain: An Ex Vivo 1H NMR Spectroscopy at 11.7 T

International Nuclear Information System (INIS)

Lee, Do-Wan; Kim, Sang-Young; Song, Kyu-Ho; Choe, Bo-Young

2014-01-01

Purpose: The first goal of this study was to determine the influence of the dose-dependent effects of intermittent ethanol intoxication on cerebral neurochemical responses among sham controls and low- and high-dose-ethanol-exposed rats with ex vivo high-resolution spectra. The second goal of this study was to determine the correlations between the metabolite-metabolite levels (pairs-of-metabolite levels) from all of the individual data from the frontal cortex of the intermittent ethanol-intoxicated rats. Methods: Eight-week-old male Wistar rats were divided into 3 groups. Twenty rats in the LDE (n = 10) and the HDE (n = 10) groups received ethanol doses of 1.5 g/kg and 2.5 g/kg, respectively, through oral gavage every 8-h for 4 days. At the end of the 4-day intermittent ethanol exposure, one-dimensional ex vivo 500-MHz proton nuclear magnetic resonance spectra were acquired from 30 samples of the frontal cortex region (from the 3 groups). Results: Normalized total-N-acetylaspartate (tNAA: NAA + NAAG [N-acetylaspartyl-glutamate]), gamma-aminobutyric acid (GABA), and glutathione (GSH) levels were significantly lower in the frontal cortex of the HDE-exposed rats than that of the LDE-exposed rats. Moreover, compared to the CNTL group, the LDE rats exhibited significantly higher normalized GABA levels. The 6 pairs of normalized metabolite levels were positively (+) or negatively (−) correlated in the rat frontal cortex as follows: tNAA and GABA (+), tNAA and Aspartate (Asp) (−), myo-Inositol (mIns) and Asp (−), mIns and Alanine (+), mIns and Taurine (+), and mIns and tNAA (−). Conclusion: Our results suggested that repeated intermittent ethanol intoxication might result in neuronal degeneration and dysfunction, changes in the rate of GABA synthesis, and oxidative stress in the rat frontal cortex. Our ex vivo 1H high-resolution-magic angle spinning nuclear magnetic resonance spectroscopy results suggested some novel metabolic markers for the dose

Oxidative stress of crystalline lens in rat menopausal model

OpenAIRE

Acer, Semra; Pekel, Gökhan; Küçükatay, Vural; Karabulut, Aysun; Yağcı, Ramazan; Çetin, Ebru Nevin; Akyer, Şahika Pınar; Şahin, Barbaros

2016-01-01

ABSTRACT Purpose: To evaluate lenticular oxidative stress in rat menopausal models. Methods: Forty Wistar female albino rats were included in this study. A total of thirty rats underwent oophorectomy to generate a menopausal model. Ten rats that did not undergo oophorectomy formed the control group (Group 1). From the rats that underwent oophorectomy, 10 formed the menopause control group (Group 2), 10 were administered a daily injection of methylprednisolone until the end of the study (Gro...

In vivo and in vitro effects of lysine clonixinate on nitric oxide synthase in LPS-treated and untreated rat lung preparations.

Science.gov (United States)

Franchi, A M; Di Girolamo, G; Farina, M; de los Santos, A R; Martí, M L; Gimeno, M A

2001-04-01

Recent studies have shown that some nonsteroidal antiinflammatory drugs (NSAIDS) inhibited the inducible NO synthase (iNOS) without direct effect on the catalytic activity of this enzyme. This study was conducted to investigate the in vitro and in vivo effects of lysine clonixinate (LC) and indomethacin (INDO) on NOS activity in rat lung preparation. LC is a drug with antiinflammatory, antipyretic, and analgesic action. In the in vitro experiments, rats were injected with saline or lipopolysaccharide (LPS) and killed 6 h after treatment. Lung preparations were incubated with LC at 2.3 x 10(-5) M or 3.8 x 10(-5) M. The minimum concentration did not modify NOS activity in control or LPS-treated rats but the maximum dose inhibited increased NO production induced by LPS. Furthermore, INDO at 10(-6) M had no effect on enzymatic activity in control or LPS-treated rats. In the in vivo experiments, 40 mg/kg of LC were injected ip. Such a dose did not affect basal production of NO. When LC and LPS were injected simultaneously 6 h before sacrifice, a significant decrease in LPS-induced NOS activity was observed. INDO 10 mg/kg injected in control animals had no effect on NOS activity and did not block LPS induced stimulation of NO production when injected simultaneously. Finally, when LC (40 mg/kg) was injected 3 h after LPS, the enzymatic activity remained unchanged. Expression of iNOS was detected by Western blotting in rats treated with LPS plus 4, 10, 20, and 40 mg/kg of LC. The lowest dose was the only one showing no effect on LPS-induced increase of iNOS. In short, LC is a NSAID with inhibitory action on the expression of LPS-induced NOS, effect that was not seen with INDO in our experimental conditions. Copyright 2001 Academic Press.

In vivo pretreatment of Eudrilus eugeniae powder attenuates β-adrenoceptor toxicity mediated by isoproterenol in rat model

OpenAIRE

Jaganathan Anitha; Kadarkarai Murugan; Akon Higuchi; Abdullah A. Alarfaj; Murugan A. Munusamy; Giovanni Benelli

2016-01-01

The present study was designed to discover the potential cardioprotective function of earthworm powder (EWP) extracted from Eudrilus eugeniae on isoproterenol (ISO)-induced myocardial infarction in male Wistar rats. The rats were divided into four groups, with six rats in each group. Certain rats were pretreated with EWP (200 mg/kg bwt) (Group III), and a myocardial infarction was then induced by subcutaneous injection of ISO (85 mg/kg bwt) (Group II). Oral pretreatment of 200 mg/kg bwt of EW...

Unilateral lesion of dorsal hippocampus in adult rats impairs contralateral long-term potentiation in vivo and spatial memory in the early postoperative phase.

Science.gov (United States)

Li, Hongjie; Wu, Xiaoyan; Bai, Yanrui; Huang, Yan; He, Wenting; Dong, Zhifang

2012-05-01

It is well documented that bilateral hippocampal lesions or unilateral hippocampal lesion at birth causes impairment of contralateral LTP and long-term memory. However, effects of unilateral hippocampal lesion in adults on contralateral in vivo LTP and memory are not clear. We here examined the influence of unilateral electrolytic dorsal hippocampal lesion in adult rats on contralateral LTP in vivo and spatial memory during different postoperative phases. We found that acute unilateral hippocampal lesion had no effect on contralateral LTP. However, contralateral LTP was impaired at 1 week after lesion, and was restored to the control level at postoperative week 4. Similarly, spatial memory was also impaired at postoperative week 1, and was restored at postoperative week 4. In addition, the rats at postoperative week 1 showed stronger spatial exploratory behavior in a novel open-field environment. The sham operation had no effects on contralateral LTP, spatial memory and exploration at either postoperative week 1 or week 4. These results suggest that unilateral dorsal hippocampal lesion in adult rats causes transient contralateral LTP impairment and spatial memory deficit. Copyright © 2012 Elsevier B.V. All rights reserved.

Elucidation of Arctigenin Pharmacokinetics and Tissue Distribution after Intravenous, Oral, Hypodermic and Sublingual Administration in Rats and Beagle Dogs: Integration of In Vitro and In Vivo Findings.

Science.gov (United States)

Li, Jie; Li, Xin; Ren, Yu-Shan; Lv, Yuan-Yuan; Zhang, Jun-Sheng; Xu, Xiao-Li; Wang, Xian-Zhen; Yao, Jing-Chun; Zhang, Gui-Min; Liu, Zhong

2017-01-01

Although arctigenin ( AG ) has diverse bioactivities, such as anti-oxidant, anti-inflammatory, anti-cancer, immunoregulatory and neuroprotective activities, its pharmacokinetics have not been systematically evaluated. The purpose of this work was to identify the pharmacokinetic properties of AG via various experiments in vivo and in vitro . In this research, rats and beagle dogs were used to investigate the PK (pharmacokinetics, PK) profiles of AG with different drug-delivery manners, including intravenous (i.v), hypodermic injection (i.h), and sublingual (s.l) administration. The data shows that AG exhibited a strong absorption capacity in both rats and beagle dogs (absorption rate 100%), and a strong elimination ability ( t 1/2 beagle dog (25.9 ± 3.24%) > rat (15.7 ± 9%) > monkey (3.69 ± 0.12%). This systematic investigation of pharmacokinetic profiles of arctigenin (AG) in vivo and in vitro is worthy of further exploration.

Characterization of rat lung ICAM-1

DEFF Research Database (Denmark)

Beck-Schimmer, B; Schimmer, R C; Schmal, H

1998-01-01

studies, rat pulmonary artery endothelial cells (RPAEC), rat alveolar macrophages and aortic rings were stimulated (as described below) and evaluated for ICAM-1 expression. TREATMENT: RPAEC and macrophages were stimulated with lipopolysaccharide (LPS) and recombinant murine tumour necrosis factor alpha...... peaked at 4 h, while lung ICAM- I protein peaked at 6 h. CONCLUSIONS: Quantitation of ICAM-1 expression in vitro and in vivo suggests that ICAM-1 plays a central role in two lung inflammatory models. Furthermore, lung ICAM-1 upregulation involves at least two cell types: vascular endothelial cells...

Nicotine affects rat Leydig cell function in vivo and vitro via down-regulating some key steroidogenic enzyme expressions.

Science.gov (United States)

Guo, Xiaoling; Wang, Huang; Wu, Xiaolong; Chen, Xianwu; Chen, Yong; Guo, Jingjing; Li, Xiaoheng; Lian, Qingquan; Ge, Ren-Shan

2017-12-01

Nicotine is consumed largely as a component of cigarettes and has a potential effect on pubertal development of Leydig cells in males. To investigate its effects, 49-day-old male Sprague Dawley rats received intraperitoneal injections of nicotine (0.5 or 1 mg/kg/day) for 2 weeks and immature Leydig cells were isolated from the testes of 35-day-old rats and treated with nicotine (0.05-50 μM). Serum hormones, Leydig cell number and related gene expression levels after in vivo treatment were determined and medium androgen levels were measured and cell cycle, apoptosis, mitochondrial membrane potential (△Ψm), and reactive oxygen species (ROS) of Leydig cells after in vitro treatment were measured. In vivo exposure to nicotine lowered serum luteinizing hormone, follicle stimulating hormone, and testosterone levels and reduced Leydig cell number and gene expression levels. Nicotine in vitro inhibited androgen production in Leydig cells by downregulating the expression levels of P450 cholesterol side cleavage enzyme, 3β-hydroxysteroid dehydrogenase 1, and steroidogenic factor 1 at different concentration ranges. In conclusion, nicotine disrupts Leydig cell steroidogenesis during puberty possibly via down-regulating some key steroidogenic enzyme expressions. Copyright © 2017. Published by Elsevier Ltd.

N-Methyl-D-aspartate Receptor Excessive Activation Inhibited Fetal Rat Lung Development In Vivo and In Vitro

Directory of Open Access Journals (Sweden)

Zhengchang Liao

2016-01-01

Full Text Available Background. Intrauterine hypoxia is a common cause of fetal growth and lung development restriction. Although N-methyl-D-aspartate receptors (NMDARs are distributed in the postnatal lung and play a role in lung injury, little is known about NMDAR’s expression and role in fetal lung development. Methods. Real-time PCR and western blotting analysis were performed to detect NMDARs between embryonic days (E 15.5 and E21.5 in fetal rat lungs. NMDAR antagonist MK-801’s influence on intrauterine hypoxia-induced retardation of fetal lung development was tested in vivo, and NMDA’s direct effect on fetal lung development was observed using fetal lung organ culture in vitro. Results. All seven NMDARs are expressed in fetal rat lungs. Intrauterine hypoxia upregulated NMDARs expression in fetal lungs and decreased fetal body weight, lung weight, lung-weight-to-body-weight ratio, and radial alveolar count, whereas MK-801 alleviated this damage in vivo. In vitro experiments showed that NMDA decreased saccular circumference and area per unit and downregulated thyroid transcription factor-1 and surfactant protein-C mRNA expression. Conclusions. The excessive activation of NMDARs contributed to hypoxia-induced fetal lung development retardation and appropriate blockade of NMDAR might be a novel therapeutic strategy for minimizing the negative outcomes of prenatal hypoxia on lung development.

- In vivo monitoring of 5-FU

OpenAIRE

Lucas, Susanne

2010-01-01

The aim of the present study was to establish the in vivo-monitoring of the enrichment of 5-FU liposomes in liver and liver metastases by MRI methods. Relative signal intensities of liver and tumor tissue were determined. After sacrifying animals concentrations of 5-FU and it´s active intracellular metabolite M3 were measured by HPLC techniques. We used CC531 adenocarcinoma in the liver of WAG/Rij rats as a standardized liver tumor model in our investigatio...

Dietary fibers from mushroom sclerotia. 4. In vivo mineral absorption using ovariectomized rat model.

Science.gov (United States)

Wong, Ka-Hing; Katsumata, Shin-Ichi; Masuyama, Ritsuko; Uehara, Mariko; Suzuki, Kazuharu; Cheung, Peter C K

2006-03-08

The effect of three novel dietary fibers (DFs) prepared from mushroom sclerotia, namely, Pleurotus tuber-regium, Polyporus rhinocerus, and Wolfiporia cocos, on calcium and magnesium absorption was evaluated in ovariectomized (OVX) rats fed with sclerotial DF based and low Ca (0.3%) diets for 14 days. The animals in the W. cocos DF diet group possessed significantly (p cocos DF group were also significantly (p cocos DF could improve the overall Ca and Mg absorptions of the OVX rats fed a low Ca diet. The potential use of sclerotial DFs as a functional food ingredient for enhancing mineral absorption is also discussed.

Chronic massive rotator cuff tear in rats: in vivo evaluation of muscle force and three-dimensional histologic analysis.

Science.gov (United States)

Ditsios, Konstantinos; Boutsiadis, Achilleas; Kapoukranidou, Dorothea; Chatzisotiriou, Athanasios; Kalpidis, Ioannis; Albani, Maria; Christodoulou, Anastasios

2014-12-01

Massive rotator cuff tear repair is frequently complicated by unsatisfactory clinical results due to possible tendon retraction, muscle atrophy, and fatty degeneration. The objective of this study was the development of a chronic massive tear in a rat model and the evaluation of the muscle force in vivo and of the histologic changes in a 3- dimensional manner. To simulate massive rotator cuff tears, both the supraspinatus (SS) and the infraspinatus (IS) tendons were surgically detached from the right humerus of 15 male adult Sprague-Dawley rats. Twelve weeks postoperatively, all animals underwent isometric tension recordings of both the SS and IS muscles. Histologic analysis and image deconvolution processing were performed to estimate the presence and the distribution of atrophy in 3 dimensions. An overall 30% and 35% reduction in muscle force of the SS and IS muscles, respectively, was observed compared with the left uninjured shoulder (P muscle groups. These results show that functional impairment of SS and IS muscles after chronic massive tendon tears could be attributed to the decrease in muscle force production during their repair on the greater tuberosity and, second, to the comparatively greater degeneration of their dorsal part. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Measurement of renal blood flow by 131I-labelled sodium iodohippurate imaging in a rat model of herpes encephalitis

International Nuclear Information System (INIS)

Cleator, G.M.; Klapper, P.E.; Lewis, A.G.; Sharma, H.L.; Smith, A.M.; Manchester Univ.

1990-01-01

Renal blood flow was assessed qualitatively over a 30 min period in a rat model of herpes encephalitis by extra-renal scintigraphic imaging following the injection of 131 I-labelled sodium iodohippurate. No significant differences were observed for renal blood flow in either kidney between (or within) infected and control groups. Our data suggest that kidney function is not compromised in this animal model of encephalitis. The results are discussed in the context of the development of a non-invasive protocol for the in vivo diagnosis of herpes encephalitis. (orig.)

Rosuvastatin reduces neointima formation in a rat model of balloon injury

Directory of Open Access Journals (Sweden)

Preusch MR

2010-11-01

Full Text Available Abstract Background Processes of restenosis, following arterial injury, are complex involving different cell types producing various cytokines and enzymes. Among those enzymes, smooth muscle cell-derived matrix metalloproteinases (MMPs are thought to take part in cell migration, degrading of extracellular matrix, and neointima formation. MMP-9, also known as gelatinase B, is expressed immediately after vascular injury and its expression and activity can be inhibited by statins. Using an established in vivo model of vascular injury, we investigated the effect of the HMG-CoA reductase inhibitor rosuvastatin on MMP-9 expression and neointima formation. Materials and methods 14-week old male Sprague Dawley rats underwent balloon injury of the common carotid artery. Half of the animals received rosuvastatin (20 mg/kg body weight/day via oral gavage, beginning 3 days prior to injury. Gelatinase activity and neointima formation were analyzed 3 days and 14 days after balloon injury, respectively. 14 days after vascular injury, proliferative activity was assessed by staining for Ki67. Results After 14 days, animals in the rosuvastatin group showed a decrease in total neointima formation (0.194 ± 0.01 mm2 versus 0.124 ± 0.02 mm2, p Conclusions Rosuvastatin attenuates neointima formation without affecting early MMP-9 activity in a rat model of vascular injury.

Niosomes of Ascorbic Acid and α-Tocopherol in the Cerebral Ischemia-Reperfusion Model in Male Rats

Directory of Open Access Journals (Sweden)

Jaleh Varshosaz

2014-01-01

Full Text Available The objective of the present study was to prepare a stable iv injectable formulation of ascorbic acid and α-tocopherol in preventing the cerebral ischemia. Different niosomal formulations were prepared by Span and Tween mixed with cholesterol. The physicochemical characteristics of niosomal formulations were evaluated in vitro. For in vivo evaluation, the rats were made ischemic by middle cerebral artery occlusion model for 30 min and the selected formulation was used for determining its neuroprotective effect against cerebral ischemia. Neuronal damage was evaluated by optical microscopy and transmission electron microscopy. The encapsulation efficiency of ascorbic acid was increased to more than 84% by remote loading method. The cholesterol content of the niosomes, the hydrophilicity potential of the encapsulated compounds, and the preparation method of niosomes were the main factors affecting the mean volume diameter of the prepared vesicles. High physical stability of the niosomes prepared from Span 40 and Span 60 was demonstrated due to negligible size change of vesicles during 6 months storage at 4–8°C. In vivo studies showed that ST60/Chol 35 : 35 : 30 niosomes had more neuroprotective effects against cerebral ischemic injuries in male rats than free ascorbic acid.

The translocator protein radioligand 18F-DPA-714 monitors antitumor effect of erufosine in a rat 9L intracranial glioma model

International Nuclear Information System (INIS)

Awde, Ali R.; Boisgard, Raphael; Theze, Benoit; Dubois, Albertine; Zheng, Jinzi; Winkeler, Alexandra; Dolle, Frederic; Jacobs, Andreas H.; Tavitian, Bertrand

2013-01-01

On the one hand, the translocator protein (TSPO) radioligand N,N-diethyl-2-(2-(4-(2- 18 F-fluoroethoxy)phenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl)acetamide ( 18 F-DPA-714) has been suggested to serve as an alternative radiotracer to image human glioma, and on the other hand the alkyl-phosphocholine erufosine (ErPC3) has been reported to induce apoptosis in otherwise highly apoptosis resistant glioma cell lines. The induction of apoptosis by ErPC3 requires TSPO, a mitochondrial membrane protein highly expressed in malignant gliomas. In this preclinical study, we monitored the effect of ErPC3 treatment in vivo using 18 F-DPA-714 PET. Methods: In vitro studies investigated the antitumor effect of ErPC3 in 9L rat gliosarcoma cells. In vivo, glioma-bearing rats were imaged with 18 F-DPA-714 for the time of treatment. Results: A significant decrease in 9L cell proliferation and viability and a significant increase in apoptosis and caspase-3 activation were demonstrated on ErPC3 treatment in cell culture. In the rat model, ErPC3 administration resulted in significant changes in 18 F-DPA-714 tumor uptake over the course of the treatment. Immunohistochemistry revealed reduced tumor volume and increased cell death in ErPC3-treated animals accompanied by infiltration of the tumor core by CD11b-positive micro-glia/macrophages and glial fibrillary acidic protein-positive astrocytes. Conclusion: Our findings demonstrate a potent antitumor effect of ErPC3 in vitro, in vivo, and ex vivo. PET imaging of TSPO expression using 18 F-DPA-714 allows effective monitoring and quantification of disease progression and response to ErPC3 therapy in intracranial 9L gliomas. (authors)

Effects of γ-Aminobutyric acid transporter 1 inhibition by tiagabine on brain glutamate and γ-Aminobutyric acid metabolism in the anesthetized rat In vivo.

Science.gov (United States)

Patel, Anant B; de Graaf, Robin A; Rothman, Douglas L; Behar, Kevin L

2015-07-01

γ-Aminobutyric acid (GABA) clearance from the extracellular space after release from neurons involves reuptake into terminals and astrocytes through GABA transporters (GATs). The relative flows through these two pathways for GABA released from neurons remains unclear. This study determines the effect of tiagabine, a selective inhibitor of neuronal GAT-1, on the rates of glutamate (Glu) and GABA metabolism and GABA resynthesis via the GABA-glutamine (Gln) cycle. Halothane-anesthetized rats were administered tiagabine (30 mg/kg, i.p.) and 45 min later received an intravenous infusion of either [1,6-(13)C2]glucose (in vivo) or [2-(13)C]acetate (ex vivo). Nontreated rats served as controls. Metabolites and (13)C enrichments were measured with (1)H-[(13)C]-nuclear magnetic resonance spectroscopy and referenced to their corresponding endpoint values measured in extracts from in situ frozen brain. Metabolic flux estimates of GABAergic and glutamatergic neurons were determined by fitting a metabolic model to the (13)C turnover data measured in vivo during [1,6-(13)C2]glucose infusion. Tiagabine-treated rats were indistinguishable (P > 0.05) from controls in tissue amino acid levels and in (13)C enrichments from [2-(13)C]acetate. Tiagabine reduced average rates of glucose oxidation and neurotransmitter cycling in both glutamatergic neurons (↓18%, CMR(glc(ox)Glu): control, 0.27 ± 0.05 vs. tiagabine, 0.22 ± 0.04 µmol/g/min; ↓11%, V(cyc(Glu-Gln)): control 0.23 ± 0.05 vs. tiagabine 0.21 ± 0.04 µmol/g/min and GABAergic neurons (↓18-25%, CMR(glc(ox)GABA): control 0.09 ± 0.02 vs. tiagabine 0.07 ± 0.03 µmol/g/min; V(cyc(GABA-Gln)): control 0.08 ± 0.02 vs. tiagabine 0.07 ± 0.03 µmol/g/min), but the changes in glutamatergic and GABAergic fluxes were not significant (P > 0.10). The results suggest that any reduction in GABA metabolism by tiagabine might be an indirect response to reduced glutamatergic drive rather than direct compensatory effects. © 2015 Wiley

Characterization of pioglitazone cyclodextrin complexes: Molecular modeling to in vivo evaluation

Directory of Open Access Journals (Sweden)

Dinesh M Bramhane

2016-01-01

Full Text Available Aims: The objective of present study was to study the influence of different β-cyclodextrin derivatives and different methods of complexation on aqueous solubility and consequent translation in in vivo performance of Pioglitazone (PE. Material and Methods: Three cyclodextrins: β-cyclodextrin (BCD, hydroxypropyl-β-cyclodextrin (HPBCD and Sulfobutylether-7-β-cyclodextrin (SBEBCD were employed in preparation of 1:1 Pioglitazone complexes by three methods viz. co-grinding, kneading and co-evaporation. Complexation was confirmed by phase solubility, proton NMR, Fourier Transform Infrared spectroscopy, Differential Scanning Calorimetry (DSC and X-Ray diffraction (XRD. Mode of complexation was investigated by molecular dynamic studies. Pharmacodynamic study of blood glucose lowering activity of PE complexes was performed in Alloxan induced diabetic rat model. Results: Aqueous solubility of PE was significantly improved in presence of cyclodextrin. Apparent solubility constants were observed to be 254.33 M–1 for BCD-PE, 737.48 M–1 for HPBCD-PE and 5959.06 M–1 for SBEBCD-PE. The in silico predictions of mode of inclusion were in close agreement with the experimental proton NMR observation. DSC and XRD demonstrated complete amorphization of crystalline PE upon inclusion. All complexes exhibited >95% dissolution within 10 min compared to drug powder that showed <40% at the same time. Marked lowering of blood glucose was recorded for all complexes. Conclusion: Complexation of PE with different BCD significantly influenced its aqueous solubility, improved in vitro dissolution and consequently translated into enhanced pharmacodynamic activity in rats

A simple, rapid, and sensitive system for the evaluation of anti-viral drugs in rats

Energy Technology Data Exchange (ETDEWEB)

Li, Xiaoguang [Tohoku University Graduate School of Medicine, Department of Internal Medicine/Division of Emerging Infectious Diseases, Sendai 980-8575 (Japan); Department of Medical Microbiology, Harbin Medical University, Harbin 150086 (China); Center for AIDS Research, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811 (Japan); Qian, Hua [Tohoku University Graduate School of Medicine, Department of Internal Medicine/Division of Emerging Infectious Diseases, Sendai 980-8575 (Japan); Center for AIDS Research, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811 (Japan); Miyamoto, Fusako [Tohoku University Graduate School of Medicine, Department of Internal Medicine/Division of Emerging Infectious Diseases, Sendai 980-8575 (Japan); Naito, Takeshi [Laboratory of Virus Control, Institute for Virus Research, Kyoto University, 53 Kawaramachi, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Kawaji, Kumi [Tohoku University Graduate School of Medicine, Department of Internal Medicine/Division of Emerging Infectious Diseases, Sendai 980-8575 (Japan); Kajiwara, Kazumi [Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan); JST Innovation Plaza Kyoto, Japan Science and Technology Agency, Nishigyo-ku, Kyoto 615-8245 (Japan); Hattori, Toshio [Tohoku University Graduate School of Medicine, Department of Internal Medicine/Division of Emerging Infectious Diseases, Sendai 980-8575 (Japan); Matsuoka, Masao [Laboratory of Virus Control, Institute for Virus Research, Kyoto University, 53 Kawaramachi, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Watanabe, Kentaro; Oishi, Shinya; Fujii, Nobutaka [Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan); and others

2012-07-27

Highlights: Black-Right-Pointing-Pointer We established a novel, simple and rapid in vivo system for evaluation of anti-HIV-1 drugs with rats. Black-Right-Pointing-Pointer The system may be applicable for other antiviral drugs, and/or useful for initial screening in vivo. Black-Right-Pointing-Pointer In this system, TRI-1144 displayed the most potent anti-HIV-1 activity in vivo. -- Abstract: The lack of small animal models for the evaluation of anti-human immunodeficiency virus type 1 (HIV-1) agents hampers drug development. Here, we describe the establishment of a simple and rapid evaluation system in a rat model without animal infection facilities. After intraperitoneal administration of test drugs to rats, antiviral activity in the sera was examined by the MAGI assay. Recently developed inhibitors for HIV-1 entry, two CXCR4 antagonists, TF14016 and FC131, and four fusion inhibitors, T-20, T-20EK, SC29EK, and TRI-1144, were evaluated using HIV-1{sub IIIB} and HIV-1{sub BaL} as representative CXCR4- and CCR5-tropic HIV-1 strains, respectively. CXCR4 antagonists were shown to only possess anti-HIV-1{sub IIIB} activity, whereas fusion inhibitors showed both anti-HIV-1{sub IIIB} and anti-HIV-1{sub BaL} activities in rat sera. These results indicate that test drugs were successfully processed into the rat sera and could be detected by the MAGI assay. In this system, TRI-1144 showed the most potent and sustained antiviral activity. Sera from animals not administered drugs showed substantial anti-HIV-1 activity, indicating that relatively high dose or activity of the test drugs might be needed. In conclusion, the novel rat system established here, 'phenotypic drug evaluation', may be applicable for the evaluation of various antiviral drugs in vivo.

A simple, rapid, and sensitive system for the evaluation of anti-viral drugs in rats

International Nuclear Information System (INIS)

Li, Xiaoguang; Qian, Hua; Miyamoto, Fusako; Naito, Takeshi; Kawaji, Kumi; Kajiwara, Kazumi; Hattori, Toshio; Matsuoka, Masao; Watanabe, Kentaro; Oishi, Shinya; Fujii, Nobutaka

2012-01-01

Highlights: ► We established a novel, simple and rapid in vivo system for evaluation of anti-HIV-1 drugs with rats. ► The system may be applicable for other antiviral drugs, and/or useful for initial screening in vivo. ► In this system, TRI-1144 displayed the most potent anti-HIV-1 activity in vivo. -- Abstract: The lack of small animal models for the evaluation of anti-human immunodeficiency virus type 1 (HIV-1) agents hampers drug development. Here, we describe the establishment of a simple and rapid evaluation system in a rat model without animal infection facilities. After intraperitoneal administration of test drugs to rats, antiviral activity in the sera was examined by the MAGI assay. Recently developed inhibitors for HIV-1 entry, two CXCR4 antagonists, TF14016 and FC131, and four fusion inhibitors, T-20, T-20EK, SC29EK, and TRI-1144, were evaluated using HIV-1 IIIB and HIV-1 BaL as representative CXCR4- and CCR5-tropic HIV-1 strains, respectively. CXCR4 antagonists were shown to only possess anti-HIV-1 IIIB activity, whereas fusion inhibitors showed both anti-HIV-1 IIIB and anti-HIV-1 BaL activities in rat sera. These results indicate that test drugs were successfully processed into the rat sera and could be detected by the MAGI assay. In this system, TRI-1144 showed the most potent and sustained antiviral activity. Sera from animals not administered drugs showed substantial anti-HIV-1 activity, indicating that relatively high dose or activity of the test drugs might be needed. In conclusion, the novel rat system established here, “phenotypic drug evaluation”, may be applicable for the evaluation of various antiviral drugs in vivo.

Specific Inhibition of SRC Kinase Impairs Malignant Glioma Growth In Vitro and In Vivo

Directory of Open Access Journals (Sweden)

Hanna Stedt

2012-01-01

Full Text Available Malignant glioma is a severe cancer with a poor prognosis. Local occurrence and rare metastases of malignant glioma make it a suitable target for gene therapy. Several studies have demonstrated the importance of Src kinase in different cancers. However, these studies have focused mainly on Src-deficient mice or pharmacological inhibitors of Src. In this study we have used Src small hairpin RNAs (shRNAs in a lentiviral backbone to mimic a long-term stable treatment and determined the role of Src in tumor tissues. Efficacy of Src shRNAs was confirmed in vitro demonstrating up to 90% target gene inhibition. In a mouse malignant glioma model, Src shRNA tumors were almost 50-fold smaller in comparison to control tumors and had significantly reduced vascularity. In a syngenic rat intracranial glioma model, Src shRNA-transduced tumors were smaller and these rats had a survival benefit over the control rats. In vivo treatment was enhanced by chemotherapy and histone deacetylase inhibition. Our results emphasise the importance of Src in tumorigenesis and demonstrate that it can be efficiently inhibited in vitro and in vivo in two independent malignant glioma models. In conclusion, Src is a potential target for RNA interference-mediated treatment of malignant glioma.

Simultaneous, noninvasive, in vivo, continuous monitoring of hematocrit, vascular volume, hemoglobin oxygen saturation, pulse rate and breathing rate in humans and other animal models using a single light source

Science.gov (United States)

Dent, Paul; Tun, Sai Han; Fillioe, Seth; Deng, Bin; Satalin, Josh; Nieman, Gary; Wilcox, Kailyn; Searles, Quinn; Narsipur, Sri; Peterson, Charles M.; Goodisman, Jerry; Mostrom, James; Steinmann, Richard; Chaiken, J.

2018-02-01

We previously reported a new algorithm "PV[O]H" for continuous, noninvasive, in vivo monitoring of hematocrit changes in blood and have since shown its utility for monitoring in humans during 1) hemodialysis, 2) orthostatic perturbations and 3) during blood loss and fluid replacement in a rat model. We now show that the algorithm is sensitive to changes in hemoglobin oxygen saturation. We document the phenomenology of the effect and explain the effect using new results obtained from humans and rat models. The oxygen sensitivity derives from the differential absorption of autofluorescence originating in the static tissues by oxy and deoxy hemoglobin. Using this approach we show how to perform simultaneous, noninvasive, in vivo, continuous monitoring of hematocrit, vascular volume, hemoglobin oxygen saturation, pulse rate and breathing rate in mammals using a single light source. We suspect that monitoring of changes in this suite of vital signs can be provided with improved time response, sensitivity and precision compared to existing methodologies. Initial results also offer a more detailed glimpse into the systemic oxygen transport in the circulatory system of humans.

Hydroxychloroquine Protects against Cardiac Ischaemia/Reperfusion Injury In Vivo via Enhancement of ERK1/2 Phosphorylation.

Directory of Open Access Journals (Sweden)

Lauren Bourke

Full Text Available An increasing number of investigations including human studies demonstrate that pharmacological ischaemic preconditioning is a viable way to protect the heart from myocardial ischaemia/reperfusion (I/R injury. This study investigated the role of hydroxychloroquine (HCQ in the heart during I/R injury. In vitro and in vivo models of myocardial I/R injury were used to assess the effects of HCQ. It was found that HCQ was protective in neonatal rat cardiomyocytes through inhibition of apoptosis, measured by TUNEL and cleaved caspase-3. This protection in vitro was mediated through enhancement of ERK1/2 phosphorylation mediated by HCQ in a dose-dependent fashion. A decrease in infarct size was observed in an in vivo model of myocardial I/R injury in HCQ treated animals and furthermore this protection was blocked in the presence of the ERK1/2 inhibitor U0126. For the first time, we have shown that HCQ promotes a preconditioning like protection in an in vivo simulated rat myocardial I/R injury model. Moreover, it was shown that HCQ is protective via enhanced phosphorylation of the pro-survival kinase ERK1/2.

Automatic Training of Rat Cyborgs for Navigation.

Science.gov (United States)

Yu, Yipeng; Wu, Zhaohui; Xu, Kedi; Gong, Yongyue; Zheng, Nenggan; Zheng, Xiaoxiang; Pan, Gang

2016-01-01

A rat cyborg system refers to a biological rat implanted with microelectrodes in its brain, via which the outer electrical stimuli can be delivered into the brain in vivo to control its behaviors. Rat cyborgs have various applications in emergency, such as search and rescue in disasters. Prior to a rat cyborg becoming controllable, a lot of effort is required to train it to adapt to the electrical stimuli. In this paper, we build a vision-based automatic training system for rat cyborgs to replace the time-consuming manual training procedure. A hierarchical framework is proposed to facilitate the colearning between rats and machines. In the framework, the behavioral states of a rat cyborg are visually sensed by a camera, a parameterized state machine is employed to model the training action transitions triggered by rat's behavioral states, and an adaptive adjustment policy is developed to adaptively adjust the stimulation intensity. The experimental results of three rat cyborgs prove the effectiveness of our system. To the best of our knowledge, this study is the first to tackle automatic training of animal cyborgs.

Preventive effects of bee pollen Cistus ladaniferus extract on bone loss in ovariectomized rats in vivo

International Nuclear Information System (INIS)

Yamaguchi, Masayoshi; Uchiyama, Satoshi; Nakagawa, Taeko

2007-01-01

The effect of bee pollen Cistus ladaniferus extract on ovariectomy (OVX)-induced bone loss in vivo was investigated. The water-solubilized extracts were obtained from the bee pollen of Cistus ladaniferus. Cistus extract (5.0 or 10.0 mg/100 g body weight) was orally administered once daily for 30 days to OVX rats. The analysis using a peripheral quantitative computed tomography (pQCT) showed that OVX-induced a significant decrease in mineral content, mineral density, and polar strength strain index in the femoral-metaphyseal tissues. These decreases were significantly prevented after the administration of Cistus extract (10.0 mg/100 g). Moreover, OVX-induced a significant decrease in calcium content in the femoral-diaphyseal and -metaphyseal tissues. This decrease was significantly prevented after the administration of cistus extract (5.0 or 10.0 mg/100 g). This study demonstrates that cistus extract has a preventive effect on OVX-induced bone loss in vivo. (author)

Magnet Tracking: a new tool for in vivo studies of the rat gastrointestinal motility.

Science.gov (United States)

Guignet, R; Bergonzelli, G; Schlageter, V; Turini, M; Kucera, P

2006-06-01

Digestive motility was studied in the rat using a miniaturized version of the Magnet Tracking system which monitored the progression of a small magnetic pill through the entire digestive tract. The dynamics of movement was followed and three-dimensional (3-D) images of digestive tract were generated. After a retention period in the stomach and rapid passage through duodenum, the magnet progressed along the small intestine with gradually decreasing speed and longer stationary periods. It remained in the caecum for variable intervals. In the colon, periods of progress alternated with long quiescent periods. Gastric activity oscillated at 5-6 min(-1). In the small intestine, two frequency domains coexisted, showing independent modulations and proximo-distal gradients (40 to >32 and 28 to >20 min(-1)). Caecal oscillations were of 1.5 min(-1). The data allowed the magnet location and calculation of gastric and small intestinal transit times (58 +/- 36 and 83 +/- 14 min respectively), both significantly prolonged by oleate administration (243 +/- 130 and 170 +/- 45 min respectively). Magnet Tracking is a non-invasive tool to study the in vivo spatial and temporal organization of gastrointestinal motility in the rat.

Statistical parametric mapping for effects of verapamil on olfactory connections of rat brain in vivo using manganese-enhanced MR imaging

International Nuclear Information System (INIS)

Soma, Tsutomu; Kurakawa, Masami; Koto, Daichi

2011-01-01

We investigated the effect of verapamil on the transport of manganese in the olfactory connections of rat brains in vivo using statistical parametric mapping and manganese-enhanced magnetic resonance (MR) imaging. We divided 12 7-week-old male Sprague-Dawley rats into 2 groups of six and injected 10 μL of saline into the right nasal cavities of the first group and 10 μL of verapamil (2.5 mg/mL) into the other group. Twenty minutes after the initial injection, we injected 10 μL of MnCl 2 (1 mol/L) into the right nasal cavities of both groups. We obtained serial T 1 -weighted MR images before administering the verapamil or saline and at 0.5, one, 24, 48, and 72 hours and 7 days after administering the MnCl 2 , spatially normalized the MR images on the rat brain atlas, and analyzed the data using voxel-based statistical comparison. Statistical parametric maps demonstrated the transport of manganese. Manganese ions created significant enhancement (t-score=36.6) 24 hours after MnCl 2 administration in the group administered saline but not at the same time point in the group receiving verapamil. The extent of significantly enhanced regions peaked at 72 hours in both groups and both sides of the brain. The peak of extent in the right side brain in the group injected with saline was 70.2 mm 3 and in the group with verapamil, 92.4 mm 3 . The extents in the left side were 64.0 mm 3 for the group with saline and 53.2 mm 3 for the group with verapamil. We applied statistical parametric mapping using manganese-enhanced MR imaging to demonstrate in vivo the transport of manganese in the olfactory connections of rat brains with and without verapamil and found that verapamil did affect this transport. (author)

Ex Vivo Assay of Electrical Stimulation to Rat Sciatic Nerves: Cell Behaviors and Growth Factor Expression.

Science.gov (United States)

Du, Zhiyong; Bondarenko, Olexandr; Wang, Dingkun; Rouabhia, Mahmoud; Zhang, Ze

2016-06-01

Neurite outgrowth and axon regeneration are known to benefit from electrical stimulation. However, how neuritis and their surroundings react to electrical field is difficult to replicate by monolayer cell culture. In this work freshly harvested rat sciatic nerves were cultured and exposed to two types of electrical field, after which time the nerve tissues were immunohistologically stained and the expression of neurotrophic factors and cytokines were evaluated. ELISA assay was used to confirm the production of specific proteins. All cell populations survived the 48 h culture with little necrosis. Electrical stimulation was found to accelerate Wallerian degeneration and help Schwann cells to switch into migratory phenotype. Inductive electrical stimulation was shown to upregulate the secretion of multiple neurotrophic factors. Cellular distribution in nerve tissue was altered upon the application of an electrical field. This work thus presents an ex vivo model to study denervated axon in well controlled electrical field, bridging monolayer cell culture and animal experiment. It also demonstrated the critical role of electrical field distribution in regulating cellular activities. © 2015 Wiley Periodicals, Inc.

A combined solenoid-surface RF coil for high-resolution whole-brain rat imaging on a 3.0 Tesla clinical MR scanner.

Science.gov (United States)

Underhill, Hunter R; Yuan, Chun; Hayes, Cecil E

2010-09-01

Rat brain models effectively simulate a multitude of human neurological disorders. Improvements in coil design have facilitated the wider utilization of rat brain models by enabling the utilization of clinical MR scanners for image acquisition. In this study, a novel coil design, subsequently referred to as the rat brain coil, is described that exploits and combines the strengths of both solenoids and surface coils into a simple, multichannel, receive-only coil dedicated to whole-brain rat imaging on a 3.0 T clinical MR scanner. Compared with a multiturn solenoid mouse body coil, a 3-cm surface coil, a modified Helmholtz coil, and a phased-array surface coil, the rat brain coil improved signal-to-noise ratio by approximately 72, 61, 78, and 242%, respectively. Effects of the rat brain coil on amplitudes of static field and radiofrequency field uniformity were similar to each of the other coils. In vivo, whole-brain images of an adult male rat were acquired with a T(2)-weighted spin-echo sequence using an isotropic acquisition resolution of 0.25 x 0.25 x 0.25 mm(3) in 60.6 min. Multiplanar images of the in vivo rat brain with identification of anatomic structures are presented. Improvement in signal-to-noise ratio afforded by the rat brain coil may broaden experiments that utilize clinical MR scanners for in vivo image acquisition. 2010 Wiley-Liss, Inc.

Gene delivery to pancreatic exocrine cells in vivo and in vitro

Directory of Open Access Journals (Sweden)

Houbracken Isabelle

2012-10-01

Full Text Available Abstract Background Effective gene transfer to the pancreas or to pancreatic cells has remained elusive although it is essential for studies of genetic lineage tracing and modulation of gene expression. Different transduction methods and viral vectors were tested in vitro and in vivo, in rat and mouse pancreas. Results For in vitro transfection/transduction of rat exocrine cells lipofection reagents, adenoviral vectors, and Mokola- and VSV-G pseudotyped lentiviral vectors were used. For in vivo transduction of mouse and rat pancreas adenoviral vectors and VSV-G lentiviral vectors were injected into the parenchymal tissue. Both lipofection of rat exocrine cell cultures and transduction with Mokola pseudotyped lentiviral vectors were inefficient and resulted in less than 4% EGFP expressing cells. Adenoviral transduction was highly efficient but its usefulness for gene delivery to rat exocrine cells in vitro was hampered by a drastic increase in cell death. In vitro transduction of rat exocrine cells was most optimal with VSV-G pseudotyped lentiviral vectors, with stable transgene expression, no significant effect on cell survival and about 40% transduced cells. In vivo, pancreatic cells could not be transduced by intra-parenchymal administration of lentiviral vectors in mouse and rat pancreas. However, a high efficiency could be obtained by adenoviral vectors, resulting in transient transduction of mainly exocrine acinar cells. Injection in immune-deficient animals diminished leukocyte infiltration and prolonged transgene expression. Conclusions In summary, our study remarkably demonstrates that transduction of pancreatic exocrine cells requires lentiviral vectors in vitro but adenoviral vectors in vivo.

Cyclosporine A administered during reperfusion fails to restore cardioprotection in prediabetic Zucker obese rats in vivo.

Science.gov (United States)

Huhn, R; Heinen, A; Hollmann, M W; Schlack, W; Preckel, B; Weber, N C

2010-12-01

Hyperglycaemia blocks sevoflurane-induced postconditioning, and cardioprotection in hyperglycaemic myocardium can be restored by inhibition of the mitochondrial permeability transition pore (mPTP). We investigated whether sevoflurane-induced postconditioning is also blocked in the prediabetic heart and if so, whether cardioprotection could be restored by inhibiting mPTP. Zucker lean (ZL) and Zucker obese (ZO) rats were assigned to one of seven groups. Animals underwent 25 min of ischaemia and 120 min of reperfusion. Control (ZL-/ZO Con) animals were not further treated. postconditioning groups (ZL-/ZO Sevo-post) received sevoflurane for 5 min starting 1min prior to the onset of reperfusion. The mPTP inhibitor cyclosporine A (CsA) was administered intravenously in a concentration of 5 (ZO CsA and ZO CsA+Sevo-post) or 10 mg/kg (ZO CsA10+Sevo-post) 5 min before the onset of reperfusion. At the end of reperfusion, infarct sizes were measured by TTC staining. Blood samples were collected to measure plasma levels of insulin, cholesterol and triglycerides. Sevoflurane postconditioning reduced infarct size in ZL rats to 35±12% (pfailed to restore cardioprotection in the prediabetic but normoglycaemic heart of Zucker obese rats in vivo. Copyright © 2009 Elsevier B.V. All rights reserved.

Effects of acute chlorpyrifos exposure on in vivo acetylcholine accumulation in rat striatum

International Nuclear Information System (INIS)

Karanth, Subramanya; Liu, Jing; Mirajkar, Nikita; Pope, Carey

2006-01-01

This study examined the acute effects of chlorpyrifos (CPF) on cholinesterase inhibition and acetylcholine levels in the striatum of freely moving rats using in vivo microdialysis. Adult, male Sprague-Dawley rats were treated with vehicle (peanut oil, 2 ml/kg) or CPF (84, 156 or 279 mg/kg, sc) and functional signs of toxicity, body weight and motor activity recorded. Microdialysis was conducted at 1, 4 and 7 days after CPF exposure for measurement of acetylcholine levels in striatum. Rats were then sacrificed and the contralateral striatum and diaphragm were collected for biochemical measurements. Few overt signs of cholinergic toxicity were noted in any rats. Body weight gain was significantly affected in the high-dose (279 mg/kg) group only, while motor activity (nocturnal rearing) was significantly reduced in all CPF-treated groups at one day (84 mg/kg) or from 1-4 days (156 and 279 mg/kg) after dosing. Cholinesterase activities in both diaphragm and striatum were markedly inhibited (50-92%) in a time-dependent manner, but there were relatively minimal dose-related changes. In contrast, time- and dose-dependent changes in striatal acetylcholine levels were noted, with significantly higher levels noted in the high-dose group compared to other groups. Maximal increases in striatal acetylcholine levels were observed at 4-7 days after dosing (84 mg/kg, 7-9-fold; 156 mg/kg, 10-13-fold; 279 mg/kg, 35-57-fold). Substantially higher acetylcholine levels were noted when an exogenous cholinesterase inhibitor was included in the perfusion buffer, but CPF treatment-related differences were substantially lower in magnitude under those conditions. The results suggest that marked differences in acetylcholine accumulation can occur with dosages of CPF eliciting relatively similar degrees of cholinesterase inhibition. Furthermore, the minimal expression of classic signs of cholinergic toxicity in the presence of extensive brain acetylcholine accumulation suggests that some

In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

International Nuclear Information System (INIS)

Golberg, A; Laufer, S; Rabinowitch, H D; Rubinsky, B

2011-01-01

Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 deg. C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

Energy Technology Data Exchange (ETDEWEB)

Golberg, A; Laufer, S [Center for Bioengineering in the Service of Humanity and Society, School of Computer Science and Engineering, Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Rabinowitch, H D [Robert H Smith Faculty of Agriculture, Food and Environment, Robert H Smith Institute of Plant Science and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76 100 (Israel); Rubinsky, B, E-mail: Rabin@agri.huji.ac.il [Department of Mechanical Engineering, Graduate Program in Biophysics, University of California at Berkeley, Berkeley, CA 84720 (United States)

2011-02-21

Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 deg. C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

Three-dimensional Hessian matrix-based quantitative vascular imaging of rat iris with optical-resolution photoacoustic microscopy in vivo

Science.gov (United States)

Zhao, Huangxuan; Wang, Guangsong; Lin, Riqiang; Gong, Xiaojing; Song, Liang; Li, Tan; Wang, Wenjia; Zhang, Kunya; Qian, Xiuqing; Zhang, Haixia; Li, Lin; Liu, Zhicheng; Liu, Chengbo

2018-04-01

For the diagnosis and evaluation of ophthalmic diseases, imaging and quantitative characterization of vasculature in the iris are very important. The recently developed photoacoustic imaging, which is ultrasensitive in imaging endogenous hemoglobin molecules, provides a highly efficient label-free method for imaging blood vasculature in the iris. However, the development of advanced vascular quantification algorithms is still needed to enable accurate characterization of the underlying vasculature. We have developed a vascular information quantification algorithm by adopting a three-dimensional (3-D) Hessian matrix and applied for processing iris vasculature images obtained with a custom-built optical-resolution photoacoustic imaging system (OR-PAM). For the first time, we demonstrate in vivo 3-D vascular structures of a rat iris with a the label-free imaging method and also accurately extract quantitative vascular information, such as vessel diameter, vascular density, and vascular tortuosity. Our results indicate that the developed algorithm is capable of quantifying the vasculature in the 3-D photoacoustic images of the iris in-vivo, thus enhancing the diagnostic capability of the OR-PAM system for vascular-related ophthalmic diseases in vivo.

Endothelin B receptors contribute to retinal ganglion cell loss in a rat model of glaucoma.

Directory of Open Access Journals (Sweden)

Alena Z Minton

Full Text Available Glaucoma is an optic neuropathy, commonly associated with elevated intraocular pressure (IOP characterized by optic nerve degeneration, cupping of the optic disc, and loss of retinal ganglion cells which could lead to loss of vision. Endothelin-1 (ET-1 is a 21-amino acid vasoactive peptide that plays a key role in the pathogenesis of glaucoma; however, the receptors mediating these effects have not been defined. In the current study, endothelin B (ET(B receptor expression was assessed in vivo, in the Morrison's ocular hypertension model of glaucoma in rats. Elevation of IOP in Brown Norway rats produced increased expression of ET(B receptors in the retina, mainly in retinal ganglion cells (RGCs, nerve fiber layer (NFL, and also in the inner plexiform layer (IPL and inner nuclear layer (INL. To determine the role of ET(B receptors in neurodegeneration, Wistar-Kyoto wild type (WT and ET(B receptor-deficient (KO rats were subjected to retrograde labeling with Fluoro-Gold (FG, following which IOP was elevated in one eye while the contralateral eye served as control. IOP elevation for 4 weeks in WT rats caused an appreciable loss of RGCs, which was significantly attenuated in KO rats. In addition, degenerative changes in the optic nerve were greatly reduced in KO rats compared to those in WT rats. Taken together, elevated intraocular pressure mediated increase in ET(B receptor expression and its activation may contribute to a decrease in RGC survival as seen in glaucoma. These findings raise the possibility of using endothelin receptor antagonists as neuroprotective agents for the treatment of glaucoma.

In vivo pretreatment of Eudrilus eugeniae powder attenuates β-adrenoceptor toxicity mediated by isoproterenol in rat model

Directory of Open Access Journals (Sweden)

Jaganathan Anitha

2016-08-01

Full Text Available The present study was designed to discover the potential cardioprotective function of earthworm powder (EWP extracted from Eudrilus eugeniae on isoproterenol (ISO-induced myocardial infarction in male Wistar rats. The rats were divided into four groups, with six rats in each group. Certain rats were pretreated with EWP (200 mg/kg bwt (Group III, and a myocardial infarction was then induced by subcutaneous injection of ISO (85 mg/kg bwt (Group II. Oral pretreatment of 200 mg/kg bwt of EWP for 28 days significantly (p > 0.05 improved the blood profile levels, including (a the lipid profile of total cholesterol (TC, free fatty acids (FFA, and triglycerides (TG; (b low-density lipoprotein (LDL, very low-density lipoprotein (VLDL, high-density lipoprotein (HDL, and protein; and (c A/G ratio, glucose and uric acid levels. The electrophoretic pattern of elevated lactose dehydrogenase (LDH levels was recovered by EWP treatment as evidenced by comparison with ISO-induced rats with cardiac damage. The above results indicate that EWP (200 mg/kg bwt provides a cardioprotective effect by attenuating the blood profile, lipid profile, biochemical levels, and LDH patterns in rats that experienced an ISO-induced myocardial infarction.

Evaluation of adriamycin nephropathy by an in vivo electron paramagnetic resonance

International Nuclear Information System (INIS)

Oteki, Takaaki; Nagase, Sohji; Yokoyama, Hidekatsu; Ohya, Hiroaki; Akatsuka, Takao; Tada, Mika; Ueda, Atsushi; Hirayama, Aki; koyama, Akio

2005-01-01

A rat model for human minimal change nephropathy was obtained by the intravenous injection of adriamycin (ADR) at 5 mg/kg. By using an in vivo electron paramagnetic resonance (EPR) spectrometer operating at 700 MHz, the temporal changes in signal intensities of a nitroxide radical, 4-hydroxyl-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), in the kidneys of rats with ADR nephropathy were investigated. The decay rate of the EPR signal intensity obtained in the kidney is indicative of the renal reducing ability. It was found that the reducing ability in the kidney declined on the 7th day after ADR administration and recovered after the 14th day. Impairment of the reducing ability occurred before the appearance of continuous urinary protein. The in vitro EPR study showed that this impairment of in vivo renal reducing ability is related to impairment of the reducing ability in the mitochondria

GABAergic mechanism mediated via D receptors in the rat periaqueductal gray participates in the micturition reflex: an in vivo microdialysis study.

Science.gov (United States)

Kitta, Takeya; Matsumoto, Machiko; Tanaka, Hiroshi; Mitsui, Takahiko; Yoshioka, Mitsuhiro; Nonomura, Katsuya

2008-06-01

The periaqueductal gray (PAG) is critically involved in the micturition reflex, but little is known about the neuronal mechanisms involved. The present study elucidated dynamic changes in dopamine (DA), glutamate and gamma-aminobutyric acid (GABA) in the rat PAG during the micturition reflex, with a focus on dopaminergic modulation using in vivo microdialysis combined with cystometrography. Extracellular levels of DA and glutamate increased, whereas levels of GABA decreased, in parallel with the micturition reflex. Application of a D(1) receptor antagonist into the PAG produced increases in maximal voiding pressure (MVP) and decreases in intercontraction interval (ICI), suggesting that the micturition reflex was facilitated by D(1) receptor blockade. The D(1) receptor antagonist prevented micturition-induced decreases in GABA efflux but had no effect on DA or glutamate. Neither a D(2) receptor antagonist nor a D(1)/D(2) receptor agonist affected these neurochemical and physiological parameters. Micturition-induced inhibition of GABA was not observed in 6-hydroxydopamine (6-OHDA)-lesioned rats, an animal model of Parkinson's disease. 6-OHDA-lesioned rats exhibited bladder hyperactivity evaluated by increases in MVP and decreases in ICI, mimicking facilitation of the micturition reflex induced by D(1) receptor blockade. These findings suggest that the micturition reflex is under tonic dopaminergic regulation through D(1) receptors, in which a GABAergic mechanism is involved. Bladder hyperactivity observed in 6-OHDA-lesioned rats may be caused by dysfunction of GABAergic regulation underlying the micturition reflex. The present findings contribute to our understanding not only of the neurophysiology of the micturition reflex but also of the pathophysiology of lower urinary tract dysfunction in patients with Parkinson's disease.

Steroid-associated osteonecrosis animal model in rats

Directory of Open Access Journals (Sweden)

Li-Zhen Zheng

2018-04-01

Full Text Available Summary: Objective: Established preclinical disease models are essential for not only studying aetiology and/or pathophysiology of the relevant diseases but more importantly also for testing prevention and/or treatment concept(s. The present study proposed and established a detailed induction and assessment protocol for a unique and cost-effective preclinical steroid-associated osteonecrosis (SAON in rats with pulsed injections of lipopolysaccharide (LPS and methylprednisolone (MPS. Methods: Sixteen 24-week-old male Sprague–Dawley rats were used to induce SAON by one intravenous injection of LPS (0.2 mg/kg and three intraperitoneal injections of MPS (100 mg/kg with a time interval of 24 hour, and then, MPS (40 mg/kg was intraperitoneally injected three times a week from week 2 until sacrifice. Additional 12 rats were used as normal controls. Two and six weeks after induction, animals were scanned by metabolic dual energy X-ray absorptiometry for evaluation of tissue composition; serum was collected for bone turnover markers, Microfil perfusion was performed for angiography, the liver was collected for histopathology and bilateral femora and bilateral tibiae were collected for histological examination. Results: Three rats died after LPS injection, i.e., with 15.8% (3/19 mortality. Histological evaluation showed 100% incidence of SAON at week 2. Dual energy X-ray absorptiometry showed significantly higher fat percent and lower lean mass in SAON group at week 6. Micro-computed tomography (Micro-CT showed significant bone degradation at proximal tibia 6 weeks after SAON induction. Angiography illustrated significantly less blood vessels in the proximal tibia and significantly more leakage particles in the distal tibia 2 weeks after SAON induction. Serum amino-terminal propeptide of type I collagen and osteocalcin were significantly lower at both 2 and 6 weeks after SAON induction, and serum carboxy-terminal telopeptide was significantly

Development of an in vivo animal model for skin penetration in hairless rats assessed by mass balance

DEFF Research Database (Denmark)

Simonsen, Lene; Petersen, Mads B; Benfeldt, Eva

2002-01-01

acid and (14)C-butyl salicylate were topically applied. Rapid and differentiated percutaneous absorption of both compounds were shown by urinary excretion data. For (14)C-salicylic acid the amount on the skin surface, in the stratum corneum and in the viable skin was determined. Total mass balance...... rat and free mobility throughout the test period. By consecutive tape stripping, monitored by measurements of transepidermal water loss and confirmed by histological examination of skin biopsies, 10 tape strippings were found to remove the stratum corneum completely. For assessment of the model, (14)C-salicylic...

Differences between in vitro and in vivo degradation of LHRH by rat brain and other organs

International Nuclear Information System (INIS)

Carone, F.A.; Stetler-Stevenson, M.A.; May, V.; LaBarbera, A.; Flouret, G.

1987-01-01

Homogenates of brain, pituitary, liver, lung, ovary, and testes were incubated with [ 1 -3,4- 3 H] luteinizing hormone-releasing hormone ([ 3 H]LHRH), and the profiles of metabolites generated as a function of time were determined. After 5 min of incubation, 5 was the predominant metabolite in most homogenates. Although the profiles of metabolites varied at different times intervals, metabolites 2, 3, 4, and 5, and in some instances 7 and 9, appeared to form simultaneously and were detectable at 10 min. Neither metabolite 6 nor other larger metabolites formed initially as dominant degradation products. The findings suggest cleavage of LHRH by the simultaneous action of several endopeptidases. After a single vascular transit of [ 3 H]LHRH, metabolites were determined in the venous blood of liver, lung, and brain of rats in vivo. There were no metabolites of [ 3 H]LHRH in venous blood liver and lung; however, metabolites 2-4 present in venous blood of the brain. Incubation of rat anterior pituitary cells with [ 3 H]LHRH yielded metabolites 1-4 but not metabolites 5 or 9 as in homogenates. Incubation of [ 3 H]LHRH with porcine follicular granulosa cells resulted in the generation of metabolites 2-7 and 9, similar to the profile in homogenates. Thus, since homogenates contain enzymes of disrupted cells, they do not always reflect mechanisms for in vivo hydrolysis of circulating LHRH. Brain degraded 12.1% of LHRH during a single vascular transit and may account for substantial degradation of the circulating hormone

Differences between in vitro and in vivo degradation of LHRH by rat brain and other organs

Energy Technology Data Exchange (ETDEWEB)

Carone, F.A.; Stetler-Stevenson, M.A.; May, V.; LaBarbera, A.; Flouret, G.

1987-09-01

Homogenates of brain, pituitary, liver, lung, ovary, and testes were incubated with (rats in vivo. There were no metabolites of (/sup 3/H)LHRH in venous blood liver and lung; however, metabolites 2-4 present in venous blood of the brain. Incubation of rat anterior pituitary cells with (/sup 3/H)LHRH yielded metabolites 1-4 but not metabolites 5 or 9 as in homogenates. Incubation of (/sup 3/H)LHRH with porcine follicular granulosa cells resulted in the generation of metabolites 2-7 and 9, similar to the profile in homogenates. Thus, since homogenates contain enzymes of disrupted cells, they do not always reflect mechanisms for in vivo hydrolysis of circulating LHRH. Brain degraded 12.1% of LHRH during a single vascular transit and may account for substantial degradation of the circulating hormone.

miR-494 up-regulates the PI3K/Akt pathway via targetting PTEN and attenuates hepatic ischemia/reperfusion injury in a rat model.

Science.gov (United States)

Su, Song; Luo, De; Liu, Xiangdong; Liu, Jiang; Peng, Fangyi; Fang, Cheng; Li, Bo

2017-10-31

A rat HIRI model was constructed and treated with an intraperitoneal injection of agomir- miR-494 or agomir-NC (negative control) for 7 days after the surgery. The pathophysiological changes in sham-operated rats, HIRI, HIRI + agomir- miR-494 , and HIRI + agomir-NC were compared. The effect of miR-494 was also assessed in an H 2 O 2 -induced apoptosis model. Hepatic AML12 cells were transfected with mimics NC or miR-494 mimics, followed by 6-h H 2 O 2 treatment. Cell proliferation and apoptosis were detected by CCK8 assay and flow cytometry, respectively. Further, the miR-494 target gene was identified by luciferase reporter assay, and verified both in vitro and in vivo experiments. The activity of AKT pathway was further analyzed in vivo by Western blot. HIRI + agomir- miR-494 rats exhibited significantly higher miR-494 expression, lower serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and glutamate dehydrogenase (GLDH) level, lower hepatic MDA, TOA, and OSI, alleviated hepatic necrosis, reduced hepatocyte apoptosis, and decreased expression of apoptosis-related proteins, when compared with HIRI + agomir-NC rats ( P <0.05 or 0.01). After H 2 O 2 treatment, AML-12 cells transfected with miR-494 mimics had significantly higher proliferation and lower apoptosis rate compared with mimics NC group ( P <0.01). PTEN was identified as an miR-494 target gene. PTEN expression was significantly down-regulated in AML12 cells transfected with miR-494 mimics, and was up-regulated by treatment of miR-494 inhibitor ( P <0.01). Moreover, HIRI + agomir- miR-494 rats exhibited significantly lower PTEN expression, and higher p-AKT, p-mTOR, and p-p70S6K levels compared with HIRI + agomir-NC rats. Therefore, miR-494 protected rats against hepatic ischemia/reperfusion (I/R) injury through down-regulating its downstream target gene PTEN , leading to the activation of PI3K/AKT signaling pathway. © 2017 The Author(s).

Insulin action in vivo: studies in control and exercise trained rats

Energy Technology Data Exchange (ETDEWEB)

James, D.E.

1984-01-01

This thesis is primarily concerned with in vivo insulin action and how this is modified by exercise training. The aims are; to define differential insulin action within the major insulin sensitive tissues; to characterize the relationship between these individual responses and whole body insulin action; and to examine the effect of exercise training on whole body and differential tissue insulin action. A technique, based on the euglycaemic clamp, is described for examining in vivo insulin action on glucose utilization and storage in individual tissues in the conscious, unrestrained rat. Tissue glucose metabolic rate (Rg') was estimated using (/sup 3/H)-2-deoxyglucose and glucose disposal was examined by measuring glycogen content and /sup 14/C-glucose incorporation into tissue glycogen or lipids. Elevating plasma insulin to 150 mU/l resulted in significant increases of glucose utilization in skeletal muscle and adipose tissue. Oxidative skeletal muscle could account for up to 70% of total glucose disposal whereas adipose tissue and liver could account for less than 3%. The following conclusions have been drawn from these studies. The whole body insulin response curve for glucose utilization closely reflects muscle glucose metabolism; mild elevations in plasma insulin will markedly elevate the glucose utilization rate in oxidative but not glycolytic skeletal muscle fibers; the increased whole body insulin sensitivity which is observed following exercise training is due to increased insulin sensitivity in skeletal muscle. These results indicate that exercise training will undoubtedly result in improved glucose disposal in the prandial state. This emphasises the potential benefit of exercise in obesity and Type II diabetes.

Testosterone-induced benign prostatic hyperplasia rat and dog as facile models to assess drugs targeting lower urinary tract symptoms.

Directory of Open Access Journals (Sweden)

Jing Li

Full Text Available Benign prostatic hyperplasia (BPH is an age-related disease, affecting a majority of elderly men worldwide. Medical management of BPH is an alternative to surgical treatment of this disease. Currently, α1-adrenergic receptor (α1-AR antagonists are among the first line drugs to treat BPH by reducing the tension of urinary track and thus the obstructive symptoms in voiding. In drug development, old male dogs with spontaneous BPH are considered the golden standard of the animal models. However, old dogs (>6 years are expensive and not all old dogs develop BPH. So it is necessary to develop more accessible animal models for drug efficacy evaluation. Here we describe the development of testosterone-induced BPH models in both rats and young adult dogs and their applications in the in vivo evaluation of α1-AR antagonist. The BPH rats and dogs induced by chronic testosterone treatment have significantly increased micturition frequency and reduced mean voided volume, very similar to the clinical symptoms of BPH patients. Silodosin, an α1-AR antagonist, significantly reduces the urinary frequency and increases the voided volume in BPH model animals in a dose-dependent manner. The results demonstrate that testosterone-induced BPH rat and dog models might provide a more efficient way to evaluate micturition behavior in anti-BPH drug studies.

Osteogenic actions of metoprolol in an ovariectomized rat model of menopause.

Science.gov (United States)

Zang, Yuan; Tan, Quanchang; Ma, Xiangyu; Zhao, Xiong; Lei, Wei

2016-09-01

Osteoporosis and hypertension are age-related chronic diseases with increased morbidity rates among postmenopausal women. Clinical epidemiological investigations have demonstrated that hypertensive patients treated with β1-selective β-blockers have a higher bone mineral density (BMD) and lower fracture risk. Nevertheless, no fundamental studies have examined the relationships between β1-selective β-blockers and these effects. The present study explored the effects and mechanisms of metoprolol in the in vitro treatment of osteoblasts and the in vivo treatment of ovariectomy-induced osteoporosis in rats. Primary osteoblasts were obtained by digestion of the cranial bones of 24-hour-old Sprague-Dawley rats. After metoprolol treatment, cell proliferation and differentiation capacities were assessed at the corresponding time points. In addition, 3-month-old female Sprague-Dawley rats (200-220 g) were divided into a sham-operated group (n = 8) and three ovariectomized (OVX) (bilateral removal of ovaries) groups as follows: vehicle (OVX; n = 8), low-dose metoprolol (L-M, oral, 120 mg/kg/d; n = 8), and high-dose metoprolol (H-M, oral, 240 mg/kg/d; n = 8). After 12 weeks of metoprolol treatment, BMD, microarchitecture, and biomechanical properties were evaluated. The results indicated that the treatments with 0.01 to 0.1 μM metoprolol increased osteoblast proliferation, alkaline phosphatase activity, and calcium mineralization, and promoted the expression of osteogenic genes. The in vivo study indicated that administration of metoprolol to OVX rats resulted in maintenance of the BMDs of the L4 vertebrae. Moreover, amelioration of trabecular microarchitecture deterioration and preservation of bone biomechanical properties were detected in the trabecular bones of the OVX rats. Our findings indicate that metoprolol prevents estrogen deficiency-induced bone loss by increasing the number and enhancing the biological functions of osteoblasts, implying

Evaluation of drug penetration into the brain: a double study by in vivo imaging with positron emission tomography and using an in vitro model of the human blood-brain barrier

International Nuclear Information System (INIS)

Josserand, V.; Jego, B.; Duconge, F.; Tavitian, B.; Pelerin, H.; Ezan, E.; Mabondzo, A.; Bruin, B. de; Kuhnast, B.; Dolle, F.

2004-01-01

The blood brain barrier (BBB) passage of a set of radiopharmaceuticals candidates was measured both in vitro using a newly developed co-culture based model of human BBB and in vivo by positron emission tomography (PET). MATERIAL and METHODS: As an in vitro BBB model, a co-culture of primary human brain endothelial cells and primary human astrocytes was used. Dynamic PET studies were performed simultaneously on 4 anesthetized rats with the EXACT HR+ camera. Volumes of interest (VOI) were manually defined on the tomographic images in order to determine the pharmacokinetics of the compounds in various organs, including brain. The in vivo input function was measured by radioactivity counting of arterial blood samples. A two-compartment model analysis was used to compute the exchanging rate constants between blood and brain and to calculate the in vivo permeability coefficient. RESULTS: There was an excellent correlation between the in vitro and in vivo permeability coefficients (r = 0.99; p < 0.001) as well as between the in vivo distribution volume and the in vitro efflux /influx permeability coefficients ratio (r = 0.76). CONCLUSION: This double study evidenced a close relationship between the in vitro and the in vivo approaches for the assessment of the BBB passage. Hence, small animal PET imaging appeared suitable to screen drugs or radiopharmaceuticals candidates aimed at cerebral targets directly in the real-life situation in vivo. (author)

Interaction of hematoporphyrin derivative, light, and ionizing radiation in a rat glioma model

International Nuclear Information System (INIS)

Kostron, H.; Swartz, M.R.; Miller, D.C.; Martuza, R.L.

1986-01-01

The effects of hematoporphyrin derivative, light, and cobalt 60 ( 60 Co) irradiation were studied in a rat glioma model using an in vivo and an in vitro clonogenic assay. There was no effect on tumor growth by visible light or by a single dose of 60 Co irradiation at 4 Gy or 8 Gy, whereas 16 Gy inhibited tumor growth to 40% versus the control. Hematoporphyrin derivative alone slightly stimulated growth (P less than 0.1). Light in the presence of 10 mg hematoporphyrin derivative/kg inhibited tumor growth to 32%. 60 Co irradiation in the presence of hematoporphyrin derivative produced a significant tumor growth inhibition (P less than 0.02). This growth inhibition was directly related to the concentration of hematoporphyrin derivative. The addition of 60 Co to light in the presence of hematoporphyrin derivative produced a greater growth inhibition than light or 60 Co irradiation alone. This effect was most pronounced when light was applied 30 minutes before 60 Co irradiation. Our experiments in a subcutaneous rat glioma model suggest a radiosensitizing effect of hematoporphyrin derivative. Furthermore, the photodynamic inactivation is enhanced by the addition of 60 Co irradiation. These findings may be of importance in planning new treatment modalities in malignant brain tumors

Histochemical detection of the in vivo produced cellular aldehydes by means of direct Schiff's reaction in CCl/sub 4/ intoxicated rat liver

Energy Technology Data Exchange (ETDEWEB)

Taper, H.S.; Somer, M.P.; Lans, M.; Gerlache, J. de; Roberfroid, M.

1988-04-01

A histochemical technique for detection of the in vivo induced cellular aldehydes based on the direct Schiff's reaction is reported in this paper. CCl/sub 4/-intoxicated rat liver was used as an experimental model. Fresh and non-pretreated rat liver cryostat sections fixed in 10% formol calcium solution and washed in distilled water were exposed to Schiff's reagent. The sections were then immersed in two baths of sodium bisulphite solution, then in water, dehydrated in ethanol, cleared in xylene and mounted in a synthetic anhydrous mounting medium. As Schiff positive areas presented well circumscribed foci which increased with time following intoxication, semiquantitative planimetric measurements were feasible. The direct Schiff's reaction detects cellular aldehydes in a sensitive, rapid histologically and topographically estimable way. The appearance of these aldehydes precedes distinctly morphological alterations detectable by other histochemical of histological techniques. No positive results were obtained in control, non-intocicated rat livers. Inhibitons of this direct Schiff's was obtained in positive control rat liver sections preincubated in solutions of aldehyde blockers. Histochemical detection of aldehydes may give useful information on different aspects of tissue and organ intoxication such as their topography, appearance, evolution, extension, consequences and effects of treatment. The direct Schiff's reaction can be considered as a valuable tool in fundamental and applied reasearch dealing with various toxicological, environmental, pathological, cancer-related and therapeutic problems.

Transdifferentiated rat pancreatic progenitor cells (AR42J-B13/H) respond to phenobarbital in a rat hepatocyte-specific manner.

Science.gov (United States)

Osborne, M; Haltalli, M; Currie, R; Wright, J; Gooderham, N J

2016-07-01

Phenobarbital (PB) is known to produce species-specific effects in the rat and mouse, being carcinogenic in certain mouse strains, but only in rats if treated after a DNA damaging event. PB treatment in the rat and mouse also produces disparate effects on cell signalling and miRNA expression profiles. These responses are induced by short term and prolonged PB exposure, respectively, with the latter treatments being difficult to examine mechanistically in primary hepatocytes due to rapid loss of the original hepatic phenotype and limited sustainability in culture. Here we explore the rat hepatocyte-like B13/H cell line as a model for hepatic response to PB exposure in both short-term and longer duration treatments. We demonstrate that PB with Egf treatment in the B13/H cells resulted in a significant increase in Erk activation, as determined by the ratio of phospho-Erk to total Erk, compared to Egf alone. We also show that an extended treatment with PB in the B13/H cells produces a miRNA response similar to that seen in the rat in vivo, via the time-dependent induction of miR-182/96. Additionally, we confirm that B13/H cells respond to Car activators in a typical rat-specific manner. These data suggest that the B13/H cells produce temporal responses to PB that are comparable to those reported in short-term primary rat hepatocyte cultures and in the longer term are similar to those in the rat in vivo. Finally, we also show that Car-associated miR-122 expression is decreased by PB treatment in B13/H cells, a PB-induced response that is common to the rat, mouse and human. We conclude that the B13/H cell system produces a qualitative response comparable to the rat, which is different to the response in the mouse, and that this model could be a useful tool for exploring the functional consequences of PB-sensitive miRNA changes and resistance to PB-mediated tumours in the rat. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ex vivo effects of lysine clonixinate on cyclooxygenases in rat lung and stomach preparations.

Science.gov (United States)

Franchi, A M; Di Girolamo, G; De los Santos, A R; Marti, M L; Gimeno, M A

1999-01-01

Lysine clonixinate (LC) is an anti-inflammatory, anti-pyretic and analgesic drug with minor digestive side effects, which might suggest a weak COX-1 inhibitor. The aim of this study focused on ex vivo effects of LC 40 mg/kg ip and indomethacin (INDO) 10 mg/kg ip in lung and stomach preparations of control rats and LPS-treated rats (5 mg/kg ip). The non-steroidal antiinflammatory drugs were administered concomitantly, following three hours and before one, two or three hours of LPS treatment. Tissues were weighed and incubated in 2 ml of Kress Ringer Bicarbonate buffer containing glucose (11 mM) under an atmosphere of 95% oxygen and 5% CO(2). Approximately 200 mg of tissue were used for each determination; 0.25 microCi of (14)C-arachidonic acid was added to each tube and the tissues were incubated for 60 min. Prostanoids were extracted from the incubation medium and separated by TLC. Results were expressed as a percentage of the total radioactivity of the plates (% of cpm on plate/100 mg ww). It was found that LC animals that were not given LPS did not modify the synthesis of PGE(2); in lung and stomach tissues showing that did not inhibit COX-1 activity. However, LC inhibited clearly the synthesis of PGE(2) in both preparations obtained from LPS-treated animals. The inhibition was shown when the rats were treated concomitantly, 3 h after or 1 or 2 h before the injection of LPS.

Enzymatic removal of O6-ethylguanine from mitochondrial DNA in rat tissues exposed to N-ethyl-N-nitrosourea in vivo

International Nuclear Information System (INIS)

Satoh, M.S.; Huh, N.; Rajewsky, M.F.; Kuroki, T.

1988-01-01

DNA repair is essential for maintaining the integrity of the genetic material, and a number of DNA repair mechanisms have been fairly well characterized for the nuclear DNA of eukaryotic cells as well as prokaryotes. However, little is know about DNA repair in mitochondria. Using highly sensitive immunoanalytical methods to detect specific DNA alkylation products, the authors found active removal of O 6 -ethyl-2'-deoxyguanosine (O 6 -EtdGuo) from rat liver mitochondrial DNA after pulse-exposure to N-ethyl-N-nitrosourea in vivo. In the kidney, O 6 -EtdGuo was removed from mitochondrial DNA with moderate efficiency, but nearly no removal was observed from the DNA of brain mitochondria. Among the rat tissues examined, the kinetics of O 6 -EtdGuo elimination from mitochondrial DNA was very similar to the kinetics of removal from nuclear DNA. O 4 -Ethyl-2'-deoxythymidine, another premutagenic DNA ethylation product, was stable in both mitochondrial and nuclear DNA of rat liver

Identification of adulterants in a Chinese herbal medicine by LC-HRMS and LC-MS-SPE/NMR and comparative in vivo study with standards in a hypertensive rat model.

Science.gov (United States)

Kesting, Julie Regitze; Huang, Jingqi; Sørensen, Dan

2010-02-05

Based on anecdotal evidence of anti-hypertensive effect of Gold Nine Soft Capsules, an in vivo study of this complex Chinese "herbal-based" medicine was initiated. Dosage of the content of Gold Nine capsules in spontaneous hypertensive rats showed a remarkably good effect. This led to further investigation of the components of the preparation and eventual identification of three known anti-hypertensive drugs; amlodipine, indapamide and valsartan, which were not declared on the label. Compounds were rapidly identified using LC-HRMS and LC-MS-SPE/NMR, quantified by HPLC, and the in vivo activity of a combination of commercially purchased standards was shown to be equivalent to that of the capsule content. Adulteration of herbal remedies and dietary supplements with synthetic drugs is an increasing problem that may lead to serious adverse effects. LC-MS-SPE/NMR as a method for the rapid identification of such adulterants is highlighted in this case study.

Image-based in vivo assessment of targeting accuracy of stereotactic brain surgery in experimental rodent models

Science.gov (United States)

Rangarajan, Janaki Raman; Vande Velde, Greetje; van Gent, Friso; de Vloo, Philippe; Dresselaers, Tom; Depypere, Maarten; van Kuyck, Kris; Nuttin, Bart; Himmelreich, Uwe; Maes, Frederik

2016-11-01

Stereotactic neurosurgery is used in pre-clinical research of neurological and psychiatric disorders in experimental rat and mouse models to engraft a needle or electrode at a pre-defined location in the brain. However, inaccurate targeting may confound the results of such experiments. In contrast to the clinical practice, inaccurate targeting in rodents remains usually unnoticed until assessed by ex vivo end-point histology. We here propose a workflow for in vivo assessment of stereotactic targeting accuracy in small animal studies based on multi-modal post-operative imaging. The surgical trajectory in each individual animal is reconstructed in 3D from the physical implant imaged in post-operative CT and/or its trace as visible in post-operative MRI. By co-registering post-operative images of individual animals to a common stereotaxic template, targeting accuracy is quantified. Two commonly used neuromodulation regions were used as targets. Target localization errors showed not only variability, but also inaccuracy in targeting. Only about 30% of electrodes were within the subnucleus structure that was targeted and a-specific adverse effects were also noted. Shifting from invasive/subjective 2D histology towards objective in vivo 3D imaging-based assessment of targeting accuracy may benefit a more effective use of the experimental data by excluding off-target cases early in the study.

In vivo dosimetry of high-dose fractionated irradiation in an experimental set-up with rats

Energy Technology Data Exchange (ETDEWEB)

Fortan, L; Van Hecke, H; Van Duyse, B; De Neve, W; De Meerleer, B [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde; Pattyn, P; Van Renthergem, K [Ghent University (Belgium). Dept. of Surgery

1995-12-01

The feasibility to irradiate a limited section of a rat abdomen with well-defined edges was assessed. Because of the relative small volume involved, in vivo dosimetry with TLDs was necessary in providing us information about the accuracy of the irradiation method. Three to five days prior to the start of the radiotherapy treatment, two plastic strips - each containing a TLD-dosimeter (Harshaw TLD10 LiF rods, 1 mm dia x 6 mm) sealed in polyethylene tubing, and a lead bean - were implanted in the rat abdomen. The plastic strips made a closed loop around the bowel, through the mesenterium, and were fixed with a single stitch on the inner abdominal wall. One loop was made in the hepatic area; another was made in the lower abdomen, around the rectosigmoid. Conscious animals were irradiated using a purpose-build plexi-holder, with rear legs immobilised to avoid longitudinal movements. The implanted lead beans enabled us to simulate the rat prior to each radiation session. This way, the radiation field could be set up individually for each rat, in such way that the rectosigmoid area received full dose and the hepatic area received no irradiation dose at all. Irradiation was carried out, using 5 MV photons of a linear accelerator. Fifteen animals per group were irradiated according a conventional (2.0 Gy / fraction; 5 fractions / week) or a hyperfractionated (1.6 Gy / fraction; 2 daily fractions; 5 days / week) schedule, with different total doses. Prior to implantation, TLDs were individually calibrated and checked for stability. After removal from the abdomen . TLDs were tested again for accuracy. TLDs with an unacceptable read-out curve were rejected (about 2 to 4 TLDs per group of 15). The obtained accumulated doses - as determined by TLD read-outs-were comparable to the theoretical doses, indicating that fractionated radiation of small fields, with well defined mark off, in rats is feasible.

In vivo dosimetry of high-dose fractionated irradiation in an experimental set-up with rats

International Nuclear Information System (INIS)

Fortan, L.; Van Hecke, H.; Van Duyse, B.; De Neve, W.; De Meerleer, B.; Pattyn, P.; Van Renthergem, K.

1995-01-01

The feasibility to irradiate a limited section of a rat abdomen with well-defined edges was assessed. Because of the relative small volume involved, in vivo dosimetry with TLDs was necessary in providing us information about the accuracy of the irradiation method. Three to five days prior to the start of the radiotherapy treatment, two plastic strips - each containing a TLD-dosimeter (Harshaw TLD10 LiF rods, 1 mm dia x 6 mm) sealed in polyethylene tubing, and a lead bean - were implanted in the rat abdomen. The plastic strips made a closed loop around the bowel, through the mesenterium, and were fixed with a single stitch on the inner abdominal wall. One loop was made in the hepatic area; another was made in the lower abdomen, around the rectosigmoid. Conscious animals were irradiated using a purpose-build plexi-holder, with rear legs immobilised to avoid longitudinal movements. The implanted lead beans enabled us to simulate the rat prior to each radiation session. This way, the radiation field could be set up individually for each rat, in such way that the rectosigmoid area received full dose and the hepatic area received no irradiation dose at all. Irradiation was carried out, using 5 MV photons of a linear accelerator. Fifteen animals per group were irradiated according a conventional (2.0 Gy / fraction; 5 fractions / week) or a hyperfractionated (1.6 Gy / fraction; 2 daily fractions; 5 days / week) schedule, with different total doses. Prior to implantation, TLDs were individually calibrated and checked for stability. After removal from the abdomen . TLDs were tested again for accuracy. TLDs with an unacceptable read-out curve were rejected (about 2 to 4 TLDs per group of 15). The obtained accumulated doses - as determined by TLD read-outs-were comparable to the theoretical doses, indicating that fractionated radiation of small fields, with well defined mark off, in rats is feasible

Helicobacter pylori-induced gastric pathology: insights from in vivo and ex vivo models

Directory of Open Access Journals (Sweden)

Michael D. Burkitt

2017-02-01

Full Text Available Gastric colonization with Helicobacter pylori induces diverse human pathological conditions, including superficial gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT lymphoma, and gastric adenocarcinoma and its precursors. The treatment of these conditions often relies on the eradication of H. pylori, an intervention that is increasingly difficult to achieve and that does not prevent disease progression in some contexts. There is, therefore, a pressing need to develop new experimental models of H. pylori-associated gastric pathology to support novel drug development in this field. Here, we review the current status of in vivo and ex vivo models of gastric H. pylori colonization, and of Helicobacter-induced gastric pathology, focusing on models of gastric pathology induced by H. pylori, Helicobacter felis and Helicobacter suis in rodents and large animals. We also discuss the more recent development of gastric organoid cultures from murine and human gastric tissue, as well as from human pluripotent stem cells, and the outcomes of H. pylori infection in these systems.

Microscopy of bacterial translocation during small bowel obstruction and ischemia in vivo – a new animal model

Directory of Open Access Journals (Sweden)

Hafner Mathias

2002-08-01

Full Text Available Abstract Background Existing animal models provide only indirect information about the pathogenesis of infections caused by indigenous gastrointestinal microflora and the kinetics of bacterial translocation. The aim of this study was to develop a novel animal model to assess bacterial translocation and intestinal barrier function in vivo. Methods In anaesthetized male Wistar rats, 0.5 ml of a suspension of green fluorescent protein-transfected E. coli was administered by intraluminal injection in a model of small bowel obstruction. Animals were randomly subjected to non-ischemic or ischemic bowel obstruction. Ischemia was induced by selective clamping of the terminal mesenteric vessels feeding the obstructed bowel loop. Time intervals necessary for translocation of E. coli into the submucosal stroma and the muscularis propria was assessed using intravital microscopy. Results Bacterial translocation into the submucosa and muscularis propria took a mean of 36 ± 8 min and 80 ± 10 min, respectively, in small bowel obstruction. Intestinal ischemia significantly accelerated bacterial translocation into the submucosa (11 ± 5 min, p E. coli were visible in frozen sections of small bowel, mesentery, liver and spleen taken two hours after E. coli administration. Conclusions Intravital microscopy of fluorescent bacteria is a novel approach to study bacterial translocation in vivo. We have applied this technique to define minimal bacterial transit time as a functional parameter of intestinal barrier function.

[Epididymis in an experimental model of DHT deficiency: immunolocalization of ERalpha and ERbeta in rat epididymal epithelial cells. In vivo and in vitro studies].

Science.gov (United States)

Kolasa, Agnieszka

2006-01-01

The aim of this study was to determine the effect of reduced availability of dihydrotestosterone (DHT) on the expression of estrogen receptors alpha and beta (ERalpha and ERbeta) in the epididymis in vivo and in vitro. Expression of estrogen receptors (ERs) is interesting because of the fact that the male reproductive system is controlled not only by androgens but also, in a far-reaching and complex manner, by estrogens. Control by estrogens is exercised through activation of ERs widely distributed in the epididymal epithelium. Epididymal epithelial cells contain a 5alpha-reductase (5alpha-red) which catalyzes the irreversible conversion of testosterone (T) into the most potent and chief androgen of the epididymis, dihydrotestosterone, known to maintain and regulate the structure and functions of the epididymis. Two isoforms of the 5alpha-red were identified: type 1 (5alpha-redl) and type 2 (5alpha-red2). 5alpha-reductase type 2 is more widely expressed in the epididymis than 5alpha-redl. DHT deficit was produced by inhibition of 5alpha-red2 using finasteride (Proscar, MSD Sweden), a steroid inhibitor of this enzyme. The study was performed in the adult, male Wistar rats randomly divided into control (K) and study (Fin56) groups (5 animals in each). Animals in the study group received 5mg finasteride/kg b.w., orally during 56 days (duration of one spermatogenesis). Immunoexpression of ERs was also studied in epididymal epithelial cells cultured with or without finasteride. It was shown that DHT deficiency, both in vivo and in vitro condition, modulated ERs expression in comparison to the epididymis from control rats and to epididymal cells cultured without finasteride. Distribution of ERalpha and ERbeta in epididymal cells changed (from nucleus to cytoplasm) and the level of ERs expression was markedly decreased. The present findings show that the DHT deficiency caused by finasteride altered the expression of ERalpha and ERbeta in the epididymis and possibly may

In vivo binding in rat brain and radiopharmaceutical preparation of radioiodinated HEAT, an alpha-1 adrenoceptor ligand

International Nuclear Information System (INIS)

Couch, M.W.; Greer, D.M.; Thonoor, C.M.; Williams, C.M.

1988-01-01

In vivo binding of [ 125 I]-2-[beta-(3-iodo-4-hydroxyphenyl)ethylaminomethyl tetralone) ([ 125 I]HEAT) to alpha-1 adrenoceptors in the rat brain was determined over 4 hr. Uptake in the thalamus and frontal cortex was approximately 0.1% injected dose per gram tissue. Thalamus/cerebellum ratios of 10:1 and frontal cortex/cerebellum ratios of 5:1 were found at 4 hr. Pretreatment with prazosin, an alpha-1 antagonist, completely inhibited the accumulation of [ 125 I]HEAT in thalamus and frontal cortex; yet uptake of radioactivity was not significantly affected by antagonists and agonists for other receptors classes (propranolol, beta-1; apomorphine, D-1; spiperone, D-2). Binding of [ 125 I]HEAT is saturable. At 4 hr, [ 125 I]HEAT or [ 123 I]HEAT was shown to be the only radioactive material in rat thalamus and frontal cortex. Iodine-123 HEAT and [ 125 I]HEAT were synthesized as radiopharmaceuticals within 3 hr in 99% radiochemical purity

Dopamine transporter imaging in the aged rat: a [123I]FP-CIT SPECT study

International Nuclear Information System (INIS)

Niñerola-Baizán, Aida; Rojas, Santiago; Roé-Vellvé, Núria; Lomeña, Francisco; Ros, Domènec

2015-01-01

Introduction: Rodent models are extensively used to assess the biochemical and physiological changes associated with aging. They play a major role in the development of therapies for age-related pathologies such as Parkinson's disease. To validate the usefulness of these animal models in aging or age-related disease research, the consistency of cerebral aging processes across species must be evaluated. The dopaminergic system seems particularly susceptible to the aging process. One of the results of this susceptibility is a decline in striatal dopamine transporter (DAT) availability. Methods: We sought to ascertain whether similar age changes could be detected in-vivo in rats, using molecular imaging techniques such as single photon emission computed tomography (SPECT) with [ 123 I]FP-CIT. Results: A significant decrease of 17.21% in the striatal specific uptake ratio was observed in the aged rats with respect to the young control group. Conclusions: Our findings suggest that age-related degeneration in the nigrostriatal track is similar in humans and rats, which supports the use of this animal in models to evaluate the effect of aging on the dopaminergic system. Advances in Knowledge and Implications for patient Care: Our findings indicate that age-related degeneration in the nigrostriatal track is similar in humans and rats and that these changes can be monitored in vivo using small animal SPECT with [ 123 I]FP-CIT, which could facilitate the translational research in rat models of age related disorders of dopaminergic system

Pituitary adenylate cyclase-activating polypeptide (PACAP has a neuroprotective function in dopamine-based neurodegeneration in rat and snail parkinsonian models

Directory of Open Access Journals (Sweden)

Gabor Maasz

2017-02-01

Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP rescues dopaminergic neurons from neurodegeneration and improves motor changes induced by 6-hydroxy-dopamine (6-OHDA in rat parkinsonian models. Recently, we investigated the molecular background of the neuroprotective effect of PACAP in dopamine (DA-based neurodegeneration using rotenone-induced snail and 6-OHDA-induced rat models of Parkinson's disease. Behavioural activity, monoamine (DA and serotonin, metabolic enzyme (S-COMT, MB-COMT and MAO-B and PARK7 protein concentrations were measured before and after PACAP treatment in both models. Locomotion and feeding activity were decreased in rotenone-treated snails, which corresponded well to findings obtained in 6-OHDA-induced rat experiments. PACAP was able to prevent the behavioural malfunctions caused by the toxins. Monoamine levels decreased in both models and the decreased DA level induced by toxins was attenuated by ∼50% in the PACAP-treated animals. In contrast, PACAP had no effect on the decreased serotonin (5HT levels. S-COMT metabolic enzyme was also reduced but a protective effect of PACAP was not observed in either of the models. Following toxin treatment, a significant increase in MB-COMT was observed in both models and was restored to normal levels by PACAP. A decrease in PARK7 was also observed in both toxin-induced models; however, PACAP had a beneficial effect only on 6-OHDA-treated animals. The neuroprotective effect of PACAP in different animal models of Parkinson's disease is thus well correlated with neurotransmitter, enzyme and protein levels. The models successfully mimic several, but not all etiological properties of the disease, allowing us to study the mechanisms of neurodegeneration as well as testing new drugs. The rotenone and 6-OHDA rat and snail in vivo parkinsonian models offer an alternative method for investigation of the molecular mechanisms of neuroprotective agents, including PACAP.

Photoacoustic tomography of joints aided by an Etanercept-conjugated gold nanoparticle contrast agent-an ex vivo preliminary rat study

International Nuclear Information System (INIS)

Chamberland, David L; Agarwal, Ashish; Kotov, Nicholas; Fowlkes, J Brian; Carson, Paul L; Wang Xueding

2008-01-01

Monitoring of anti-rheumatic drug delivery in experimental models and in human diseases would undoubtedly be very helpful for both basic research and clinical management of inflammatory diseases. In this study, we have investigated the potential of an emerging hybrid imaging technology-photoacoustic tomography-in noninvasive monitoring of anti-TNF drug delivery. After the contrast agent composed of gold nanorods conjugated with Etanercept molecules was produced, ELISA experiments were performed to prove the conjugation and to show that the conjugated anti-TNF-α drug was biologically active. PAT of ex vivo rat tail joints with the joint connective tissue enhanced by intra-articularly injected contrast agent was conducted to examine the performance of PAT in visualizing the distribution of the gold-nanorod-conjugated drug in articular tissues. By using the described system, gold nanorods with a concentration down to 1 pM in phantoms or 10 pM in biological tissues can be imaged with good signal-to-noise ratio and high spatial resolution. This study demonstrates the feasibility of conjugating TNF antagonist pharmaceutical preparations with gold nanorods, preservation of the mechanism of action of TNF antagonist along with preliminary evaluation of novel PAT technology in imaging optical contrast agents conjugated with anti-rheumatic drugs. Further in vivo studies on animals are warranted to test the specific binding between such conjugates and targeted antigen in joint tissues affected by inflammation

Capsaicin pretreatment enhanced the bioavailability of fexofenadine in rats by P-glycoprotein modulation: in vitro, in situ and in vivo evaluation.

Science.gov (United States)

Bedada, Satish Kumar; Appani, Ramgopal; Boga, Praveen Kumar

2017-06-01

Capsaicin is the main pungent principle present in chili peppers has been found to possess P-glycoprotein (P-gp) inhibition activity in vitro, which may have the potential to modulate bioavailability of P-gp substrates. Therefore, purpose of this study was to evaluate the effect of capsaicin on intestinal absorption and bioavailability of fexofenadine, a P-gp substrate in rats. The mechanistic evaluation was determined by non-everted sac and intestinal perfusion studies to explore the intestinal absorption of fexofenadine. These results were confirmed by an in vivo pharmacokinetic study of oral administered fexofenadine in rats. The intestinal transport and apparent permeability (P app ) of fexofenadine were increased significantly by 2.8 and 2.6 fold, respectively, in ileum of capsaicin treated rats when compared to control group. Similarly, absorption rate constant (K a ), fraction absorbed (F ab ) and effective permeability (P eff ) of fexofenadine were increased significantly by 2.8, 2.9 and 3.4 fold, respectively, in ileum of rats pretreated with capsaicin when compared to control group. In addition, maximum plasma concentration (C max ) and area under the concentration-time curve (AUC) were increased significantly by 2.3 and 2.4 fold, respectively, in rats pretreated with capsaicin as compared to control group. Furthermore, obtained results in rats pretreated with capsaicin were comparable to verapamil (positive control) treated rats. Capsaicin pretreatment significantly enhanced the intestinal absorption and bioavailability of fexofenadine in rats likely by inhibition of P-gp mediated cellular efflux, suggesting that the combined use of capsaicin with P-gp substrates may require close monitoring for potential drug interactions.

Effects of curcumin-loaded PLGA nanoparticles on the RG2 rat glioma model.

Science.gov (United States)

Orunoğlu, Merdan; Kaffashi, Abbas; Pehlivan, Sibel Bozdağ; Şahin, Selma; Söylemezoğlu, Figen; Oğuz, Kader Karli; Mut, Melike

2017-09-01

Curcumin, the active ingredient of turmeric, has a remarkable antitumor activity against various cancers, including glioblastoma. However, it has poor absorption and low bioavailability; thus, to cross the blood-brain barrier and reach tumor tissue, it needs to be transferred to tumor site by special drug delivery systems, such as nanoparticles. We aimed to evaluate the antitumor activity of curcumin on glioblastoma tissue in the rat glioma-2 (RG2) tumor model when it is loaded on poly(lactic-co-glycolic acid)-1,2-distearoyl-glycerol-3-phospho-ethanolamine-N-[methoxy (polyethylene glycol)-2000] ammonium salt (PLGA-DSPE-PEG) hybrid nanoparticles. Glioblastoma was induced in 42 adult female Wistar rats (250-300g) by RG2 tumor model. The curcumin-loaded nanoparticles were injected by intravenous (n=6) or intratumoral route (n=6). There were five control groups, each containing six rats. First control group was not applied any treatment. The remaining four control groups were given empty nanoparticles or curcumin alone by intravenous or intratumoral route, respectively. The change in tumor volume was assessed by magnetic resonance imaging and histopathology before and 5days after drug injections. Tumor size decreased significantly after 5days of intratumoral injection of curcumin-loaded nanoparticle (from 66.6±44.6 to 34.9±21.7mm 3 , p=0.028), whereas it significantly increased in nontreated control group (from 33.9±21.3 to 123.7±41.1mm 3 , p=0.036) and did not significantly change in other groups (p>0.05 for all). In this in vivo experimental model, intratumoral administration of curcumin-loaded PLGA-DSPE-PEG hybrid nanoparticles was effective against glioblastoma. Curcumine-loaded nanoparticles may have potential application in chemotherapy of glioblastoma. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of adulterants in a Chinese herbal medicine by LC-HRMS and LC-MS-SPE/NMR and comparative in vivo study with standards in a hypertensive rat model

DEFF Research Database (Denmark)

Kesting, Julie Regitze; Huang, JingQi; Sørensen, Dan

2010-01-01

Based on anecdotal evidence of anti-hypertensive effect of Gold Nine Soft Capsules, an in vivo study of this complex Chinese "herbal-based" medicine was initiated. Dosage of the content of Gold Nine capsules in spontaneous hypertensive rats showed a remarkably good effect. This led to further...... of a combination of commercially purchased standards was shown to be equivalent to that of the capsule content. Adulteration of herbal remedies and dietary supplements with synthetic drugs is an increasing problem that may lead to serious adverse effects. LC-MS-SPE/NMR as a method for the rapid identification...

In vivo rat deep brain imaging using photoacoustic computed tomography (Conference Presentation)

Science.gov (United States)

Lin, Li; Li, Lei; Zhu, Liren; Hu, Peng; Wang, Lihong V.

2017-03-01

The brain has been likened to a great stretch of unknown territory consisting of a number of unexplored continents. Small animal brain imaging plays an important role charting that territory. By using 1064 nm illumination from the side, we imaged the full coronal depth of rat brains in vivo. The experiment was performed using a real-time full-ring-array photoacoustic computed tomography (PACT) imaging system, which achieved an imaging depth of 11 mm and a 100 μm radial resolution. Because of the fast imaging speed of the full-ring-array PACT system, no animal motion artifact was induced. The frame rate of the system was limited by the laser repetition rate (50 Hz). In addition to anatomical imaging of the blood vessels in the brain, we continuously monitored correlations between the two brain hemispheres in one of the coronal planes. The resting states in the coronal plane were measured before and after stroke ligation surgery at a neck artery.

Development of a population pharmacokinetic model to predict brain distribution and dopamine D2 receptor occupancy of raclopride in non-anesthetized rat.

Science.gov (United States)

Wong, Yin Cheong; Ilkova, Trayana; van Wijk, Rob C; Hartman, Robin; de Lange, Elizabeth C M

2018-01-01

Raclopride is a selective antagonist of the dopamine D2 receptor. It is one of the most frequently used in vivo D2 tracers (at low doses) for assessing drug-induced receptor occupancy (RO) in animals and humans. It is also commonly used as a pharmacological blocker (at high doses) to occupy the available D2 receptors and antagonize the action of dopamine or drugs on D2 in preclinical studies. The aims of this study were to comprehensively evaluate its pharmacokinetic (PK) profiles in different brain compartments and to establish a PK-RO model that could predict the brain distribution and RO of raclopride in the freely moving rat using a LC-MS based approach. Rats (n=24) received a 10-min IV infusion of non-radiolabeled raclopride (1.61μmol/kg, i.e. 0.56mg/kg). Plasma and the brain tissues of striatum (with high density of D2 receptors) and cerebellum (with negligible amount of D2 receptors) were collected. Additional microdialysis experiments were performed in some rats (n=7) to measure the free drug concentration in the extracellular fluid of the striatum and cerebellum. Raclopride concentrations in all samples were analyzed by LC-MS. A population PK-RO model was constructed in NONMEM to describe the concentration-time profiles in the unbound plasma, brain extracellular fluid and brain tissue compartments and to estimate the RO based on raclopride-D2 receptor binding kinetics. In plasma raclopride showed a rapid distribution phase followed by a slower elimination phase. The striatum tissue concentrations were consistently higher than that of cerebellum tissue throughout the whole experimental period (10-h) due to higher non-specific tissue binding and D2 receptor binding in the striatum. Model-based simulations accurately predicted the literature data on rat plasma PK, brain tissue PK and D2 RO at different time points after intravenous or subcutaneous administration of raclopride at tracer dose (RO 30%). For the first time a predictive model that could describe

Nanodiamonds for Medical Applications: Interaction with Blood in Vitro and in Vivo.

Science.gov (United States)

Tsai, Lin-Wei; Lin, Yu-Chung; Perevedentseva, Elena; Lugovtsov, Andrei; Priezzhev, Alexander; Cheng, Chia-Liang

2016-07-12

Nanodiamonds (ND) have emerged to be a widely-discussed nanomaterial for their applications in biological studies and for medical diagnostics and treatment. The potentials have been successfully demonstrated in cellular and tissue models in vitro. For medical applications, further in vivo studies on various applications become important. One of the most challenging possibilities of ND biomedical application is controllable drug delivery and tracing. That usually assumes ND interaction with the blood system. In this work, we study ND interaction with rat blood and analyze how the ND surface modification and coating can optimize the ND interaction with the blood. It was found that adsorption of a low concentration of ND does not affect the oxygenation state of red blood cells (RBC). The obtained in vivo results are compared to the results of in vitro studies of nanodiamond interaction with rat and human blood and blood components, such as red blood cells and blood plasma. An in vivo animal model shows ND injected in blood attach to the RBC membrane and circulate with blood for more than 30 min; and ND do not stimulate an immune response by measurement of proinflammatory cytokine TNF-α with ND injected into mice via the caudal vein. The results further confirm nanodiamonds' safety in organisms, as well as the possibility of their application without complicating the blood's physiological conditions.

Nanodiamonds for Medical Applications: Interaction with Blood in Vitro and in Vivo

Directory of Open Access Journals (Sweden)

Lin-Wei Tsai

2016-07-01

Full Text Available Nanodiamonds (ND have emerged to be a widely-discussed nanomaterial for their applications in biological studies and for medical diagnostics and treatment. The potentials have been successfully demonstrated in cellular and tissue models in vitro. For medical applications, further in vivo studies on various applications become important. One of the most challenging possibilities of ND biomedical application is controllable drug delivery and tracing. That usually assumes ND interaction with the blood system. In this work, we study ND interaction with rat blood and analyze how the ND surface modification and coating can optimize the ND interaction with the blood. It was found that adsorption of a low concentration of ND does not affect the oxygenation state of red blood cells (RBC. The obtained in vivo results are compared to the results of in vitro studies of nanodiamond interaction with rat and human blood and blood components, such as red blood cells and blood plasma. An in vivo animal model shows ND injected in blood attach to the RBC membrane and circulate with blood for more than 30 min; and ND do not stimulate an immune response by measurement of proinflammatory cytokine TNF-α with ND injected into mice via the caudal vein. The results further confirm nanodiamonds’ safety in organisms, as well as the possibility of their application without complicating the blood’s physiological conditions.

XYLITOL IMPROVES ANTI-OXIDATIVE DEFENSE SYSTEM IN SERUM, LIVER, HEART, KIDNEY AND PANCREAS OF NORMAL AND TYPE 2 DIABETES MODEL OF RATS.

Science.gov (United States)

Chukwuma, Chika Ifeanyi; Islam, Shahidul

2017-05-01

The present study investigated the anti-oxidative effects of xylitol both in vitro and in vivo in normal and type 2 diabetes (T2D) rat model. Free radical scavenging and ferric reducing potentials of different concentrations of xylitol were investigated in vitro. For in vivo study, six weeks old male Sprague-Dawley rats were divided into four groups, namely: Normal Control (NC), Diabetic Control (DBC), Normal Xylitol (NXYL) and Diabetic Xylitol (DXYL). T2D was induced in the DBC and DXYL groups. After the confirmation of diabetes, a 10% xylitol solution was supplied instead of drinking water to NXYL and DXYL, while normal drinking water was supplied to NC and DBC ad libitum. After five weeks intervention period, the animals were sacri- ficed and thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) concentrations as well as superoxide dismutase, catalase glutathione reductase and glutathione peroxidase activities were determined in the liver, heart, kidney, pancreatic tissues and serum samples. Xylitol exhibited significant (p foods and food products.

Activation of muscarinic receptors protects against retinal neurons damage and optic nerve degeneration in vitro and in vivo models.

Science.gov (United States)

Tan, Pan-Pan; Yuan, Hai-Hong; Zhu, Xu; Cui, Yong-Yao; Li, Hui; Feng, Xue-Mei; Qiu, Yu; Chen, Hong-Zhuan; Zhou, Wei

2014-03-01

Muscarinic acetylcholine receptor agonist pilocarpine reduces intraocular pressure (IOP) of glaucoma mainly by stimulating ciliary muscle contraction and then increasing aqueous outflow. It is of our great interest to know whether pilocarpine has the additional properties of retinal neuroprotection independent of IOP lowering in vitro and in vivo models. In rat primary retinal cultures, cell viability was measured using an MTT assay and the trypan blue exclusion method, respectively. Retinal ganglion cells (RGCs) were identified by immunofluorescence and quantified by flow cytometry. For the in vivo study, the retinal damage after retinal ischemia/reperfusion injury in rats was evaluated by histopathological study using hematoxylin and eosin staining, transmission electron microscopy, and immunohistochemical study on cleaved caspase-3, caspase-3, and ChAT. Pretreatment of pilocarpine attenuated glutamate-induced neurotoxicity of primary retinal neurons in a dose-dependent manner. Protection of pilocarpine in both retinal neurons and RGCs was largely abolished by the nonselective muscarinic receptor antagonist atropine and the M1-selective muscarinic receptor antagonist pirenzepine. After ischemia/reperfusion injury in retina, the inner retinal degeneration occurred including ganglion cell layer thinning and neuron lost, and the optic nerve underwent vacuolar changes. These degenerative changes were significantly lessened by topical application of 2% pilocarpine. In addition, the protective effect of pilocarpine on the ischemic rat retina was favorably reflected by downregulating the expression of activated apoptosis marker cleaved caspase-3 and caspase-3 and upregulating the expression of cholinergic cell marker ChAT. Taken together, this highlights pilocarpine through the activation of muscarinic receptors appear to afford significant protection against retinal neurons damage and optic nerve degeneration at clinically relevant concentrations. These data also

Effects of the gastric juice injection pattern and contraction frequency on the digestibility of casein powder suspensions in an in vitro dynamic rat stomach made with a 3D printed model.

Science.gov (United States)

Zhang, Xiaoai; Liao, Zhenkai; Wu, Peng; Chen, Liding; Chen, Xiao Dong

2018-04-01

Previously, we have prepared a version of the dynamic in vitro rat stomach system (DIVRS-II or Biomimic Rat II). It was constructed and tested by showing similar digestive behaviors with those occurred in vivo. In the present work, a 3D-printed plastic mold was employed to create highly repeatable silicone rat stomach model. It has been seen to have shortened the time to handcraft a model like that used in DIVRS-II. The maximum mechanical force of the current stomach model generated by rolling extrusion is found to be more stable probably due to the more uniform wall thickness of the new model. Then the effects of the simulated gastric secretion patterns and contraction frequency of the system on the in vitro digestibility of casein powder suspensions were investigated. The results have shown that the location of the gastric secretion injection has an impact on experimental digestibility. The position of rolling-extrusion area, established at the central part of glandular portion (stomach B), displayed the highest digestibility compared to that at the other locations. Furthermore, the extent of digestion was positively correlated with the contraction frequency of the model stomach system, with the maximum frequency of 12cpm giving the highest digestibility. This highest digestibility is almost the same as the average value found in vivo. The better digestive performance produced by optimizing the gastric secretion pattern and contraction frequency may be both resulted from the improved mixing efficiency of the food matrix with digestive juice. This study shows that it is possible to achieve what in vivo in a simulated digestion device, which may be used for future food and nutrition studies in vitro. Copyright © 2018 Elsevier Ltd. All rights reserved.

Actions of p-synephrine on hepatic enzyme activities linked to carbohydrate metabolism and ATP levels in vivo and in the perfused rat liver.

Science.gov (United States)

Maldonado, Marcos Rodrigues; Bracht, Lívia; de Sá-Nakanishi, Anacharis Babeto; Corrêa, Rúbia Carvalho Gomes; Comar, Jurandir Fernando; Peralta, Rosane Marina; Bracht, Adelar

2018-01-01

p-Synephrine is one of the main active components of the fruit of Citrus aurantium (bitter orange). Extracts of the bitter orange and other preparations containing p-synephrine have been used worldwide to promote weight loss and for sports performance. The purpose of the study was to measure the action of p-synephrine on hepatic enzyme activities linked to carbohydrate and energy metabolism and the levels of adenine mononucleotides. Enzymes and adenine mononucleotides were measured in the isolated perfused rat liver and in vivo after oral administration of the drug (50 and 300 mg/kg) by using standard techniques. p-Synephrine increased the activity of glycogen phosphorylase in vivo and in the perfused liver. It decreased, however, the activities of pyruvate kinase and pyruvate dehydrogenase also in vivo and in the perfused liver. p-Synephrine increased the hepatic pools of adenosine diphosphate and adenosine triphosphate. Stimulation of glycogen phosphorylase is consistent with the reported increased glycogenolysis in the perfused liver and increased glycemia in rats. The decrease in the pyruvate dehydrogenase activity indicates that p-synephrine is potentially capable of inhibiting the transformation of carbohydrates into lipids. The capability of increasing the adenosine triphosphate-adenosine diphosphate pool indicates a beneficial effect of p-synephrine on the cellular energetics. Copyright © 2017 John Wiley & Sons, Ltd.

Interleukin-1 beta induced transient diabetes mellitus in rats. A model of the initial events in the pathogenesis of insulin-dependent diabetes mellitus?

DEFF Research Database (Denmark)

Reimers, J I

1998-01-01

When aiming at preventing IDDM in man, knowledge of the molecular mechanisms leading to beta cell destruction may facilitate identification of new possible intervention modalities. A model of IDDM pathogenesis in man suggests that cytokines, and IL-1 in particular, are of major importance...... of preventing IDDM in man, the aim af this review was to investigate the effects of rhIL-1 beta on beta-cell function and viability in normal rats. This review discussed 1) the pharmacokinetics of IL-1 beta in rats as the basis for choice of route of administration and dose of rhIL-1 beta, 2) the effects...... and molecular mechanisms of IL-1 beta on temperature and food intake used as control parameters for successful injection of rhIL-1 beta in rats, 3) the effects of one or more injection of IL-1 beta on rat beta cell function, 4) the molecular mechanisms leading to IL-1 beta induced beta cell inhibition in vivo...

The hTH-GFP reporter rat model for the study of Parkinson's disease.

Directory of Open Access Journals (Sweden)

Lorraine Iacovitti

Full Text Available Parkinson disease (PD is the second leading neurodegenerative disease in the US. As there is no known cause or cure for PD, researchers continue to investigate disease mechanisms and potential new therapies in cell culture and in animal models of PD. In PD, one of the most profoundly affected neuronal populations is the tyrosine hydroxylase (TH-expressing dopaminergic (DA neurons of the substantia nigra pars compacta (SNpc. These DA-producing neurons undergo degeneration while neighboring DA-producing cells of the ventral tegmental area (VTA are largely spared. To aid in these studies, The Michael J. Fox Foundation (MJFF partnered with Thomas Jefferson University and Taconic Inc. to generate new transgenic rat lines carrying the human TH gene promoter driving EGFP using a 11 kb construct used previously to create a hTH-GFP mouse reporter line. Of the five rat founder lines that were generated, three exhibited high level specific GFP fluorescence in DA brain structures (ie. SN, VTA, striatum, olfactory bulb, hypothalamus. As with the hTH-GFP mouse, none of the rat lines exhibit reporter expression in adrenergic structures like the adrenal gland. Line 12141, with its high levels of GFP in adult DA brain structures and minimal ectopic GFP expression in non-DA structures, was characterized in detail. We show here that this line allows for anatomical visualization and microdissection of the rat midbrain into SNpc and/or VTA, enabling detailed analysis of midbrain DA neurons and axonal projections after toxin treatment in vivo. Moreover, we further show that embryonic SNpc and/or VTA neurons, enriched by microdissection or FACS, can be used in culture or transplant studies of PD. Thus, the hTH-GFP reporter rat should be a valuable tool for Parkinson's disease research.

In vivo metabolism of CCl4 by rats pretreated with chlordecone, mirex, or phenobarbital

International Nuclear Information System (INIS)

Mehendale, H.M.; Klingensmith, J.S.

1988-01-01

The propensity of chlordecone (CD) to potentiate hepatotoxic and lethal effects of CCl4 is well established. Mirex (M), a close structural analogue of CD, or phenobarbital (PB), powerful inducers of hepatic microsomal drug metabolizing enzymes, are much weaker potentiators of CCl4 toxicity. The purpose of this study was to test the possibility that CD potentiates the toxicity of CCl4 by increasing the metabolism of CCl4 to a greater degree than either PB or M. We compared the in vivo metabolism of CCl4 in rats pretreated with CD, M, or PB, by measuring the hepatic content of 14CCl4, the expiration of 14CCl4, expiration of 14CCl4-derived 14CO2, and lipid peroxidation. Male Sprague-Dawley rats (250-270 g) were pretreated with a single oral dose of CD (10 mg/kg), M (10 mg/kg), or corn oil vehicle (1 ml/kg). PB pretreatment consisted of an ip injection of sodium PB (80 mg/kg) in saline (0.9%) for 2 successive days. Twenty-four hours later, 14CCl4 (0.1 ml/kg; sp act: 0.04 mCi/mmol) was administered ip in corn oil and the radioactivity present in the expired air was collected for 6 hr. Excretion of the parent compound as represented by the 14C label in the toluene trap was unchanged by any of the pretreatments. Expiration of 14CO2 measured during the 6 hr after CCl4 administration was increased in animals pretreated with PB or CD. In vivo lipid peroxidation measured as diene conjugation in lipids extracted from the livers was increased to a similar extent in animals pretreated with PB and CD, whereas the serum transaminases (ALT, AST) were significantly elevated only in animals pretreated with CD.M did not affect 14CO2 production and was without a significant effect on the lipid peroxidation

Evaluation of hypoxic tissue dynamics with 18F-FMISO PET in a rat model of permanent cerebral ischemia.

Science.gov (United States)

Rojas, Santiago; Herance, José Raul; Abad, Sergio; Jiménez, Xavier; Pareto, Deborah; Ruiz, Alba; Torrent, Èlia; Figueiras, Francisca P; Popota, Foteini; Fernández-Soriano, Francisco J; Planas, Anna M; Gispert, Juan D

2011-06-01

[¹⁸F]Fluoromisonidazole (¹⁸F-FMISO) is a nitroimidazole derivative that has been proposed as a positron emission tomography (PET) radiotracer to detect hypoxic tissue in vivo. This compound accumulates in hypoxic but viable tissue and may be a good candidate for evaluating the ischemic penumbra. We evaluated the time course of ¹⁸F-FMISO uptake using PET in a rat model of permanent cerebral ischemia and the correlation with histological changes. Rats (n = 14) were subjected to permanent ischemia by intraluminal occlusion of the middle cerebral artery in order to assess by PET the uptake of ¹⁸F-FMISO at various times over 24 h following ischemia. The PET results were compared to histological changes with Nissl and 2,3,5 triphenyltetrazolium chloride staining. Elevated uptake of ¹⁸F-FMISO was detected in the infarcted area up to 8 h after occlusion but was no longer detected at 24 h, a time point coincident with pan necrosis of the tissue. Our findings suggest that salvageable tissue persists for up to 8 h in this rat model of brain ischemia. We propose ¹⁸F-FMISO PET as a tool for evaluating the ischemic penumbra after cerebral ischemia.

The impact of standing wave effects on transcranial focused ultrasound disruption of the blood-brain barrier in a rat model

International Nuclear Information System (INIS)

O'Reilly, Meaghan A; Huang Yuexi; Hynynen, Kullervo

2010-01-01

Microbubble-mediated disruption of the blood-brain barrier (BBB) for targeted drug delivery using focused ultrasound shows great potential as a therapy for a wide range of brain disorders. This technique is currently at the pre-clinical stage and important work is being conducted in animal models. Measurements of standing waves in ex vivo rat skulls were conducted using an optical hydrophone and a geometry dependence was identified. Standing waves could not be eliminated through the use of swept frequencies, which have been suggested to eliminate standing waves. Definitive standing wave patterns were detected in over 25% of animals used in a single study. Standing waves were successfully eliminated using a wideband composite sharply focused transducer and a reduced duty cycle. The modified pulse parameters were used in vivo to disrupt the BBB in a rat indicating that, unlike some other bioeffects, BBB disruption is not dependent on standing wave conditions. Due to the high variability of standing waves and the inability to correctly estimate in situ pressures given standing wave conditions, attempts to minimize standing waves should be made in all future work in this field to ensure that results are clinically translatable.

Investigation of the in vivo antioxidative activity of Cynara scolymus (artichoke) leaf extract in the streptozotocin-induced diabetic rat.

Science.gov (United States)

Magielse, Joanna; Verlaet, Annelies; Breynaert, Annelies; Keenoy, Begoña Manuel Y; Apers, Sandra; Pieters, Luc; Hermans, Nina

2014-01-01

The in vivo antioxidant activity of a quantified leaf extract of Cynara scolymus (artichoke) was studied. The aqueous artichoke leaf extract (ALE), containing 1.5% caffeoylquinic acid with chlorogenic acid being most abundant (0.30%), and luteolin-7-O-glucoside as major flavonoid (0.15%), was investigated by evaluating the effect on different oxidative stress biomarkers, after 3 wk oral supplementation in the streptozotocin-induced diabetic rat model. Apart from two test groups (0.2 g ALE/kg BW/day and 1 g ALE/kg BW/day, where BW is body weight), a healthy control group, untreated oxidative stress group, and vitamin E treated group (positive control) were included. A 0.2 g/kg BW/day of ALE decreased oxidative stress: malondialdehyde and 8-hydroxydeoxyguanosine levels significantly diminished, whereas erythrocyte glutathione levels significantly increased. A 1.0 g/kg BW/day ALE did not show higher antioxidant activity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rats classified as low or high cocaine locomotor responders: A unique model involving striatal dopamine transporters that predicts cocaine addiction-like behaviors

Science.gov (United States)

Yamamoto, Dorothy J.; Nelson, Anna M.; Mandt, Bruce H.; Larson, Gaynor A.; Rorabaugh, Jacki M.; Ng, Christopher M.C.; Barcomb, Kelsey M.; Richards, Toni L.; Allen, Richard M.; Zahniser, Nancy R.

2013-01-01

Individual differences are a hallmark of drug addiction. Here, we describe a rat model based on differential initial responsiveness to low dose cocaine. Despite similar brain cocaine levels, individual outbred Sprague-Dawley rats exhibit markedly different magnitudes of acute cocaine-induced locomotor activity and, thereby, can be classified as low or high cocaine responders (LCRs or HCRs). LCRs and HCRs differ in drug-induced, but not novelty-associated, hyperactivity. LCRs have higher basal numbers of striatal dopamine transporters (DATs) than HCRs and exhibit marginal cocaine inhibition of in vivo DAT activity and cocaine-induced increases in extracellular DA. Importantly, lower initial cocaine response predicts greater locomotor sensitization, conditioned place preference and greater motivation to self-administer cocaine following low dose acquisition. Further, outbred Long-Evans rats classified as LCRs, versus HCRs, are more sensitive to cocaine’s discriminative stimulus effects. Overall, results to date with the LCR/HCR model underscore the contribution of striatal DATs to individual differences in initial cocaine responsiveness and the value of assessing the influence of initial drug response on subsequent expression of addiction-like behaviors. PMID:23850581

In vivo metabolism of cannabinol by the mouse and rat and a comparison with a metabolism of delta 1-tetrahydrocannabinol and cannabidiol.

Science.gov (United States)

Harvey, D J; Martin, B R; Paton, W D

1977-12-01

The in vivo liver metabolism of cannabinol has been studied in the mouse and rat by combined gas chromatography and mass spectrometry. Cannabinol glucuronide was the major metabolite of cannabinol in the mouse and was accompanied by relatively large amounts of 7-hydroxycannabinol, cannabinol-7-oic acid and their corresponding glucuronide conjugates. Lower concentrations of glucuronides were found in the rat. Two series of disubstituted metabolites were found containing either a 7-hydroxyl or a 7-carboxylic acid group and a second hydroxyl group in the 1 inch-4 inch positions of the sidechain. These were of low concentration in the mouse but higher in the rat; 1 inch-hydroxy metabolites were particularly abundant in the latter species. Also found in the rat livers were small amounts of sidechain monohydroxy metabolites and larger quantities of 4 inches, 5 inches-bisnorcannabinol-3 inches-oic acid; these were absent in the mouse. The metabolites were identified using the trimethylsilyl (TMS), [2H9] TMS and methyl ester-TMS derivatives, and by reduction of acid metabolites with lithium aluminium deuteride to the corresponding alcohols.

Origin and characterization of retrograde labeled neurons supplying the rat urethra using fiberoptic confocal fluorescent microscopy in vivo and immunohistochemistry.

Science.gov (United States)

Lee, Keon-Cheol; Sharma, Seema; Tuttle, Jeremy B; Steers, William D

2010-10-01

Autonomic innervation of urethral smooth muscle may influence urinary continence after prostatectomy. It is unclear whether the cavernous nerves carry fibers that influence continence. Using a retrograde axonal tracer combined with real-time in vivo imaging and ex vivo immunohistochemistry we determined the course and type of neurons supplying urethral smooth muscle distal to the prostate in the rat. We injected the retrograde axonal tracers cholera toxin B fragment-Alexa Fluor 488 and Fast Blue in the distal urethral smooth muscle in 10 rats each. Five days later the cavernous nerves and pelvic ganglion were imaged using fiberoptic confocal fluorescence microscopy (cholera toxin B fragment-Alexa Fluor 488) or harvested for immunohistochemistry (Fast Blue). Dual immunofluorescence of Fast Blue neurons with tyrosine hydroxylase or neuronal nitric oxide synthase was done to characterize neurons as noradrenergic or nitrergic. To ascertain whether the cavernous nerves contain fibers to the urethra that originate in the pelvic ganglia we cut the cavernous nerves with their ancillary branches in 3 rats and imaged them for Fast Blue. Fluorescent neurons and axons were detected in cavernous nerves and the pelvic ganglion. Few neurons were seen in rats with cavernous nerve section. Of urethral neurons 53.1% showed neuronal nitric oxide synthase positivity while 40.6% were immunoreactive for tyrosine hydroxylase. About 6.2% of urethral neurons failed to show tyrosine hydroxylase or neuronal nitric oxide synthase immunoreactivity. Most of the autonomic innervation to the urethra beyond the prostatic apex travels in the cavernous nerves. Many nerves may be parasympathetic based on neuronal nitric oxide synthase immunoreactivity. Nerves supplying the urethra outside the cavernous nerves may course posterior to the prostate. Along with afferent fibers, tyrosine hydroxylase immunoreactivity expressing neuron fibers, ie noradrenergic nerves, traveling in the cavernous nerves may

Evaluation of anti-urolithiatic and diuretic activities of watermelon (Citrullus lanatus) using in vivo and in vitro experiments.

Science.gov (United States)

Siddiqui, Waqar Ahmed; Shahzad, Muhammad; Shabbir, Arham; Ahmad, Ali

2018-01-01

Traditionally, Citrullus lanatus is known to have protective properties in kidney diseases and for having the ability to clear urine. Current study aims to validate the traditional uses of C. lanatus by evaluation of anti-urolithiatic and diuretic activities using in vivo and in vitro experiments. Male Wistar rats were used for in vivo anti-urolithiatic and diuretic activities. Supersaturated solution of calcium and oxalate was used for in vitro crystallization study. Hematoxylin & eosin staining was used for histopathological evaluation of kidney. In the in vivo rat model of urolithiasis, the pulp extract reduced calcium oxalate (CaOX) crystal count in both kidney and urine. The pulp extract also increased the urinary pH and output, and prevented the weight loss. Serum analysis showed elevation in creatinine clearance and reduction in urea and creatinine levels. Urinary analysis demonstrated that pulp extract restored altered phosphate, calcium, oxalate, and citrate levels. In the in vivo rat model of diuresis; the pulp extract produced diuresis, reduced serum chloride levels, and elevated urinary sodium and chloride levels. In the in vitro crystallization experiment, pulp extract inhibited the aggregation phase. Seed extract failed to show any convincing results. GC-MS analysis revealed the presence of steroids and alkanes as the major constituents of pulp extract, which might be responsible for anti-urolithiatic activity; however, further studies are required for isolation and identification of active constituents. Current study validated the traditional uses of watermelon and demonstrated that pulp extract possessed significant anti-urolithiatic and diuretic activities. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Elucidating the in vivo fate of nanocrystals using a physiologically based pharmacokinetic model: a case study with the anticancer agent SNX-2112

Directory of Open Access Journals (Sweden)

Dong D

2015-03-01

Full Text Available Dong Dong,1* Xiao Wang,1* Huailing Wang,1 Xingwang Zhang,2 Yifei Wang,1 Baojian Wu2 1Guangzhou Jinan Biomedicine Research and Development Center, 2Division of Pharmaceutics, College of Pharmacy, Jinan University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Introduction: SNX-2112 is a promising anticancer agent but has poor solubility in both water and oil. In the study reported here, we aimed to develop a nanocrystal formulation for SNX-2112 and to determine the pharmacokinetic behaviors of the prepared nanocrystals. Methods: Nanocrystals of SNX-2112 were prepared using the wet-media milling technique and characterized by particle size, differential scanning calorimetry, drug release, etc. Physiologically based pharmacokinetic (PBPK modeling was undertaken to evaluate the drug’s disposition in rats following administration of drug cosolvent or nanocrystals. Results: The optimized SNX-2112 nanocrystals (with poloxamer 188 as the stabilizer were 203 nm in size with a zeta potential of -11.6 mV. In addition, the nanocrystals showed a comparable release profile to the control (drug cosolvent. Further, the rat PBPK model incorporating the parameters of particulate uptake (into the liver and spleen and of in vivo drug release was well fitted to the experimental data following administration of the drug nanocrystals. The results reveal that the nanocrystals rapidly released drug molecules in vivo, accounting for their cosolvent-like pharmacokinetic behaviors. Due to particulate uptake, drug accumulation in the liver and spleen was significant at the initial time points (within 1 hour. Conclusion: The nanocrystals should be a good choice for the systemic delivery of the poorly soluble drug SNX-2112. Also, our study contributes to an improved understanding of the in vivo fate of nanocrystals. Keywords: intravenous delivery, PBPK, tissue distribution, poloxamer 188

Effect of Microenvironment on Differentiation of Human Umbilical Cord Mesenchymal Stem Cells into Hepatocytes In Vitro and In Vivo

Directory of Open Access Journals (Sweden)

Gai Xue

2016-01-01

Full Text Available Human umbilical cord-derived mesenchymal stem cells (hUCMSCs are considered to be an ideal cell source for cell therapy of many diseases. The aim of this study was to investigate the contribution of the microenvironment to the hepatic differentiation potential of hUCMSCs in vitro and in vivo and to explore their therapeutic use in acute liver injury in rats. We established a new model to simulate the liver tissue microenvironment in vivo using liver homogenate supernatant (LHS in vitro. This induced environment could drive hUCMSCs to differentiate into hepatocyte-like cells within 7 days. The differentiated cells expressed hepatocyte-specific markers and demonstrated hepatocellular functions. We also injected hUCMSCs into rats with CCl4-induced acute hepatic injury. The hUCMSCs were detected in the livers of recipient rats and expressed the human hepatocyte-specific markers, suggesting that hUCMSCs could differentiate into hepatocyte-like cells in vivo in the liver tissue microenvironment. Levels of biochemistry markers improved significantly after transplantation of hUCMSCs compared with the nontransplantation group (P<0.05. In conclusion, this study demonstrated that the liver tissue microenvironment may contribute to the differentiation of hUCMSCs into hepatocytes both in vitro and in vivo.

Effect of Microenvironment on Differentiation of Human Umbilical Cord Mesenchymal Stem Cells into Hepatocytes In Vitro and In Vivo

Science.gov (United States)

Xue, Gai; Han, Xiaolei; Ma, Xin; Wu, Honghai; Qin, Yabin; Liu, Jianfang; Hu, Yuqin; Hong, Yang; Hou, Yanning

2016-01-01

Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) are considered to be an ideal cell source for cell therapy of many diseases. The aim of this study was to investigate the contribution of the microenvironment to the hepatic differentiation potential of hUCMSCs in vitro and in vivo and to explore their therapeutic use in acute liver injury in rats. We established a new model to simulate the liver tissue microenvironment in vivo using liver homogenate supernatant (LHS) in vitro. This induced environment could drive hUCMSCs to differentiate into hepatocyte-like cells within 7 days. The differentiated cells expressed hepatocyte-specific markers and demonstrated hepatocellular functions. We also injected hUCMSCs into rats with CCl4-induced acute hepatic injury. The hUCMSCs were detected in the livers of recipient rats and expressed the human hepatocyte-specific markers, suggesting that hUCMSCs could differentiate into hepatocyte-like cells in vivo in the liver tissue microenvironment. Levels of biochemistry markers improved significantly after transplantation of hUCMSCs compared with the nontransplantation group (P < 0.05). In conclusion, this study demonstrated that the liver tissue microenvironment may contribute to the differentiation of hUCMSCs into hepatocytes both in vitro and in vivo. PMID:27088093

Muscle-Driven In Vivo Nanogenerator

KAUST Repository

Li, Zhou

2010-05-05

(Figure Presented) A nanogenerator based on a single piezoelectric fine wire producing an alternating current (AC) is successfully used for the harvesting of biomechanical energy under in vivo conditions. We demonstrate the implanting and working of such a nanogenerator in a live rat where it harvests energy generated by its breathing or heart beating. This study shows the potential of applying these nanogenerators for driving in vivo nanodevices. © 2010 WILEY-VCH Verlag GmbH & Co. KCaA, Weinheim.

[123I]Epidepride neuroimaging of dopamine D2/D3 receptor in chronic MK-801-induced rat schizophrenia model

International Nuclear Information System (INIS)

Huang, Yuan-Ruei; Shih, Jun-Ming; Chang, Kang-Wei; Huang, Chieh; Wu, Yu-Lung; Chen, Chia-Chieh

2012-01-01

Purpose: [ 123 I]Epidepride is a radio-tracer with very high affinity for dopamine D 2 /D 3 receptors in brain. The importance of alteration in dopamine D 2 /D 3 receptor binding condition has been wildly verified in schizophrenia. In the present study we set up a rat schizophrenia model by chronic injection of a non-competitive NMDA receptor antagonist, MK-801, to examine if [ 123 I]epidepride could be used to evaluate the alterations of dopamine D 2 /D 3 receptor binding condition in specific brain regions. Method: Rats were given repeated injection of MK-801 (dissolved in saline, 0.3 mg/kg) or saline for 1 month. Afterwards, total distance traveled (cm) and social interaction changes were recorded. Radiochemical purity of [ 123 I]epidepride was analyzed by Radio-Thin-Layer Chromatography (chloroform: methanol, 9:1, v/v) and [ 123 I]epidepride neuroimages were obtained by ex vivo autoradiography and small animal SPECT/CT. Data obtained were then analyzed to determine the changes of specific binding ratio. Result: Chronic MK-801 treatment for a month caused significantly increased local motor activity and induced an inhibition of social interaction. As shown in [ 123 I]epidepride ex vivo autoradiographs, MK-801 induced a decrease of specific binding ratio in the striatum (24.01%), hypothalamus (35.43%), midbrain (41.73%) and substantia nigra (37.93%). In addition, [ 123 I]epidepride small animal SPECT/CT neuroimaging was performed in the striatum and midbrain. There were statistically significant decreases in specific binding ratio in both the striatum (P 123 I]epidepride is a useful radio-tracer to reveal the alterations of dopamine D 2 /D 3 receptor binding in a rat schizophrenia model and is also helpful to evaluate therapeutic effects of schizophrenia in the future.

Ex vivo exposure of bone marrow from chronic kidney disease donor rats to pravastatin limits renal damage in recipient rats with chronic kidney disease

NARCIS (Netherlands)

Koppen, A. van; Papazova, D.A.; Oosterhuis, N.R.; Gremmels, H.; Giles, R.H.; Fledderus, J.O.; Joles, J.A.; Verhaar, M.C.

2015-01-01

Introduction: Healthy bone marrow cell (BMC) infusion improves renal function and limits renal injury in a model of chronic kidney disease (CKD) in rats. However, BMCs derived from rats with CKD fail to retain beneficial effects, demonstrating limited therapeutic efficacy. Statins have been reported

Ex vivo exposure of bone marrow from chronic kidney disease donor rats to pravastatin limits renal damage in recipient rats with chronic kidney disease

NARCIS (Netherlands)

van Koppen, Arianne; Papazova, Diana A.; Oosterhuis, Nynke R.; Gremmels, Hendrik; Giles, Rachel H.; Fledderus, Joost O.; Joles, Jaap A.; Verhaar, Marianne C.

2015-01-01

INTRODUCTION: Healthy bone marrow cell (BMC) infusion improves renal function and limits renal injury in a model of chronic kidney disease (CKD) in rats. However, BMCs derived from rats with CKD fail to retain beneficial effects, demonstrating limited therapeutic efficacy. Statins have been reported

A multi-site comparison of in vivo safety pharmacology studies conducted to support ICH S7A & B regulatory submissions.

Science.gov (United States)

Ewart, Lorna; Milne, Aileen; Adkins, Debbie; Benjamin, Amanda; Bialecki, Russell; Chen, Yafei; Ericsson, Ann-Christin; Gardner, Stacey; Grant, Claire; Lengel, David; Lindgren, Silvana; Lowing, Sarah; Marks, Louise; Moors, Jackie; Oldman, Karen; Pietras, Mark; Prior, Helen; Punton, James; Redfern, Will S; Salmond, Ross; Skinner, Matt; Some, Margareta; Stanton, Andrea; Swedberg, Michael; Finch, John; Valentin, Jean-Pierre

2013-01-01

Parts A and B of the ICH S7 guidelines on safety pharmacology describe the in vivo studies that must be conducted prior to first time in man administration of any new pharmaceutical. ICH S7A requires a consideration of the sensitivity and reproducibility of the test systems used. This could encompass maintaining a dataset of historical pre-dose values, power analyses, as well as a demonstration of acceptable model sensitivity and robust pharmacological validation. During the process of outsourcing safety pharmacology studies to Charles River Laboratories, AstraZeneca set out to ensure that models were performed identically in each facility and saw this as an opportunity to review the inter-laboratory variability of these essential models. The five in vivo studies outsourced were the conscious dog telemetry model for cardiovascular assessment, the rat whole body plethysmography model for respiratory assessment, the rat modified Irwin screen for central nervous system assessment, the rat charcoal meal study for gastrointestinal assessment and the rat metabolic cage study for assessment of renal function. Each study was validated with known reference compounds and data were compared across facilities. Statistical power was also calculated for each model. The results obtained indicated that each of the studies could be performed with comparable statistical power and could achieve a similar outcome, independent of facility. The consistency of results obtained from these models across multiple facilities was high thus providing confidence that the models can be run in different facilities and maintain compliance with ICH S7A and B. Copyright © 2013 Elsevier Inc. All rights reserved.

Characterization of biological features of a rat F98 GBM model: A PET-MRI study with [18F]FAZA and [18F]FDG

International Nuclear Information System (INIS)

Belloli, Sara; Brioschi, Andrea; Politi, Letterio Salvatore; Ronchetti, Francesca; Calderoni, Sara; Raccagni, Isabella; Pagani, Antonella; Monterisi, Cristina; Zenga, Francesco; Zara, Gianpaolo; Fazio, Ferruccio; Mauro, Alessandro

2013-01-01

Introduction: The prognosis of malignant gliomas remains largely unsatisfactory for the intrinsic characteristics of the pathology and for the delayed diagnosis. Multimodal imaging based on PET and MRI may assess the dynamics of disease onset and progression allowing the validation of preclinical models of glioblastoma multiforme (GBM). The aim of this study was the characterization of a syngeneic rat model of GBM using combined in vivo imaging and immunohistochemistry. Methods: Four groups of Fischer rats were implanted in a subcortical region with increasing concentration of rat glioma F98 cells and weekly monitored with Gd-MR, [ 18 F]FDG- and [ 18 F]FAZA-PET starting one week after surgery. Different targets were evaluated on post mortem brain specimens using immunohistochemistry: VEGF, GFAP, HIF-1α, Ki-67 and nestin. Results: Imaging results indicated that tumor onset but not progression was related to the number of F98 cells. Hypoxic regions identified with [ 18 F]FAZA and high-glucose metabolism regions recognized with [ 18 F]FDG were located respectively in the core and in external areas of the tumor, with partial overlap and remodeling during disease progression. Histological and immunohistochemical analysis confirmed PET/MRI results and revealed that our model resumes biological characteristics of human GBM. IHC and PET studies showed that necrotic regions, defined on the basis of [ 18 F]FDG uptake reduction, may include hypoxic clusters of vital tumor tissue identified with [ 18 F]FAZA. This last information is particularly relevant for the identification of the target volume during image-guided radiotherapy. Conclusions: In conclusion, the combined use of PET and MRI allows in vivo monitoring of the biological modification of F98 lesions during tumor progression

Pretreatment of liver grafts in vivo by γ-aminobutyric acid receptor regulation reduces cold ischemia/warm reperfusion injury in rat

Science.gov (United States)

Hori, Tomohide; Gardner, Lindsay B.; Hata, Toshiyuki; Chen, Feng; Baine, Ann-Marie T.; Uemoto, Shinji; Nguyen, Justin H.

2014-01-01

Summary Background: Gamma-aminobutyric acid (GABA) is found throughout the body. The regulation of GABA receptor (GABAR) reduces oxidative stress (OS). Ischemia/reperfusion injury after orthotopic liver transplantation (OLT) causes OS-induced graft damage. The effects of GABAR regulation in donors in vivo were investigated. Material/Methods: Donor rats received saline, a GABAR agonist or GABAR antagonist 4 h before surgery. Recipient rats were divided into four groups according to the donor treatments: laparotomy, OLT with saline, OLT with GABAR agonist and OLT with GABAR antagonist. Histopathological, biochemical and immunohistological examinations were performed at 6, 12 and 24 h after OLT. Protein assays were performed at 6 h after OLT. The 4-hydroxynonenal (4-HNE), ataxia-telangiectasia mutated kinase (ATM), phosphorylated histone H2AX (γH2AX), phosphatidylinositol-3 kinase (PI3K), Akt and superoxide dismutase (SOD) were assessed by western blot analysis. Results: In the univariate analysis, histopathological and biochemical profiles verified that the GABAR agonist reduced graft damage. Immunohistology revealed that the GABAR agonist prevented the induction of apoptosis. Measurement of 4-4-HNE levels confirmed OS-induced damage after OLT, and the GABAR agonist improved this damage. In the γH2AX, PI3K, Akt and antioxidant enzymes (SODs), ATM and H2AX were greatly increased after OLT, and were reduced by the GABAR agonist. In the multivariate analyses between multiple groups, histopathological assessment, aspartate aminotransferase level, immunohistological examinations for apoptotic induction and γH2AX showed statistical differences. Conclusions: A specific agonist demonstrated regulation of GABAR in vivo in the liver. This activation in vivo reduced OS after OLT via the ATM/H2AX pathway. PMID:23792534

CdSe/ZnS Quantum Dots-Labeled Mesenchymal Stem Cells for Targeted Fluorescence Imaging of Pancreas Tissues and Therapy of Type 1 Diabetic Rats.

Science.gov (United States)

Liu, Haoqi; Tang, Wei; Li, Chao; Lv, Pinlei; Wang, Zheng; Liu, Yanlei; Zhang, Cunlei; Bao, Yi; Chen, Haiyan; Meng, Xiangying; Song, Yan; Xia, Xiaoling; Pan, Fei; Cui, Daxiang; Shi, Yongquan

2015-12-01

Mesenchymal stem cells (MSCs) have been used for therapy of type 1 diabetes mellitus. However, the in vivo distribution and therapeutic effects of transplanted MSCs are not clarified well. Herein, we reported that CdSe/ZnS quantum dots-labeled MSCs were prepared for targeted fluorescence imaging and therapy of pancreas tissues in rat models with type 1 diabetes. CdSe/ZnS quantum dots were synthesized, their biocompatibility was evaluated, and then, the appropriate concentration of quantum dots was selected to label MSCs. CdSe/ZnS quantum dots-labeled MSCs were injected into mouse models with type 1 diabetes via tail vessel and then were observed by using the Bruker In-Vivo F PRO system, and the blood glucose levels were monitored for 8 weeks. Results showed that prepared CdSe/ZnS quantum dots owned good biocompatibility. Significant differences existed in distribution of quantum dots-labeled MSCs between normal control rats and diabetic rats (p quantum dots-labeled MSC injection. Statistical differences existed between the blood glucose levels of the diabetic rat control group and MSC-injected diabetic rat group (p < 0.01), and the MSC-injected diabetic rat group displayed lower blood glucose levels. In conclusion, CdSe/ZnS-labeled MSCs can target in vivo pancreas tissues in diabetic rats, and significantly reduce the blood glucose levels in diabetic rats, and own potential application in therapy of diabetic patients in the near future.

Further assessment of Monkeypox Virus infection in Gambian pouched rats (Cricetomys gambianus) using in vivo bioluminescent imaging

Science.gov (United States)

Falendysz, Elizabeth; Lopera, Juan G.; Faye Lorenzsonn,; Salzer, Johanna S.; Hutson, Christina L.; Doty, Jeffrey; Gallardo-Romero, Nadia; Carroll, Darin S.; Osorio, Jorge E.; Rocke, Tonie E.

2015-01-01

Monkeypox is a zoonosis clinically similar to smallpox in humans. Recent evidence has shown a potential risk of increased incidence in central Africa. Despite attempts to isolate the virus from wild rodents and other small mammals, no reservoir host has been identified. In 2003,Monkeypox virus (MPXV) was accidentally introduced into the U.S. via the pet trade and was associated with the Gambian pouched rat (Cricetomys gambianus). Therefore, we investigated the potential reservoir competence of the Gambian pouched rat for MPXV by utilizing a combination of in vivo and in vitro methods. We inoculated three animals by the intradermal route and three animals by the intranasal route, with one mock-infected control for each route. Bioluminescent imaging (BLI) was used to track replicating virus in infected animals and virological assays (e.g. real time PCR, cell culture) were used to determine viral load in blood, urine, ocular, nasal, oral, and rectal swabs. Intradermal inoculation resulted in clinical signs of monkeypox infection in two of three animals. One severely ill animal was euthanized and the other affected animal recovered. In contrast, intranasal inoculation resulted in subclinical infection in all three animals. All animals, regardless of apparent or inapparent infection, shed virus in oral and nasal secretions. Additionally, BLI identified viral replication in the skin without grossly visible lesions. These results suggest that Gambian pouched rats may play an important role in transmission of the virus to humans, as they are hunted for consumption and it is possible for MPXV-infected pouched rats to shed infectious virus without displaying overt clinical signs.

The physiological response of obese rat model with rambutan peel extract treatment

Directory of Open Access Journals (Sweden)

Sri Rahayu Lestari

2014-09-01

Full Text Available Objective: To determine body weight gain, expression of Igf-1 and Igf-1 receptor on obese rat model treated with rambutan peel extract (RPE as a physiological response. Methods: Normal and obese rat feed with normal and high calorie diet around 1 2 weeks and continued to treat with ellagic acid, RPE 15, 30 and 60 mg/kg body weight respectively. Physiological responses observed were weight gain and expression of Igf-1 with its receptor. Body weight of rat was weighed once per week. Expression of Igf-1 and igf-1R observed with fluorescence immunohistochemistry. The intensity of Igf-1 and Igf-1R expression was analysis using FSX-BSW software. Results: The lowest weight gain was obtained on obese rat model treated with RPE 30 mg/kg body weight. The expression of Igf-1 and Igf-1R were reduced on obese rat model treated with RPE compared with obese rat model of non treatment (P<0.05. The low expression of Igf-1 and Igf-1R was found on obese rat model treated with ellagic acid and RPE 30 mg/kg body weight. Conclusions: The RPE was effecting to the physiological response on obese rat model. The RPE 30 mg/kg body weight inhibited body weight gain and decreased the expression of Igf-1 and Igf- 1R of obese rat model.

Correlation between the in vivo metabolism of hexobarbital and antipyrine in rats

NARCIS (Netherlands)

van der Graaff, M; Vermeulen, N P; Joeres, R P; Vlietstra, T; Breimer, D D

1983-01-01

Two model substrates for oxidative hepatic enzyme activity, viz. hexobarbital (HB) and antipyrine (AP), were given simultaneously to rats by the oral route of administration. Blood concentrations of HB and AP were measured simultaneously by a gas chromatographic method and the urinary excretion of

Carboxyl-modified single-wall carbon nanotubes improve bone tissue formation in vitro and repair in an in vivo rat model

Directory of Open Access Journals (Sweden)

Barrientos-Durán A

2014-09-01

combination of demineralized bone matrix or cartilage particles with SWCNTs were implanted into nude rats, and ectopic bone formation was analyzed. Histological analysis of both types of implants showed high permeability and pore connectivity of the carbon nanotube-soaked implants. Numerous vascularization channels appeared in the formed tissue, additional progenitor cells were recruited, and areas of de novo ossification were found 4 weeks post-implantation. Induction of the expression of bone-related genes and the presence of secreted osteopontin protein were also confirmed by quantitative polymerase chain reaction analysis and immunofluorescence, respectively. In summary, these results are in line with prior contributions that highlight the suitability of SWCNTs as scaffolds with high bone-inducing capabilities both in vitro and in vivo, confirming them as alternatives to current bone-repair therapies. Keywords: human allografts, demineralized bone matrix, cartilage particles, bone regeneration

Evaluating In Vitro-In Vivo Extrapolation of Toxicokinetics.

Science.gov (United States)

Wambaugh, John F; Hughes, Michael F; Ring, Caroline L; MacMillan, Denise K; Ford, Jermaine; Fennell, Timothy R; Black, Sherry R; Snyder, Rodney W; Sipes, Nisha S; Wetmore, Barbara A; Westerhout, Joost; Setzer, R Woodrow; Pearce, Robert G; Simmons, Jane Ellen; Thomas, Russell S

2018-05-01

Prioritizing the risk posed by thousands of chemicals potentially present in the environment requires exposure, toxicity, and toxicokinetic (TK) data, which are often unavailable. Relatively high throughput, in vitro TK (HTTK) assays and in vitro-to-in vivo extrapolation (IVIVE) methods have been developed to predict TK, but most of the in vivo TK data available to benchmark these methods are from pharmaceuticals. Here we report on new, in vivo rat TK experiments for 26 non-pharmaceutical chemicals with environmental relevance. Both intravenous and oral dosing were used to calculate bioavailability. These chemicals, and an additional 19 chemicals (including some pharmaceuticals) from previously published in vivo rat studies, were systematically analyzed to estimate in vivo TK parameters (e.g., volume of distribution [Vd], elimination rate). For each of the chemicals, rat-specific HTTK data were available and key TK predictions were examined: oral bioavailability, clearance, Vd, and uncertainty. For the non-pharmaceutical chemicals, predictions for bioavailability were not effective. While no pharmaceutical was absorbed at less than 10%, the fraction bioavailable for non-pharmaceutical chemicals was as low as 0.3%. Total clearance was generally more under-estimated for nonpharmaceuticals and Vd methods calibrated to pharmaceuticals may not be appropriate for other chemicals. However, the steady-state, peak, and time-integrated plasma concentrations of nonpharmaceuticals were predicted with reasonable accuracy. The plasma concentration predictions improved when experimental measurements of bioavailability were incorporated. In summary, HTTK and IVIVE methods are adequately robust to be applied to high throughput in vitro toxicity screening data of environmentally relevant chemicals for prioritizing based on human health risks.

Autofluorescence dynamics during reperfusion following long-term renal ischemia in a rat model

Energy Technology Data Exchange (ETDEWEB)

Raman, R N; Pivetti, C D; Matthews, D L; Troppmann, C; Demos, S G

2008-02-08

Optical properties of near-surface kidney tissue were monitored in order to assess response during reperfusion to long (20 minutes) versus prolonged (150 minutes) ischemia in an in vivo rat model. Specifically, autofluorescence images of the exposed surfaces of both the normal and the ischemic kidneys were acquired during both injury and reperfusion alternately under 355 nm and 266 nm excitations. The temporal profile of the emission of the injured kidney during the reperfusion phase under 355 nm excitation was normalized to that under 266 nm as a means to account for changes in tissue optical properties independent of ischemia as well as changes in the illumination/collection geometrical parameters in future clinical implementation of this technique using a hand-held probe. The scattered excitation light signal was also evaluated as a reference signal and found to be inadequate. Characteristic time constants were extracted using fit to a relaxation model and found to have larger mean values following 150 minutes of injury. The mean values were then compared with the outcome of a chronic survival study where the control kidney had been removed. Rat kidneys exhibiting longer time constants were much more likely to fail. This may lead to a method to assess kidney viability and predict its ability to recover in the initial period following transplantation or resuscitation.

Ex vivo and in vivo evaluation of microemulsion based transdermal delivery of E. coli specific T4 bacteriophage: A rationale approach to treat bacterial infection.

Science.gov (United States)

Rastogi, Vaibhav; Yadav, Pragya; Verma, Anurag; Pandit, Jayanta K

2017-09-30

This study is focused on the development and evaluation of transdermal delivery of E. coli-specific T4 bacteriophages both ex-vivo and in-vivo using microemulsion as delivery carrier in eradicating the infection caused by E. coli. Microemulsions were prepared by mixing selected oil, surfactants and aqueous phase containing bacteriophages. The formulations were subjected to physicochemical characterization, ex-vivo and in-vivo permeation, stability studies, histological and immunofluorescence examination. The colloidal system exhibits a uniform size distribution, of finite size (150-320nm). Transmission electron microscopy revealed the encapsulation of bacteriophage in the aqueous globule. Ex-vivo permeation across skin was successfully achieved as 6×10 6 PFU/mL and 6.7×10 6 PFU/mL of T4 permeated from ME 6% and 10%, respectively. ME 6% was found to be thermodynamically stable and in-vivo permeation resulted in 5.49×10 5 PFU/mL of bacteriophages in the blood of the E. coli challenged rats, while 2.48×10 5 PFU/mL was detected in germ free rats, at the end of the study. Infected rats that were treated with bacteriophage were survived while significant mortality was observed in others. Histological and IL-6 immunofluorescence examination of the tissues revealed the efficacy/safety of the therapy. The microemulsion-based transdermal delivery of bacteriophage could be a promising approach to treat the infections caused by antibiotic-resistant bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel and existing data for a future physiological toxicokinetic model of ethylene and its metabolite ethylene oxide in mouse, rat, and human.

Science.gov (United States)

Filser, Johannes Georg; Artati, Anna; Li, Qiang; Pütz, Christian; Semder, Brigitte; Klein, Dominik; Kessler, Winfried

2015-11-05

The olefin ethylene is a ubiquitously found gas. It originates predominantly from plants, combustion processes and industrial sources. In mammals, inhaled ethylene is metabolized by cytochrome P450-dependent monooxygenases, particularly by cytochrome P450 2E1, to ethylene oxide, an epoxide that directly alkylates proteins and DNA. Ethylene oxide was mutagenic in vitro and in vivo in insects and mammals and carcinogenic in rats and mice. A physiological toxicokinetic model is a most useful tool for estimating the ethylene oxide burden in ethylene-exposed rodents and humans. The only published physiological toxicokinetic model for ethylene and metabolically produced ethylene oxide is discussed. Additionally, existing data required for the development of a future model and for testing its predictive accuracy are reviewed and extended by new gas uptake studies with ethylene and ethylene oxide in B6C3F1 mice and with ethylene in F344 rats. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Acoustic noise improves motor learning in spontaneously hypertensive rats, a rat model of attention deficit hyperactivity disorder.

Science.gov (United States)

Söderlund, Göran B W; Eckernäs, Daniel; Holmblad, Olof; Bergquist, Filip

2015-03-01

The spontaneously hypertensive (SH) rat model of ADHD displays impaired motor learning. We used this characteristic to study if the recently described acoustic noise benefit in learning in children with ADHD is also observed in the SH rat model. SH rats and a Wistar control strain were trained in skilled reach and rotarod running under either ambient noise or in 75 dBA white noise. In other animals the effect of methylphenidate (MPH) on motor learning was assessed with the same paradigms. To determine if acoustic noise influenced spontaneous motor activity, the effect of acoustic noise was also determined in the open field activity paradigm. We confirm impaired motor learning in the SH rat compared to Wistar SCA controls. Acoustic noise restored motor learning in SH rats learning the Montoya reach test and the rotarod test, but had no influence on learning in Wistar rats. Noise had no effect on open field activity in SH rats, but increased corner time in Wistar. MPH completely restored rotarod learning and performance but did not improve skilled reach in the SH rat. It is suggested that the acoustic noise benefit previously reported in children with ADHD is shared by the SH rat model of ADHD, and the effect is in the same range as that of stimulant treatment. Acoustic noise may be useful as a non-pharmacological alternative to stimulant medication in the treatment of ADHD. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Mechanisms of angiogenesis in a Curculigoside A-treated rat model of cerebral ischemia and reperfusion injury

International Nuclear Information System (INIS)

Zhu, Haibo; He, Jie; Ye, Liang; Lin, Fei; Hou, Jian; Zhong, Yan; Jiang, Wanglin

2015-01-01

Curculigoside A has shown protective effects against rat cortical neuron damage in vivo. However, the molecular mechanisms through which Curculigoside A affords this protection are unclear. In the present study, we sought to elucidate the mechanisms of angiogenesis in rat aortic endothelial cells (RAEC), rat aortic smooth muscle cells (RASMC) as well as a rat model of cerebral ischemia and reperfusion injury following treatment with Curculigoside A. We examined the role of Curculigoside A on RAEC and RASMC proliferation, migration, and tube formation in vitro and in a cerebral ischemia and reperfusion injury rat model. We used the recombinant Dickkopf (DKK)-1 protein, a Wnt/β-catenin inhibitor, and the recombinant WIF-1 protein, a Wnt5a antagonist to determine mechanisms. In addition, we measured leakage of the blood–brain barrier (BBB) and tested for angiogenesis associated proteins. Our data suggest that Curculigoside A induces angiogenesis in vitro by increasing proliferation, migration and tube formation in RAEC and RASMC. The increase in Curculigoside A-induced proliferation and tube formation was counteracted by DKK-1 and WIF-1. Curculigoside A increased expression of VEGF, p-VEGFR, p-CREB, Egr-3, VCAM-1, Ang1 and Tie2 while prohibiting BBB leakage in cerebral ischemia and reperfusion injured rats. However, Cyclosporine A, a CREB inhibitor, reduced the expression of p-CREB, Egr-3, VCAM-1, Ang1 and Tie2. These data suggest that Curculigoside A induces cell proliferation and angiogenesis through the Wnt5a/β-catenin and VEGF/CREB/Egr-3/VCAM-1 signaling axis and promotes maturation and stability of new blood vessels via increasing Ang1 and Tie-2 expression. - Highlights: • Curculigoside A induces cell proliferation through Wnt5a/β-catenin pathway. • Curculigoside A induces angiogenesis via VEGF/CREB/Egr-3/VCAM-1 signaling axis. • Curculigoside A promotes blood vessel maturation via Ang1/Tie2 pathway.

Mechanisms of angiogenesis in a Curculigoside A-treated rat model of cerebral ischemia and reperfusion injury

Energy Technology Data Exchange (ETDEWEB)

Zhu, Haibo [School of Public Health and Management, Binzhou Medical University, Yantai (China); Institute of Toxicology, Binzhou Medical University, Yantai (China); He, Jie [State Key Laboratory of Long-acting Targeting Drug Delivery Technologies (Luye Pharma Group Ltd.), Yantai 264003 (China); Ye, Liang [School of Public Health and Management, Binzhou Medical University, Yantai (China); Institute of Toxicology, Binzhou Medical University, Yantai (China); Lin, Fei; Hou, Jian; Zhong, Yan [State Key Laboratory of Long-acting Targeting Drug Delivery Technologies (Luye Pharma Group Ltd.), Yantai 264003 (China); Jiang, Wanglin, E-mail: jwl518@163.com [School of Pharmaceutical Sciences, Institute of Materia Medica, Binzhou Medical University, Yantai (China)

2015-11-01

Curculigoside A has shown protective effects against rat cortical neuron damage in vivo. However, the molecular mechanisms through which Curculigoside A affords this protection are unclear. In the present study, we sought to elucidate the mechanisms of angiogenesis in rat aortic endothelial cells (RAEC), rat aortic smooth muscle cells (RASMC) as well as a rat model of cerebral ischemia and reperfusion injury following treatment with Curculigoside A. We examined the role of Curculigoside A on RAEC and RASMC proliferation, migration, and tube formation in vitro and in a cerebral ischemia and reperfusion injury rat model. We used the recombinant Dickkopf (DKK)-1 protein, a Wnt/β-catenin inhibitor, and the recombinant WIF-1 protein, a Wnt5a antagonist to determine mechanisms. In addition, we measured leakage of the blood–brain barrier (BBB) and tested for angiogenesis associated proteins. Our data suggest that Curculigoside A induces angiogenesis in vitro by increasing proliferation, migration and tube formation in RAEC and RASMC. The increase in Curculigoside A-induced proliferation and tube formation was counteracted by DKK-1 and WIF-1. Curculigoside A increased expression of VEGF, p-VEGFR, p-CREB, Egr-3, VCAM-1, Ang1 and Tie2 while prohibiting BBB leakage in cerebral ischemia and reperfusion injured rats. However, Cyclosporine A, a CREB inhibitor, reduced the expression of p-CREB, Egr-3, VCAM-1, Ang1 and Tie2. These data suggest that Curculigoside A induces cell proliferation and angiogenesis through the Wnt5a/β-catenin and VEGF/CREB/Egr-3/VCAM-1 signaling axis and promotes maturation and stability of new blood vessels via increasing Ang1 and Tie-2 expression. - Highlights: • Curculigoside A induces cell proliferation through Wnt5a/β-catenin pathway. • Curculigoside A induces angiogenesis via VEGF/CREB/Egr-3/VCAM-1 signaling axis. • Curculigoside A promotes blood vessel maturation via Ang1/Tie2 pathway.

Rates of in vivo (arterial) and in vitro biocorrosion for pure magnesium.

Science.gov (United States)

Bowen, Patrick K; Drelich, Adam; Drelich, Jaroslaw; Goldman, Jeremy

2015-01-01

The development of magnesium-based materials for bioabsorbable stents relies heavily on corrosion testing by immersion in pseudophysiological solutions, where magnesium degrades faster than it does in vivo. The quantitative difference in corrosion kinetics in vitro and in vivo is largely unknown, but, if determined, would help reduce dependence on animal models. In order to create a quantitative in vitro-in vivo correlation based on an accepted measure of corrosion (penetration rate), commercially pure magnesium wires were corroded in vivo in the abdominal aortas of rats for 5-32 days, and in vitro for up to 14 days using Dulbecco's modified eagle medium. Cross-sectioning, scanning electron microscopy, image analysis, a modified penetration rate tailored to degraded wires, and empirical modeling were used to analyze the corroded specimens. In vitro penetration rates were consistently higher than comparable in vivo rates by a factor of 1.2-1.9× (±0.2×). For a sample <20% corroded, an approximate in vitro-in vivo multiplier of 1.3 ± 0.2× was applied, whereas a multiplier of 1.8 ± 0.2× became appropriate when the magnesium specimen was 25-35% degraded. © 2014 Wiley Periodicals, Inc.

In vivo kinetics of intestinal absorption of riboflavin in rats

International Nuclear Information System (INIS)

Feder, S.; Daniel, H.; Rehner, G.

1991-01-01

To investigate absorption kinetics of riboflavin under in vivo conditions, with blood and lymph circulation intact, the small intestine of anesthetized rats was perfused with [ 14 C]riboflavin in a concentration range between 0.31 and 10.00 mumol/L. Apart from the uptake of riboflavin from the perfusate, passage of the vitamin into the portal (vena portae) and peripheral (vena femoralis) blood was determined. The absorption proved to be a dual process: at low substrate concentrations (less than 2 mumol/L) a saturable component predominated; at higher concentrations simple diffusion was found to be the prevailing uptake mechanism. The apparent transport constant of the saturable component was calculated to be 0.38 mumol/L. [ 14 C]flavin concentrations in the portal and peripheral blood were estimated as a function of the riboflavin concentration of the perfusion media. The dual character of the absorption was reflected by the portal blood flavin levels. Due to the high retaining and equalizing capacity of the liver, the [ 14 C]flavin level of the peripheral blood was relatively low and obeyed saturation kinetics. Constants of elimination, determined by pharmacokinetic calculations, were different for the two blood compartments but independent of the concentration of riboflavin in the perfusion media

In vivo labelling in several rat tissues of 'peripheral type' benzodiazepine binding sites

Energy Technology Data Exchange (ETDEWEB)

Benavides, J.; Guilloux, F.; Rufat, P.; Uzan, A.; Renault, C.; Dubroeucq, M.C.; Gueremy, C.; Le Fur, G. (Pharmuka Laboratoires, 92 - Gennevilliers (France))

1984-03-16

'Peripheral type' benzodiazepine binding sites in several rat tissues were labelled by intravenous injection of (/sup 3/H)PK 11195 and (/sup 3/H)RO5-4864. Binding was saturable in all tissues studied and regional distribution paralleled the in vitro binding. A similar potency order of displacing compounds was found in vivo and in vitro PK 11195 > PK 11211 > RO5-4864 > diazepam > dipyridamole > clonazepam. These results demonstrate the feasibility of using this technique to examine the effects of pharmacological manipulation on the binding sites in their native state. However, some properties (broader maximum during time course, higher percentage of particulate binding in the brain and independence of temperature) make (/sup 3/H)PK 11195 the most suitable ligand for this kind of studies.

In vivo evaluation of anticonvulsant and antioxidant effects of phenobarbital microemulsion for transdermal administration in pilocarpine seizure rat model.

Science.gov (United States)

Figueiredo, Kayo Alves; Medeiros, Shirlene Cesário; Neves, Jamilly Kelly Oliveira; da Silva, José Alexsandro; da Rocha Tomé, Adriana; Carvalho, André Luis Menezes; de Freitas, Rivelilson Mendes

2015-04-01

This study aimed to evaluate a microemulsion system (ME) containing phenobarbital in epilepsy model induced by pilocarpine in rats and to oxidative stress and histologic lesions in hippocampus. The microemulsion was applied to the shaved back of Wistar rats. The animals were divided into the following groups: control group (P400); ME50 40mg/kg, topically-t.p.; ME100, 40mg/kg, t.p.; EM50, 40mg/kg, t.p.; phenobarbital solution 40mg/kg (PS), oral. After 60min, behavioral changes were evaluated for 1h in the model of epileptical crisis induced by pilocarpine. Phenobarbital in microemulsion was able to increase the latency for status epilepticus (SE) (p<0.05), decrease the number of epileptical crisis (ME50: p<0.001; ME100: p<0.01) and decrease mortality rate by 80% compared to P400. In EM50 and PS groups, deaths were decreased by 53.3% and 100% respectively. The ME50 and ME100 groups were able to reduce oxidative stress in experimental animals when compared to the P400. The microemulsion was still capable of reducing neuronal damage in the hippocampal areas. The results of this study come in an innovative way, demonstrating the ability of transdermal ME50 and ME100 to reduce pilocarpine-induced epileptical crisis, oxidative stress, besides neuronal damages. Copyright © 2015 Elsevier Inc. All rights reserved.

Simultaneous measurement of glucose blood–brain transport constants and metabolic rate in rat brain using in-vivo 1H MRS

Science.gov (United States)

Du, Fei; Zhang, Yi; Zhu, Xiao-Hong; Chen, Wei

2012-01-01

Cerebral glucose consumption and glucose transport across the blood–brain barrier are crucial to brain function since glucose is the major energy fuel for supporting intense electrophysiological activity associated with neuronal firing and signaling. Therefore, the development of noninvasive methods to measure the cerebral metabolic rate of glucose (CMRglc) and glucose transport constants (KT: half-saturation constant; Tmax: maximum transport rate) are of importance for understanding glucose transport mechanism and neuroenergetics under various physiological and pathological conditions. In this study, a novel approach able to simultaneously measure CMRglc, KT, and Tmax via monitoring the dynamic glucose concentration changes in the brain tissue using in-vivo 1H magnetic resonance spectroscopy (MRS) and in plasma after a brief glucose infusion was proposed and tested using an animal model. The values of CMRglc, Tmax, and KT were determined to be 0.44±0.17 μmol/g per minute, 1.35±0.47 μmol/g per minute, and 13.4±6.8 mmol/L in the rat brain anesthetized with 2% isoflurane. The Monte-Carlo simulations suggest that the measurements of CMRglc and Tmax are more reliable than that of KT. The overall results indicate that the new approach is robust and reliable for in-vivo measurements of both brain glucose metabolic rate and transport constants, and has potential for human application. PMID:22714049

Development of acute hydrocephalus does not change brain tissue mechanical properties in adult rats, but in juvenile rats.

Science.gov (United States)

Pong, Alice C; Jugé, Lauriane; Bilston, Lynne E; Cheng, Shaokoon

2017-01-01

Regional changes in brain stiffness were previously demonstrated in an experimental obstructive hydrocephalus juvenile rat model. The open cranial sutures in the juvenile rats have influenced brain compression and mechanical properties during hydrocephalus development and the extent by which closed cranial sutures in adult hydrocephalic rat models affect brain stiffness in-vivo remains unclear. The aims of this study were to determine changes in brain tissue mechanical properties and brain structure size during hydrocephalus development in adult rat with fixed cranial volume and how these changes were related to brain tissue deformation. Hydrocephalus was induced in 9 female ten weeks old Sprague-Dawley rats by injecting 60 μL of a kaolin suspension (25%) into the cisterna magna under anaesthesia. 6 sham-injected age-matched female SD rats were used as controls. MR imaging (9.4T, Bruker) was performed 1 day before and then at 3 days post injection. T2-weighted anatomical MR images were collected to quantify ventricle and brain tissue cross-sectional areas. MR elastography (800 Hz) was used to measure the brain stiffness (G*, shear modulus). Brain tissue in the adult hydrocephalic rats was more compressed than the juvenile hydrocephalic rats because the skulls of the adult hydrocephalic rats were unable to expand like the juvenile rats. In the adult hydrocephalic rats, the cortical gray matter thickness and the caudate-putamen cross-sectional area decreased (Spearman, P hydrocephalus is complex and is not solely dependent on brain tissue deformation. Further studies on the interactions between brain tissue stiffness, deformation, tissue oedema and neural damage are necessary before MRE can be used as a tool to track changes in brain biomechanics in hydrocephalus.

In vivo cell tracking imaging of hexadecyl-4-[{sup 123,} {sup 124}I]iodobenzoate labeled adipose derived stem cells (ADSCs) in rat heart

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Hwan; Lee, Yong Jin; Lee, Kyo Chul [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

2011-10-15

Monitoring of transplanted stem cells for cardiac repair is important part in regenerative medicine. Direct cell labeling techniques using [{sup 18}F]FDG, [{sup 64}Cu]PTSM and [{sup 99m}Tc]-HMPAO have been developed for in vivo imaging. Especially, {sup 18}F-labeled derivates have been widely used for direct labeling agent. But the {sup 18}F has short half life (T{sub 1/2}={approx}2 h), thus this imaging agent has limitation of in vivo imaging. We used {sup 123}I or {sup 124}I which has relative long half life, to track the transplanted stem cells for a long-term imaging. This study is aimed to track the transplanted adipose derived stem cells (ADSCs) in rat heart using hexadecyl-4-[{sup 123,} {sup 124}I]iodobenzoate ([{sup 123,} {sup 124}I]HIB) mediated direct labeling method in vivo

Kinetic analysis of transport and opioid receptor binding of [3H](-)-cyclofoxy in rat brain in vivo: Implications for human studies

International Nuclear Information System (INIS)

Sawada, Y.; Kawai, R.; McManaway, M.; Otsuki, H.; Rice, K.C.; Patlak, C.S.; Blasberg, R.G.

1991-01-01

[3H]Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model and a classical compartmental pharmacokinetic model were compared. The models included different assumptions for transport across the blood-brain barrier (BBB); estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium constant varied modestly in different brain structures (Keq = 3-9), whereas the binding potential (BP) varied over a much broader range (BP = 0.6-32). In vivo estimates of the opioid receptor dissociation constant were similar for different brain structures (KD = 2.1-5.2 nM), whereas the apparent receptor density (Bmax) varied between 1 (cerebellum) and 78 (thalamus) pmol/g of brain. The receptor dissociation rate constants in cerebrum (k4 = 0.08-0.16 min-1; koff = 0.16-0.23 min-1) and brain vascular permeability (PS = 1.3-3.4 ml/min/g) are sufficiently high to achieve equilibrium conditions within a reasonable period of time. Graphical analysis of the data is inappropriate due to the high tissue-loss rate constant for CF in brain. From these findings, CF should be a very useful opioid receptor ligand for the estimation of the receptor binding parameters in human subjects using [18F]CF and positron emission tomography

Limited Nesting Stress Alters Maternal Behavior and In Vivo Intestinal Permeability in Male Wistar Pup Rats.

Directory of Open Access Journals (Sweden)

Nabila Moussaoui

Full Text Available A few studies indicate that limited nesting stress (LNS alters maternal behavior and the hypothalamic pituitary adrenal (HPA axis of dams and offspring in male Sprague Dawley rats. In the present study, we evaluated the impact of LNS on maternal behavior in Wistar rats, and on the HPA axis, glycemia and in vivo intestinal permeability of male and female offspring. Intestinal permeability is known to be elevated during the first week postnatally and influenced by glucocorticoids. Dams and neonatal litters were subjected to LNS or normal nesting conditions (control from days 2 to 10 postnatally. At day 10, blood was collected from pups for determination of glucose and plasma corticosterone by enzyme immunoassay and in vivo intestinal permeability by oral gavage of fluorescein isothiocyanate-dextran 4kDa. Dams exposed to LNS compared to control showed an increase in the percentage of time spent building a nest (118%, self-grooming (69%, and putting the pups back to the nest (167%. LNS male and female pups exhibited a reduction of body weight by 5% and 4%, adrenal weights/100g body weight by 17% and 18%, corticosterone plasma levels by 64% and 62% and blood glucose by 11% and 12% respectively compared to same sex control pups. In male LNS pups, intestinal permeability was increased by 2.7-fold while no change was observed in females compared to same sex control. There was no sex difference in any of the parameters in control pups except the body weight. These data indicate that Wistar dams subjected to LNS during the first postnatal week have an altered repertoire of maternal behaviors which affects the development of the HPA axis in both sexes and intestinal barrier function in male offspring.

Combined in vivo and ex vivo analysis of mesh mechanics in a porcine hernia model.

Science.gov (United States)

Kahan, Lindsey G; Lake, Spencer P; McAllister, Jared M; Tan, Wen Hui; Yu, Jennifer; Thompson, Dominic; Brunt, L Michael; Blatnik, Jeffrey A

2018-02-01

Hernia meshes exhibit variability in mechanical properties, and their mechanical match to tissue has not been comprehensively studied. We used an innovative imaging model of in vivo strain tracking and ex vivo mechanical analysis to assess effects of mesh properties on repaired abdominal walls in a porcine model. We hypothesized that meshes with dissimilar mechanical properties compared to native tissue would alter abdominal wall mechanics more than better-matched meshes. Seven mini-pigs underwent ventral hernia creation and subsequent open repair with one of two heavyweight polypropylene meshes. Following mesh implantation with attached radio-opaque beads, fluoroscopic images were taken at insufflation pressures from 5 to 30 mmHg on postoperative days 0, 7, and 28. At 28 days, animals were euthanized and ex vivo mechanical testing performed on full-thickness samples across repaired abdominal walls. Testing was conducted on 13 mini-pig controls, and on meshes separately. Stiffness and anisotropy (the ratio of stiffness in the transverse versus craniocaudal directions) were assessed. 3D reconstructions of repaired abdominal walls showed stretch patterns. As pressure increased, both meshes expanded, with no differences between groups. Over time, meshes contracted 17.65% (Mesh A) and 0.12% (Mesh B; p = 0.06). Mesh mechanics showed that Mesh A deviated from anisotropic native tissue more than Mesh B. Compared to native tissue, Mesh A was stiffer both transversely and craniocaudally. Explanted repaired abdominal walls of both treatment groups were stiffer than native tissue. Repaired tissue became less anisotropic over time, as mesh properties prevailed over native abdominal wall properties. This technique assessed 3D stretch at the mesh level in vivo in a porcine model. While the abdominal wall expanded, mesh-ingrown areas contracted, potentially indicating stresses at mesh edges. Ex vivo mechanics demonstrate that repaired tissue adopts mesh properties, suggesting

Pulsed electromagnetic field therapy improves tendon-to-bone healing in a rat rotator cuff repair model.

Science.gov (United States)

Tucker, Jennica J; Cirone, James M; Morris, Tyler R; Nuss, Courtney A; Huegel, Julianne; Waldorff, Erik I; Zhang, Nianli; Ryaby, James T; Soslowsky, Louis J

2017-04-01

Rotator cuff tears are common musculoskeletal injuries often requiring surgical intervention with high failure rates. Currently, pulsed electromagnetic fields (PEMFs) are used for treatment of long-bone fracture and lumbar and cervical spine fusion surgery. Clinical studies examining the effects of PEMF on soft tissue healing show promising results. Therefore, we investigated the role of PEMF on rotator cuff healing using a rat rotator cuff repair model. We hypothesized that PEMF exposure following rotator cuff repair would improve tendon mechanical properties, tissue morphology, and alter in vivo joint function. Seventy adult male Sprague-Dawley rats were assigned to three groups: bilateral repair with PEMF (n = 30), bilateral repair followed by cage activity (n = 30), and uninjured control with cage activity (n = 10). Rats in the surgical groups were sacrificed at 4, 8, and 16 weeks. Control group was sacrificed at 8 weeks. Passive joint mechanics and gait analysis were assessed over time. Biomechanical analysis and μCT was performed on left shoulders; histological analysis on right shoulders. Results indicate no differences in passive joint mechanics and ambulation. At 4 weeks the PEMF group had decreased cross-sectional area and increased modulus and maximum stress. At 8 weeks the PEMF group had increased modulus and more rounded cells in the midsubstance. At 16 weeks the PEMF group had improved bone quality. Therefore, results indicate that PEMF improves early tendon healing and does not alter joint function in a rat rotator cuff repair model. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:902-909, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Effect of antihypertensive agents - captopril and nifedipine - on the functional properties of rat heart mitochondria