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Sample records for bombesin

  1. Characterization of bombesin receptors in peripheral contractile organs.

    OpenAIRE

    Rouissi, N.; Rhaleb, N. E.; Nantel, F; Dion, S.; Drapeau, G; Regoli, D.

    1991-01-01

    1 Guinea-pig and rat urinary bladders, rat stomach and the guinea-pig gall bladder, four isolated organs that show high sensitivity to bombesin, were used to characterize bombesin receptors in peripheral organs. 2 The order of potency of agonists was determined with several naturally occurring peptides of the bombesin series, namely bombesin (BBS), litorin (Lit), neuromedin B (NMB), the gastrin-releasing peptide (GRP 18-27), neuromedin C (NMC) and with some bombesin fragments. It was found th...

  2. Cloning of a receptor for amphibian [Phe13]bombesin distinct from the receptor for gastrin-releasing peptide: identification of a fourth bombesin receptor subtype (BB4).

    OpenAIRE

    Nagalla, S.R.; Barry, B J; Creswick, K C; Eden, P.; Taylor, J. T.; SPINDEL, E.R.

    1995-01-01

    Bombesin is a tetradecapeptide originally isolated from frog skin and demonstrated to have a wide range of actions in mammals. Based on structural homology and similar biological activities, gastrin-releasing peptide (GRP) has been considered the mammalian equivalent of bombesin. We previously reported that frogs have both GRP and bombesin, which therefore are distinct peptides. We now report the cloning of a bombesin receptor subtype (BB4) that has higher affinity for bombesin than GRP. PCR ...

  3. Bombesin facilitates GABAergic transmission and depresses epileptiform activity in the entorhinal cortex.

    Science.gov (United States)

    Zhang, Hao-peng; Xiao, Zhaoyang; Cilz, Nicholas I; Hu, Binqi; Dong, Hailong; Lei, Saobo

    2014-01-01

    Bombesin and the bombesin-like peptides including neuromedin B (NMB) and gastrin-releasing peptide (GRP) are important neuromodulators in the brain. We studied their effects on GABAergic transmission and epileptiform activity in the entorhinal cortex (EC). Bath application of bombesin concentration-dependently increased both the frequency and amplitude of sIPSCs recorded from the principal neurons in the EC. Application of NMB and GRP exerted the same effects as bombesin. Bombesin had no effects on mIPSCs recorded in the presence of TTX but slightly depressed the evoked IPSCs. Omission of extracellular Ca(2+) or inclusion of voltage-gated Ca(2+) channel blockers, Cd(2+) and Ni(2+), blocked bombesin-induced increases in sIPSCs suggesting that bombesin increases GABA release via facilitating extracellular Ca(2+) influx. Bombesin induced membrane depolarization and slightly increased the input resistance of GABAergic interneurons recorded from layer III of the EC. The action potential firing frequency of the interneurons was also increased by bombesin. Bombesin-mediated depolarization of interneurons was unlikely to be mediated by the opening of a cationic conductance but due to the inhibition of inward rectifier K(+) channels. Bath application of bombesin, NMB and GRP depressed the frequency of the epileptiform activity elicited by deprivation of Mg(2+) from the extracellular solution suggesting that bombesin and the bombesin-like peptides have antiepileptic effects in the brain. PMID:23966303

  4. High-affinity receptors for bombesin-like peptides in normal guinea pig lung membranes

    Energy Technology Data Exchange (ETDEWEB)

    Lach, E.; Trifilieff, A.; Landry, Y.; Gies, J.P. (Univ. Louis Pasteur, Illkirch (France))

    1991-01-01

    The binding of the radiolabeled bombesin analogue ({sup 125}I-Tyr{sup 4})bombesin to guinea-pig lung membranes was investigated. Binding of ({sup 125}I-Tyr{sup 4})bombesin was specific, saturable, reversible and linearly related to the protein concentration. Scatchard analysis of equilibrium binding data at 25C indicated the presence of a single class of non-interacting binding sites for bombesin (B{sub max} = 7.7 fmol/mg protein). The value of the equilibrium dissociation constant (K{sub D} = 90 pM) agrees with a high-affinity binding site. Bombesin and structurally related peptides such as ({sup 125}I-Tyr{sup 4})bombesin, neuromedin B and neuromedin C inhibited the binding of ({sup 125}I-Tyr{sup 4})bombesin in an order of potencies as follows: ({sup 125}I-Tyr{sup 4})bombesin {gt} bombesin {ge} neuromedin C {much gt} neuromedin B. These results indicate that guinea-pig lung membranes possess a single class of bombesin receptors with a high affinity for bombesin and a lower one for neuromedin B.

  5. Neuromedin B receptor in esophagus: evidence for subtypes of bombesin receptors

    Energy Technology Data Exchange (ETDEWEB)

    Von Schrenck, T.; Heinz-Erian, P.; Moran, T.; Mantey, S.A.; Gardner, J.D.; Jensen, R.T.

    1989-04-01

    To identify receptors for bombesin-related peptides in the rat esophagus, we measured binding of 125I-Bolton-Hunter neuromedin B (125I-BH-neuromedin B) and 125I-(Tyr4)bombesin to tissue sections from the rat esophagus and compared the results with those for rat pancreas. Esophagus bound both tracers, whereas pancreas bound only 125I-(Tyr4)bombesin. In each tissue binding was saturable, dependent on pH, on time, and on temperature, reversible, and specific. Autoradiography demonstrated binding of both tracers only to the muscularis mucosae of the esophagus and binding of 125I-(Tyr4)bombesin diffusely over pancreatic acini. In the esophagus, the relative potencies for inhibition of binding of both tracers were as follows: neuromedin B greater than bombesin greater than GRP = neuromedin C; similar relative potencies were found for causing contraction of muscle strips from whole esophagus and from the isolated muscularis mucosae. In pancreas tissue sections and dispersed acini, the relative potencies for inhibition of binding of 125I-(Tyr4)bombesin were as follows: bombesin greater than GRP = neuromedin C much greater than neuromedin B. Similar relative potencies were found for stimulation of enzyme secretion from dispersed pancreatic acini. Computer analysis in both tissues demonstrated only a single binding site. The present study demonstrates that rat esophagus muscle possesses specific receptors for bombesin-related peptides. Furthermore, this study shows that the esophageal bombesin receptors represent a previously unidentified class of bombesin receptors in that they have a higher affinity for neuromedin B than for bombesin. In contrast, the pancreatic bombesin receptors have, like all other bombesin receptors described to date, a high affinity for bombesin, but low affinity for neuromedin B.

  6. Bombesin-Like Receptor 3: Physiology of a Functional Orphan.

    Science.gov (United States)

    Xiao, Cuiying; Reitman, Marc L

    2016-09-01

    Bombesin-like receptor 3 (BRS-3) is an X-linked orphan Gq-coupled receptor that regulates food intake, metabolic rate, body temperature, heart rate, blood pressure, and insulin secretion. Most BRS-3 actions occur via the brain, through mechanisms including regulating sympathetic outflow. Ablation of Brs3 causes obesity, while synthetic agonists produce weight loss. PMID:27055378

  7. The study of bombesin-like neuropeptides from mammals

    OpenAIRE

    Mukai, Hidehito

    1990-01-01

    About 20 years has elapsed since the discovery of bombesin by Erspamer and his coworkers.In this period,more than 10 peptides were isolated and characterized.These included gastrinreleasing peptide(GRP),neuromedin B(NMB)and their fragment ...

  8. Bombesin-like immunoreactivity in the nervous system of hydra

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J; Dockray, G J; Yanaihara, N

    1981-01-01

    With immunocytochemical methods, nerve cells have been detected in Hydra attenuata containing bombesin-like immunoreactivity. These nerve cells are located in ectoderm of all body regions of the animal and are especially abundant in basal disk and tentacles. Radioimmunoassay of extracts of hydra ...

  9. Mechanism of bombesin-induced tonic contraction of the porcine lower esophageal sphincter.

    Science.gov (United States)

    Tsai, Ching-Chung; Chang, Li-Ching; Lin, Kai-Jen; Tey, Shu-Leei; Su, Yu-Tsun; Liu, Ching-Wen; Tsai, Tong-Rong; Huang, Shih-Che

    2015-01-01

    Gastroesophageal reflux disease (GERD) is a disorder that is related to an incompetent lower esophageal sphincter (LES). Previous studies showed that bombesin could increase LES pressure in humans and opossums. The aim of the present study was to characterize the effects of bombesin on porcine LES contraction. We used the selective agonists, neuromedin B (NMB), gastrin-releasing peptide (GRP), and [D-Tyr(6),Apa-4Cl(11),Phe(13),Nle(14)]bombesin-(6-14) (DTACPN-BN), as well as receptor antagonists of bombesin receptor subtype 2 (BB2), and 3 (BB3) for ex vivo contraction studies. Atropine, nifedipine, tetrodotoxin, and ω-conotoxin GVIA were used to explore the agonist-induced LES contraction mechanism. Reverse transcription polymerase chain reaction and immunohistochemistry were applied to detect bombesin receptor expression. Our results indicate that GRP and DTACPN-BN, but not NMB, induced tonic contractions of the porcine LES in a dose-dependent manner, and the contractions were inhibited with selective BB2 and BB3 antagonists. The GRP-induced contraction is mainly caused by L-type Ca(2+) channel-mediated Ca(2+) influx. However, DTACPN-BN-induced contractions are associated with neuronal conduction. RT-PCR and immunohistochemistry revealed that BB2 and BB3 were expressed in the porcine LES. Bombesin-induced tonic contraction of the LES is mediated through BB2 and BB3. Bombesin, BB2, and BB3 agonists might have the potential to treat GERD. PMID:26522854

  10. Molecular cloning of the bombesin/gastrin-releasing peptide receptor from Swiss 3T3 cells.

    OpenAIRE

    Battey, J F; Way, J M; Corjay, M H; Shapira, H; Kusano, K; Harkins, R.; Wu, J M; Slattery, T; Mann, E.; Feldman, R I

    1991-01-01

    The mammalian bombesin-like peptides gastrin-releasing peptide (GRP) and neuromedin B regulate numerous and varied cell physiologic processes in various cell types and have also been implicated as autocrine growth factors influencing the pathogenesis and progression of human small cell lung carcinomas. We report here the molecular characterization of the bombesin/GRP receptor. Structural analysis of cDNA clones isolated from Swiss 3T3 murine embryonal fibroblasts shows that the GRP receptor i...

  11. Bombesin family receptor and ligand gene expression in human colorectal cancer and normal mucosa

    OpenAIRE

    Chave, H S; Gough, A C; Palmer, K.; Preston, S. R.; Primrose, J N

    1999-01-01

    Bombesin-like peptides and their receptors are widely distributed throughout the gut and are potential mitogens for a number of gastrointestinal (GI) cancers. We have analysed the expression of bombesin-like peptides and their receptor subtypes in normal and neoplastic colorectal tissue. Expression was analysed by reverse transcription polymerase chain reaction (RT-PCR) using receptor and ligand subtype-specific primers and then expression localized by in situ hybridization (ISH) with ribopro...

  12. Peripheral injection of bombesin induces c-Fos in NUCB2/nesfatin-1 neurons.

    Science.gov (United States)

    Engster, Kim-Marie; Kroczek, Arthur L; Rose, Matthias; Stengel, Andreas; Kobelt, Peter

    2016-10-01

    As anorexigenic hormones bombesin and nucleobindin2 (NUCB2)/nesfatin-1 decrease food intake in rodents. Both hormones have been described in brain nuclei that play a role in the modulation of hunger and satiety, like the paraventricular nucleus of the hypothalamus (PVN) and the nucleus of the solitary tract (NTS). However, the direct interaction of the two hormones is unknown so far. The aim of study was to elucidate whether bombesin directly interacts with NUCB2/nesfatin-1 neurons in the PVN and NTS. Therefore, we injected bombesin intraperitoneally (ip) at two doses (26 and 32nmol/kg body weight) and assessed c-Fos activation in the PVN, arcuate nucleus (ARC) and NTS compared to vehicle treated rats (0.15M NaCl). We also performed co-localization studies with oxytocin or tyrosine hydroxylase. Bombesin at both doses increased the number of c-Fos positive neurons in the PVN (pNTS (p0.05). In the PVN and NTS the number of c-Fos positive neurons colocalized with NUCB2/nesfatin-1 increased after bombesin injection compared to vehicle treatment (pNTS (pNTS giving rise to a possible interaction between bombesin and NUCB2/nesfatin-1 in the modulation of food intake. PMID:27396908

  13. Peripheral injection of bombesin induces c-Fos in NUCB2/nesfatin-1 neurons.

    Science.gov (United States)

    Engster, Kim-Marie; Kroczek, Arthur L; Rose, Matthias; Stengel, Andreas; Kobelt, Peter

    2016-10-01

    As anorexigenic hormones bombesin and nucleobindin2 (NUCB2)/nesfatin-1 decrease food intake in rodents. Both hormones have been described in brain nuclei that play a role in the modulation of hunger and satiety, like the paraventricular nucleus of the hypothalamus (PVN) and the nucleus of the solitary tract (NTS). However, the direct interaction of the two hormones is unknown so far. The aim of study was to elucidate whether bombesin directly interacts with NUCB2/nesfatin-1 neurons in the PVN and NTS. Therefore, we injected bombesin intraperitoneally (ip) at two doses (26 and 32nmol/kg body weight) and assessed c-Fos activation in the PVN, arcuate nucleus (ARC) and NTS compared to vehicle treated rats (0.15M NaCl). We also performed co-localization studies with oxytocin or tyrosine hydroxylase. Bombesin at both doses increased the number of c-Fos positive neurons in the PVN (pNTS (p0.05). In the PVN and NTS the number of c-Fos positive neurons colocalized with NUCB2/nesfatin-1 increased after bombesin injection compared to vehicle treatment (pNTS (pNTS giving rise to a possible interaction between bombesin and NUCB2/nesfatin-1 in the modulation of food intake.

  14. Click chemistry for [{sup 99m}Tc(CO){sub 3}] labeling of Lys{sup 3}-bombesin

    Energy Technology Data Exchange (ETDEWEB)

    Ferro-Flores, G., E-mail: ferro_flores@yahoo.com.m [Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, Estado de Mexico, C.P. 52750 (Mexico); Rivero, I.A. [Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, Estado de Mexico, C.P. 52750 (Mexico); Instituto Tecnologico de Tijuana, Baja California (Mexico); Santos-Cuevas, C.L. [Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, Estado de Mexico, C.P. 52750 (Mexico); Universidad Autonoma del Estado de Mexico (Mexico); Sarmiento, J.I. [Instituto Tecnologico de Tijuana, Baja California (Mexico); Arteaga de Murphy, C. [Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran (Mexico); Ocampo-Garcia, B.E. [Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, Estado de Mexico, C.P. 52750 (Mexico); Garcia-Becerra, R.; Ordaz-Rosado, D. [Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran (Mexico)

    2010-12-15

    {sup 99m}Tc-HYNIC labeled Lys{sup 3}-bombesin has shown specific binding to gastrin-releasing peptide receptors (GRP-r) over-expressed in cancer cells. Click chemistry offers an innovative functionalization strategy for biomolecules such as bombesin. The aim of this research was to apply a click chemistry approach for [{sup 99m}Tc(CO){sub 3}] labeling of Lys{sup 3}-bombesin and to compare the in vitro MCF7 breast cancer cell uptake and biodistribution profile in mice with that of {sup 99m}Tc-EDDA/HYNIC-Lys{sup 3}-bombesin. The results suggest a higher lipophilicity for {sup 99m}Tc(CO){sub 3}-triazole-Lys{sup 3}-bombesin which explains its higher in vivo hepatobiliary elimination. Pancreas-to-blood ratio for {sup 99m}Tc(CO){sub 3}-triazole-Lys{sup 3}-bombesin was 4.46 at 3 h and both bombesin radiopharmaceuticals showed specific recognition for GRP receptors in MCF7 cancer cells. Click chemistry is a reliable approach for [{sup 99m}Tc(CO){sub 3}] labeling of Lys{sup 3}-bombesin.

  15. GLP1- and GIP-producing cells rarely overlap and differ by bombesin receptor-2 expression and responsiveness

    DEFF Research Database (Denmark)

    Svendsen, Berit; Pais, Ramona; Engelstoft, Maja S;

    2016-01-01

    secretion of both GLP1 and GIP, whereas bombesin/neuromedin C only stimulated GLP1 secretion. Expression analysis showed high expression of the bombesin 2 receptor in GLP1 positive cells, but no expression in GIP-positive cells. These data indicate both expressional and functional differences between the...

  16. DOTA-PESIN, a DOTA-conjugated bombesin derivative designed for the imaging and targeted radionuclide treatment of bombesin receptor-positive tumours

    International Nuclear Information System (INIS)

    We aimed at designing and developing a novel bombesin analogue, DOTA-PEG4-BN(7-14) (DOTA-PESIN), with the goal of labelling it with 67/68Ga and 177Lu for diagnosis and radionuclide therapy of prostate and other human cancers overexpressing bombesin receptors. The 8-amino acid peptide bombesin (7-14) was coupled to the macrocyclic chelator DOTA via the spacer 15-amino-4,7,10,13-tetraoxapentadecanoic acid (PEG4). The conjugate was complexed with Ga(III) and Lu(III) salts. The GRP receptor affinity and the bombesin receptor subtype profile were determined in human tumour specimens expressing the three bombesin receptor subtypes. Internalisation and efflux studies were performed with the human GRP receptor cell line PC-3. Xenografted nude mice were used for biodistribution. [GaIII/LuIII]-DOTA-PESIN showed good affinity to GRP and neuromedin B receptors but no affinity to BB3. [67Ga/177Lu]-DOTA-PESIN internalised rapidly into PC-3 cells whereas the efflux from PC-3 cells was relatively slow. In vivo experiments showed a high and specific tumour uptake and good retention of [67Ga/177Lu]-DOTA-PESIN. [67Ga/177Lu]-DOTA-PESIN highly accumulated in GRP receptor-expressing mouse pancreas. The uptake specificity was demonstrated by blocking tumour uptake and pancreas uptake. Fast clearance was found from blood and all non-target organs except the kidneys. High tumour-to-normal tissue ratios were achieved, which increased with time. PET imaging with [68Ga]-DOTA-PESIN was successful in visualising the tumour at 1 h post injection. Planar scintigraphic imaging showed that the 177Lu-labelled peptide remained in the tumour even 3 days post injection. The newly designed ligands have high potential with regard to PET and SPECT imaging with 68/67Ga and targeted radionuclide therapy with 177Lu. (orig.)

  17. Lutetium-177 Labeled Bombesin Peptides for Radionuclide Therapy.

    Science.gov (United States)

    Reynolds, Tamila Stott; Bandari, Rajendra P; Jiang, Zongrun; Smith, Charles J

    2016-01-01

    The rare-earth radionuclides that decay by beta particle (β-) emission are considered to be ideal in the context of targeted radiotherapy. The rare-earth isotopes exist primarily in the 3+ oxidation state and are considered to be hard metal centers, requiring multidentate, hard donor ligands such as the poly(aminocarboxylates) for in vivo kinetic inertness. 177Lu is a rare-earth radionuclide that is produced in moderate specific activity (740 GBq/mg) by direct neutron capture of enriched 176Lu via the 176Lu(n,γ)177Lu nuclear reaction. 177Lu has a half-life of 6.71 d, decays by beta emission (Ebmax = 0.497 MeV), and emits two imagable photons (113keV, 3% and 208kev, 11%). High specific activity, no-carrier-added 177Lu can also be prepared by an indirect neutron capture nuclear reaction on a 176Yb target. Herein, we report upon bombesin (BBN) peptides radiolabeled with 177Lu. The impetus driving many of the research studies that we have described in this review is that the high-affinity gastrin releasing peptide receptor (GRPR, BBN receptor subtype 2, BB2) has been identified in tissue biopsy samples and immortalized cell lines of many human cancers and is an ideal biomarker for targeting early-stage disease. Early on, the ability of GRPR agonists to be rapidly internalized coupled with a high incidence of GRPR expression on various neoplasias was a driving force for the design and development of new diagnostic and therapeutic agents targeting GRP receptor-positive tumors. Recent reports, however, show compelling evidence that radiopharmaceutical design and development based upon antagonist-type ligand frameworks clearly bears reexamination. Last of all, the ability to target multiple biomarkers simultaneously via a heterodimeric targeting ligand has also provided a new avenue to investigate the dual targeting capacity of bivalent radioligands for improved in vivo molecular imaging and treatment of specific human cancers. In this report, we describe recent advances

  18. Enhancement of cytotoxicity of antimicrobial peptide magainin Ⅱ in tumor cells by bombesin-targeted delivery

    Institute of Scientific and Technical Information of China (English)

    Shan LIU; Hao YANG; Lin WAN; Hua-wei CAI; Sheng-fu LI; You-ping LI; Jing-qiu CHENG; Xiao-feng LU

    2011-01-01

    Aim: To investigate whether the conjugation of magainin II(MG2),an antimicrobial peptides(AMPs),to the tumor-homing peptide bombesin could enhance its cytotoxicity in tumor cells.Methods: A magainin Ⅱ-bombesin conjugate(MG2B)was constructed by attaching magainin Ⅱ(MG2)to bombesin at its N-terminus.The peptides were synthesized using Fmoc-chemistry.The in vitro cytotoxicity of the peptide in cancer cells was quantitatively determined using the CCK-8 celt counting kit.Moreover,the in vivo antitumor effect of the peptide was determined in tumor xenograft models.Results: The IC50 of MG2B for cancer cells(10-15 μmol/L)was at least 10 times lower than the IC50 of unconjugated MG2(125μmol/L).Moreover,the binding affinity of MG2B for cancer cells was higher than that of unconjugated MG2.In contrast,conjugation to a bombesin analog lacking the receptor-binding domain failed to increase the cytotoxicity of MG2,suggesting that bombesin conjugation enhances the cytotoxicity of MG2 in cancer cells through improved binding.Indeed,MG2B selectively induced cell death in cancer cells in vitro with the IC50 ranging from 10 to 15 μmol/L,which was about 6-10 times lower than the IC50 for normal cells.MG2B(20mg/kg per day,intratumorally injected for 5 d)also exhibited antitumor effects in mice bearing MCF-7 tumor grafts.The mean weights of tumor grafts in MG2B-and PBS-treated mice were 0.21±0.05 g and 0.59±0.12 g,respectively.Conclusion: The results suggest that conjugation of AMPs to bombesin might be an alternative approach for targeted cancer therapy.

  19. Pharmacological characterization of a selective agonist for Bombesin Receptor Subtype - 3

    OpenAIRE

    Zhang, Li; Nothacker, Hans-Peter; Wang, Zhiwei; Bohn, Laura M.; Civelli, Olivier

    2009-01-01

    Bombesin receptor subtype-3 (BRS-3) is an orphan G protein-coupled receptor in the bombesin receptor family that still awaits identification of its natural ligand. BRS-3 deficient mice develop a mild late-onset obesity with metabolic defects, implicating BRS-3 plays a role in feeding and metabolism. We describe here the pharmacological characterization of a synthetic compound, 16a, which serves as a potent agonist for BRS-3. This compound is selective for BRS-3 as it does not activate neurome...

  20. Rhodium-105 Bombesin Analogs for Prostate Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Silvia S. Jurisson, PhD

    2005-12-31

    Over the period of this grant (11/01/2001 to 12/31/2005), the consistent and reproducible production of Rh-105, synthesis and evaluation of three new chelate systems based on hydroxymethyl phosphines, development of a new non-hydroxymethyl phosphine N{sub 2}P{sub 2} chelate system, conjugation of two of the chelates to the bombesin peptide analog BBN[7-14]NH{sub 2}, evaluation of the bombesin conjugates and their Rh-105 complexes for stability, cell binding affinity, and in vivo biodistribution in normal mice has been developed. The BBN analogs bind to GRP receptors that are overexpressed on PC-3 prostate tumor cells. A dedicated glove box is used for the separation and isolation of {sup 105}Rh from the target ({sup 104}Ru). All tubing/connections/valves from the point of the Cl{sub 2} tank are made of Teflon to minimize/eliminate the introduction of any metal into the process (e.g., iron from stainless steel corrosion). The separation of {sup 105}Rh produced from the enriched {sup 104}Ru target involves oxidation of the enriched {sup 104}Ru metal target to ruthenium tetroxide with chlorine gas and sodium hydroxide solution to generate hypochlorite in situ. The RuO4 is removed by distillation and the {sup 105}Rh remaining in the reaction vial is converted into {sup 105}Rh-chloride by acidification with hydrochloric acid and heating. The {sup 105}Rh production process has become reproducible over the past year to consistently make 10-30 mCi of {sup 105}Rh from 1-3 mg of an enriched (99.21%) {sup 104}Ru target. The process itself involves irradiation of the enriched {sup 104}Ru target in the core of the reactor (University of Missouri Research Reactor (MURR)) for one week to yield 16-40 mCi of {sup 105}Rh. The irradiated target is processed to separate the Rh-105 in high specific activity from the {sup 104}Ru target. The irradiated target is dissolved in NaOH (2M, 3 mL) by bubbling Cl{sub 2} gas through the solution (generating NaOCl in situ) to generate RuO{sub 4

  1. Bombesin receptor-mediated imaging and cytotoxicity: review and current status

    OpenAIRE

    Sancho, Veronica; Di Florio, Alessia; Moody, Terry W.; Jensen, Robert T.

    2011-01-01

    The three mammalian bombesin (Bn) receptors (gastrin-releasing peptide [GRP] receptor, neuromedin B [NMB] receptor, BRS-3) are one of the classes of G protein-coupled receptors that are most frequently over-express/ectopically expressed by common, important malignancies. Because of the clinical success of somatostatin receptor-mediated imaging and cytotoxicity with neuroendocrine...

  2. Validation of the production process of core-equipment HYNIC-Bombesin-Sn

    International Nuclear Information System (INIS)

    The validation process is establishing documented evidence that provides a high degree of assurance that a specific process consistently will produce a product that will meet specifications and quality attributes preset and, therefore, ensures the efficiency and effectiveness of a product. The radiopharmaceutical 99mTc-HYNlC-Bombesin is part of the gastrin-releasing peptide (GRP) analogues of bombesin that are radiolabelled with technetium 99 metastable for molecular images obtention. Is obtained from freeze-dry formulations kits (core- equipment)) and has reported a very high stability in human serum, specific binding to receptors and rapid internalization. Biodistribution data in mice showed rapid blood clearance with predominant renal excretion and specific binding to tissues with positive response to GRP receptors. According to biokinetics studies performed on patients with breast cancer, breast show a marked asymmetry with increased uptake in neoplastic breast in healthy women and the uptake of radiopharmaceuticals is symmetrical in both breasts. No reported adverse reactions. In this paper, the prospective validation core-equipment HYNlC-Bombesin-Sn, which was shown consistently that the product meets the specifications and quality, attributes to preset from the obtained from the diagnostic radiopharmaceutical third generation: 99mTc-HYNlC-Bombesin. The process was successfully validated and thereby ensuring the efficiency and effectiveness of this agent as a preliminary diagnostic for approval to be marketed. (Author)

  3. DOTA-PESIN, a DOTA-conjugated bombesin derivative designed for the imaging and targeted radionuclide treatment of bombesin receptor-positive tumours

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hanwen; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Department of Radiology, Basel (Switzerland); Schuhmacher, Jochen; Eisenhut, Michael [German Cancer Research Centre, Department of Radiopharmaceutical Chemistry, Heidelberg (Germany); Waser, Beatrice; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, P.O. Box 62, Berne (Switzerland); Wild, Damian [University Hospital, Clinic and Institute of Nuclear Medicine, Department of Radiology, Basel (Switzerland)

    2007-08-15

    We aimed at designing and developing a novel bombesin analogue, DOTA-PEG{sub 4}-BN(7-14) (DOTA-PESIN), with the goal of labelling it with {sup 67/68}Ga and {sup 177}Lu for diagnosis and radionuclide therapy of prostate and other human cancers overexpressing bombesin receptors. The 8-amino acid peptide bombesin (7-14) was coupled to the macrocyclic chelator DOTA via the spacer 15-amino-4,7,10,13-tetraoxapentadecanoic acid (PEG{sub 4}). The conjugate was complexed with Ga(III) and Lu(III) salts. The GRP receptor affinity and the bombesin receptor subtype profile were determined in human tumour specimens expressing the three bombesin receptor subtypes. Internalisation and efflux studies were performed with the human GRP receptor cell line PC-3. Xenografted nude mice were used for biodistribution. [Ga{sup III}/Lu{sup III}]-DOTA-PESIN showed good affinity to GRP and neuromedin B receptors but no affinity to BB3. [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN internalised rapidly into PC-3 cells whereas the efflux from PC-3 cells was relatively slow. In vivo experiments showed a high and specific tumour uptake and good retention of [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN. [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN highly accumulated in GRP receptor-expressing mouse pancreas. The uptake specificity was demonstrated by blocking tumour uptake and pancreas uptake. Fast clearance was found from blood and all non-target organs except the kidneys. High tumour-to-normal tissue ratios were achieved, which increased with time. PET imaging with [{sup 68}Ga]-DOTA-PESIN was successful in visualising the tumour at 1 h post injection. Planar scintigraphic imaging showed that the {sup 177}Lu-labelled peptide remained in the tumour even 3 days post injection. The newly designed ligands have high potential with regard to PET and SPECT imaging with {sup 68/67}Ga and targeted radionuclide therapy with {sup 177}Lu. (orig.)

  4. Bombesin stimulation of c-fos and c-myc gene expression in cultured of Swiss 3T3 cells

    International Nuclear Information System (INIS)

    Bombesin has been show to be a potent mitogen for Swiss 3T3 cells. At nanomolar concentrations it stimulates DNA synthesis in quiescent cultures of 3T3 cells and also induces the expression of c-fos and c-myc mRNA. c-fos mRNA transcripts dramatically increase 15 min after the addition of bombesin, are still abundant after 30-60 min and then decrease. c-myc mRNA induction is detectable later, 1 h after bombesin treatment. Conversely, no changes in c-Ki-ras expression are observed after stimulation with bombesin. These results demonstrate that the increased expression of c-fos and c-myc mRNAs appears to be a common response to diverse agents that induce DNA synthesis and cell proliferation

  5. Synthesis and evaluation of a technetium-99m labeled cytotoxic bombesin peptide conjugate for targeting bombesin receptor-expressing tumors

    Energy Technology Data Exchange (ETDEWEB)

    Okarvi, Subhani M. [Cyclotron and Radiopharmaceuticals Department, King Faisal Specialist Hospital and Research Centre, MBC-03, PO Box 3354, Riyadh 11211 (Saudi Arabia)], E-mail: sokarvi@kfshrc.edu.sa; Al Jammaz, Ibrahim [Cyclotron and Radiopharmaceuticals Department, King Faisal Specialist Hospital and Research Centre, MBC-03, PO Box 3354, Riyadh 11211 (Saudi Arabia)

    2010-04-15

    Conjugation of the cytotoxic drugs to receptor-binding peptides is an attractive approach for the targeted delivery of cytotoxic peptide conjugates to tumor cells. In an attempt to develop an efficient peptide-based radiopharmaceutical for targeting bombesin (BN) receptor-expressing tumors (i.e., breast and prostate), we have prepared by solid-phase peptide synthesis, a novel BN analog derived from the universal sequence of BN and conjugated to a widely characterized antineoplastic agent, methotrexate (MTX). MTX-BN, after radiolabeling with {sup 99m}Tc via stannous-tartrate exchange, showed a good stability against cysteine and histidine transchelation as well as a high in vitro metabolic stability in human plasma. In vitro cell-binding and internalization on MDA-MB-231, MCF-7, T47-D breast cancer and PC-3 prostate cancer cell lines demonstrated high affinity and specificity of {sup 99m}Tc-MTX-BN towards both human breast and prostate cancer cells (binding affinities in nanomolar range). In addition, the radioconjugate displayed a significant internalization (values ranged between 19-35%) into the tumor cells. In vivo biodistribution and clearance kinetics in Balb/c mice are characterized by an efficient clearance from the blood and excretion mainly through the renal-urinary pathway with some elimination via the hepatobiliary system. In vivo tumor uptake in nude mice bearing MDA-MB-231 cells was 2.70{+-}0.44% ID/g at 1 h, whereas in nude mice with human epidermoid KB cells the accumulation in the tumor was found to be 1.48{+-}0.31% ID/g at 1 h post injection. The tumor uptake was always higher than in the blood and muscle, with good tumor retention and good tumor-to-blood and tumor-to-muscle ratios. The accumulation/retention in the major organs (i.e., lungs, stomach, liver, intestines, etc.) was low to moderate (<6% ID/g) in both healthy and tumor-bearing mice. However, the uptake/retention in the kidneys was rather high (up to 11.05{+-}1.80% ID/g), which is of a

  6. Synergistic bombesin and insulin stimulation of DNA synthesis in human fetal kidney in serum-free culture.

    Science.gov (United States)

    Brière, N; Chailler, P

    1993-05-01

    The respective influences of growth factors during kidney development can be directly evaluated using the chemically-defined serum-free culture system perfected in our laboratory. Since, in this culture model, conditions are minimal for growth and differentiation, DNA synthesis sharply decreases during the first 48 h. The addition of epidermal growth factor (EGF, 100 ng/ml), insulin (5 micrograms/ml) and transferrin (5 micrograms/ml) significantly restores this important cellular function. The objective of the present study was to determine the influence of bombesin, a potent mitogen, supplemented alone or in combination with insulin, transferrin and/or EGF. Cortical explants of human fetal kidneys (17-20 weeks) were maintained during 5 days in culture. When compared with 5 day controls (L-15 medium only), bombesin generated a maximal though weak effect on DNA synthesis at a concentration of 0.3 nM, corresponding to a stimulation index (SI) of 22%. When combined with either transferrin or EGF, or with transferrin plus EGF, bombesin did not alter the SI of individual factors. Insulin, in turn, greatly increased DNA synthesis (SI = 169%), while bombesin strongly potentiated this effect (SI = 275%). Transferrin also enhanced insulin SI from 169 to 240%. When added as a third factor, bombesin further potentiated the effectiveness (SI = 338%) of the combination insulin plus transferrin. These results indicate that bombesin controls cell proliferation in synergism with other regulators and hence may act as a competence growth factor during nephrogenesis.

  7. The effects of the phyllolitorin analogue [desTrp3,Leu8]phyllolitorin on scratching induced by bombesin and related peptides in rats

    OpenAIRE

    Johnson, Mark D; Ko, Mei-Chuan; Choo, Kevin S.; Traynor, John R.; Mosberg, Henry I.; Naughton, Norah N.; Woods, James H

    1999-01-01

    Bombesin along with several closely related neuropeptides elicit scratching behavior when administered centrally. The first part of the study was designed to determine the antagonistic effects of a novel phyllolitorin analogue wdesTrp3,Leu8]phyllolitorin (DTP) on scratching induced by three peptides (bombesin, neuromedin-C, and [Leu8]phyllolitorin). In addition, the binding affinity of each peptide for the bombesin receptor site was determined. DTP (30 μg) inhibited scratching induced by thes...

  8. Effects of bombesin and neuromedin-B on the proliferative activity of the rat adrenal cortex

    OpenAIRE

    Markowska, A.; Nussdorfer, G G; Malendowicz, L.K.

    1993-01-01

    Bombesin (BM) and neuromedin-B (NMB) exert similar biological effects, acting via two functionally distinct BM-receptor subtypes. The present study aimed to investigate whether BM and NMB stimulate the proliferation of rat adrenocortical cells and to compare their mode of action. Adult female rats were treated with a single subcutaneous dose of 3 pg BM or NMB. Adrenocortical proliferative activity was assessed by the metaphase-arrest technique. BM administratio...

  9. Capsaicin treatment differentially affects feeding suppression by bombesin-like peptides

    OpenAIRE

    Ladenheim, Ellen E; Knipp, Susan

    2007-01-01

    Peripheral administration of bombesin (BN) and the related mammalian peptides, gastrin-releasing peptide (GRP) and neuromedin B (NMB), suppress food intake in rats. To examine whether all BN-like peptides utilize the same neural pathways to reduce feeding, rats were treated on postnatal day 2 with the injection vehicle or capsaicin, a neurotoxin that damages a subset of visceral afferent fibers. When rats reached adulthood, we compared the ability of a dose range of systemically administered ...

  10. High-affinity receptors for peptides of the bombesin family in Swiss 3T3 cells

    International Nuclear Information System (INIS)

    Gastrin-releasing peptide (GRP) labeled with 125I at tyrosine-15 (125I-GRP) binds to intact quiescent Swiss 3T3 cells in a specific and saturable manner. Scatchard analysis indicates the presence of a single class of high-affinity binding sites of Kd = 0.5 X 10(-9) M and a value for the number of sites per cell of about 100,000. 125I-GRP binding was not inhibited by other mitogens for these cells, and cell lines that are mitogenically unresponsive to GRP do not exhibit specific GRP binding. Structure-activity relationships show a close parallel between the ability of a range of GRP-related peptides to both inhibit GRP binding and to stimulate mitogenesis. Further, GRP binding is selectively blocked in a competitive fashion by a novel bombesin antagonist, [D-Arg1, D-Pro2, D-Trp7,9, Leu11] substance P. In addition, this compound selectively inhibits GRP and bombesin-induced mitogenesis. These results demonstrate that the mitogenic response of Swiss 3T3 cells to peptides of the bombesin family is mediated by a class of receptors distinct from those of other mitogens for these cells

  11. Bombesin, vasopressin, and endothelin rapidly stimulate tyrosine phosphorylation in intact Swiss 3T3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Zachary, I.; Gil, J.; Lehmann, W.; Sinnett-Smith, J.; Rozengurt, E. (Imperial Cancer Research Fund, London (England))

    1991-06-01

    The mitogenic neuropeptides bombesin and vasopressin markedly increased tyrosine and serine phosphorylation of multiple substrates in quiescent Swiss 3T3 fibroblasts, including two major bands of M{sub r} 90,000 and 115,000. Tyrosine phosphorylation of these proteins was increased as judged by immunoprecipitation of {sup 32}P{sub i}-labeled cells and immunoblotting of unlabeled cells with monoclonal antiphosphotyrosine antibodies, elution with phenyl phosphate, and phospho amino acid analysis. Phosphotyrosyl proteins generated by bombesin and vasopressin did not correspond either by apparent molecular weight or by immunological and biochemical criteria to several known tyrosine kinase substrates, including phospholipase C{sub {gamma}}, the microtubule-associated protein 2 kinase, GTPase-activating protein, or phosphatidylinositol kinase. The effect was rapid (within seconds), concentration dependent, and inhibited by specific receptor antagonists for both bombesin and vasopressin. The endothelin-related peptide, vasoactive intestinal contractor, also elicited a rapid and concentration-dependent tyrosine/serine phosphorylation of a similar set of substrates. These results demonstrate that neuropeptides, acting through receptors linked to GTP-binding proteins, stimulate tyrosine phosphorylation of a common set of substrates in quiescent Swiss 3T3 cells and suggest the existence of an additional signal transduction pathway in neuropeptide-induced mitogenesis.

  12. Pleiotropic effects of bombesin and neurotensin on intestinal mucosa: Not just trefoil peptides

    Institute of Scientific and Technical Information of China (English)

    Stelios F Assimakopoulos; Chrisoula D Scopa; Vassiliki N Nikolopoulou; Constantine E Vagianos

    2008-01-01

    Bombesin and neurotensin are neuropeptides which exert a wide spectrum of biological actions on gastrointestinal tissues influencing intestinal growth and adaptation, intestinal motility, blood flow, secretion, nutrient absorption and immune response. Based mainly on their well-established potent enterotrophic effect, numerous experimental studies investigated their potential positive effect on the atrophic or injured intestinal mucosa. These peptides proved to be effective mucosa-healing factors, but the potential molecular and cellular mechanisms for this action remained unresolved. In a recently published study (World J Gastroenterol 2008; 14 (8): 1222-1230), it was shown that their protective effect on the intestine in experimentally induced inflammatory bowel disease was related to anti-inflammatory, antioxidant and antiapoptotic actions. These results are in close agreement with our previous studies on jaundiced and hepatectomized rats that showed a regulatory effect of bombesin and neurotensin on critical cellular processes such as enterocyte' proliferation and death, oxidative stress and redox equilibrium, tight junctions' formation and function, and inflammatory response. The pleiotropic effects of bombesin and neurotensin on diverse types of intestinal injury may justify their consideration for clinical trials.

  13. Development of lutetium-labeled bombesin derivates: relationship between structure and diagnostic-therapeutic activity for prostate tumor

    International Nuclear Information System (INIS)

    Bombesin (BBN) receptors - in particular, the gastrin-releasing peptide (GRP) receptor peptide - have been shown to be massively over expressed in several human tumors types, including prostate cancer, and could be an alternative as target for its treatment by radionuclide therapy (RNT). A large number of BBN analogs had already been synthesized for this purpose and have shown to reduce tumor growth in mice. Nevertheless, most of the studied analogs exhibit high abdominal accumulation, especially in pancreas. This abdominal accumulation may represent a problem in clinical use of radiolabeled bombesin analogs probably due to serious side effects to patients. The goal of the present work was to radiolabel a novel series of bombesin derivatives with lutetium-177 and to evaluate the relationship between their structure and diagnostic-therapeutic activity for prostate tumor. The generic structure of studied peptides is DOTA-Phe-(Gly)n-BBN(6-14), where DOTA is the chelator, n is the number of glycine amino acids of Phe-(Gly)n spacer and BBN(6-14) is the bombesin sequence from the amino acid 6 to the amino acid 14. Preliminary studies were done to establish the ideal labeling conditions for obtaining the highest yield of labeled bombesin derivatives, determined by instant thin layer chromatography (ITLC-SG) and high performance liquid chromatography (HPLC). The stability of the preparations was evaluated either after storing at 2-8 degree C or incubation in human serum at 37 degree C and the partition coefficient was determined in n:octanol:water. In vivo studies were performed in both healthy Balb-c and Nude mice bearing PC-3 xenografts, in order to characterize the biological properties of labeled peptides. In vitro studies involved the evaluation of cold bombesin derivatives effect in PC-3 cells proliferation. Bombesin derivatives were successfully labeled with high yield at optimized conditions and exhibited high stability at 4 degree C. The analysis of the stability

  14. Molecular markers derived from bombesin for tumor diagnosis by SPECT and PET

    International Nuclear Information System (INIS)

    A high number of molecules have already been identified to have high affinity to some receptors overexpressed on tumour cells and the radiolabelling of those molecules offers the possibility of new compounds for tumour diagnosis and therapy by nuclear medicine. Among of those molecules, bombesin (BBN) has become focus of interest, as its BB2 receptors are known to be overexpressed in prostate, breast, colon, pancreatic and lung tumour, as long as glioblastomas and neuroblastomas. BBN agonists and antagonists have already been described for this purpose and promising results were obtained in preclinical studies. However, most of them exhibited high abdominal accumulation, especially in pancreas and intestines, which can compromise diagnosis accuracy and cause serious adverse effects in therapy. In this context, the goal of the present work to radiolabel new BBN derivatives with 111In and 68Ga and to evaluate their potential for BB2 positive tumors diagnosis by single photon emission tomography (SPECT) and positron emission tomography (PET). The structure of studied peptides was Q-YGn-BBN(6-14), where Q is the chelator, n is the number of glycine aminoacids in the spacer YGn and BBN(6-14) is the original bombesin sequence from the aminoacid 6 to 14. The derivative in which the last aminoacid (methionine, Met) was replaced by norleucine (Nle) was also evaluated. The experimental evaluation of the bombesin derivatives was divided into four steps: computational studies, molecular markers for SPECT, molecular markers for PET and toxicological studies. The theoretical partition (log P) and distribution (log D) coefficients were calculated for all bombesin derivatives conjugated to DTPA (diethylenetriaminepentaacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelators applying computational programmes. Bombesin derivatives for SPECT were developed by radiolabelling DTPA-conjugated bombesin derivatives with 111In to determine the best spacer

  15. Optimization of the production process of hybrid and multivalent formulation Bombesin/RGD for the opportune detection of breast cancer

    International Nuclear Information System (INIS)

    The radiopharmaceuticals of third generation are used in nuclear medicine to obtain images of specific molecular targets, and they are unique in their capacity to detect in vivo specific biochemical sites as receptors that are over-expressed in diverse illness. In cancer cells several types of receptors are over-expressed, as the integrin s α(v)β(3) and α(v)β(5) that specifically recognize the sequence RGD (Arginine-Glycin-Ac. Aspartic) and gastrin-releasing peptide that recognizes specifically to the peptide Lys3-Bombesin. The integrin s α(v)β(3) and α(v)β(5) are involved in the tumor angio genesis processes and the gastrin-releasing peptide is over-expressed in breast and prostate cancer. The molecular recognition of the specific receptors is the basis to be utilized as targets of the radiopharmaceuticals 99mTc-HYNIC-Bombesin and 99mTc-HYNIC-RGD. In this work was developed a lyophilized pharmaceutical formulation effective, stable and safe for the simultaneous obtaining of the radiopharmaceuticals 99mTc-HYNIC-Bombesin (99mTc-EDDA/HYNIC-Lys3-Bombesin) and 99mTc-HYNIC-RGD (99mTc EDDA/HYNIC-E-[c(RGDfK)]2). Later on the production process of the product HYNIC-Bombesin/RGD-Sn was optimized using a factorial design and the formulation was transferred to the production plant of radiopharmaceuticals of the Instituto Nacional de Investigaciones Nucleares (ININ). The optimized formulation is described in the following chart: HYNIC-[Lys3]-Bombesin - 12.5 μg; HYNIC-E-c[RGDfK]2 - 12.5 μg; Stannous chloride (SnCl2) - 20 μg; Ethylenediamine diacetic acid (EDDA) - 10 mg; N-tris(hydroxymethyl)methyl glycin (Tricine) - 20 mg; Mannitol - 50 mg. The production process was validated and were carried out the stability studies under refrigeration conditions. (Author)

  16. Inhibitory effect of bombesin and SMS 201-995 on DNA synthesis in the rat thyroid lobes incubated in vitro

    International Nuclear Information System (INIS)

    The effects of 4-h incubation in the presence of bombesin on the incorporation of [3H]-thymidine into DNA of the rat thyroid lobes, collected from animals treated in vivo with a long-acting somatostatin analog (SMS 201-995) or with 0.9% NaCl, were investigated. It was shown that not only in vivo injections of SMS 201-995, but also, unexpectedly, in vitro incubation with bombesin inhibited [3H]-thymidine incorporation. The two examined substances did not reveal any additive action in their inhibitory effects on the thyroid growth

  17. Bombesin receptor subtype-3 agonists stimulate the growth of lung cancer cells and increase EGF receptor tyrosine phosphorylation

    OpenAIRE

    Moody, Terry W.; Sancho, Veronica; Florio, Alessia di; Nuche-Berenguer, Bernardo; Mantey, Samuel; Jensen, Robert T.

    2011-01-01

    The effects of bombesin receptor subtype-3 (BRS-3) agonists were investigated on lung cancer cells. The BRS-3 agonist (DTyr6, βAla11, Phe13, Nle14)bombesin6-14 (BA1), but not gastrin releasing peptide (GRP) or neuromedin B (NMB) increased significantly the clonal growth of NCI-H1299 cells stably transfected with BRS-3 (NCI-H1299-BRS-3). Also, BA1 addition to NCI-H727 or NCI-H1299-BRS-3 cells caused Tyr1068 phosphorylation of the epidermal growth factor receptor (EGFR). Similarly, (DTyr6, R-Ap...

  18. Molecular cloning of a new bombesin receptor subtype expressed in uterus during pregnancy

    OpenAIRE

    Gorboulev, Valentin; Akhundova, Aida; Büchner, Hubert; Fahrenholz, Falk

    2011-01-01

    The homology screening approach has been used to clone a new member of the guanine-nucleotidebinding-protein-coupled receptor superfamily from guinea pig uterus. The cloned cDNA encodes a 399-amino-acid protein and shows the highest amino acid similarity to members of the bombesin receptor family; 52% and 47% similarity to the gastrin-releasing-peptide (GRP) receptor and the neuromedin-B receptor, respectively. Bindingexperiments with the stably transfected LLC-PK1 cell line expressing the ne...

  19. Molecular Basis for the Selectivity of the Mammalian Bombesin Peptide, Neuromedin B, for Its Receptor

    OpenAIRE

    González, Nieves; Nakagawa, Tomoo; Mantey, Samuel A.; Sancho, Veronica; Uehara, Hirotsugu; Katsuno, Tatsuro; Jensen, Robert T.

    2009-01-01

    The mammalian bombesin (Bn) peptides, neuromedin B (NMB) and gastrin-releasing peptide (GRP), have widespread actions in many tissues, and their effects are mediated by two closely related G-protein-coupled receptors, the NMBR and GRPR. Little is known about the structural determinants of NMBR selectivity for NMB, in contrast to GRP selectivity for the GRPR, which has been extensively studied. To provide insight, chimeric NMBR-GRPR loss-of-affinity and gain-of-affinity mutants were made, as w...

  20. Comparative pharmacology of bombesin receptor subtype-3, nonpeptide agonist MK-5046, a universal peptide agonist, and peptide antagonist Bantag-1 for human bombesin receptors.

    Science.gov (United States)

    Moreno, Paola; Mantey, Samuel A; Nuche-Berenguer, Bernardo; Reitman, Marc L; González, Nieves; Coy, David H; Jensen, Robert T

    2013-10-01

    Bombesin-receptor-subtype-3 (BRS-3) is an orphan G-protein-coupled receptor of the bombesin (Bn) family whose natural ligand is unknown and which does not bind any natural Bn-peptide with high affinity. It is present in the central nervous system, peripheral tissues, and tumors; however, its role in normal physiology/pathophysiology is largely unknown because of the lack of selective ligands. Recently, MK-5046 [(2S)-1,1,1-trifluoro-2-[4-(1H-pyrazol-1-yl)phenyl]-3-(4-{[1-(trifluoromethyl)cyclopropyl]methyl}-1H-imidazol-2-yl)propan-2-ol] and Bantag-1 [Boc-Phe-His-4-amino-5-cyclohexyl-2,4,5-trideoxypentonyl-Leu-(3-dimethylamino) benzylamide N-methylammonium trifluoroacetate], a nonpeptide agonist and a peptide antagonist, respectively, for BRS-3 have been described, but there have been limited studies on their pharmacology. We studied MK-5046 and Bantag-1 interactions with human Bn-receptors-human bombesin receptor subtype-3 (hBRS-3), gastrin-releasing peptide receptor (GRP-R), and neuromedin B receptor (NMB-R)-and compared them with the nonselective, peptide-agonist [d-Tyr6,βAla11,Phe13,Nle14]Bn-(6-14) (peptide #1). Receptor activation was detected by activation of phospholipase C (PLC), mitogen-activated protein kinase (MAPK), focal adhesion kinase (FAK), paxillin, and Akt. In hBRS-3 cells, the relative affinities were Bantag-1 (1.3 nM) > peptide #1 (2 nM) > MK-5046 (37-160 nM) > GRP, NMB (>10 μM), and the binding-dose-inhibition curves were broad (>4 logs), with Hill coefficients differing significantly from unity. Curve-fitting demonstrated high-affinity (MK-5046, Ki = 0.08 nM) and low-affinity (MK-5046, Ki = 11-29 nM) binding sites. For PLC activation in hBRS-3 cells, the relative potencies were MK-5046 (0.02 nM) > peptide #1 (6 nM) > GRP, NMB, Bantag-1 (>10 μM), and MK-5046 had a biphasic dose response, whereas peptide #1 was monophasic. Bantag-1 was a specific hBRS-3-antagonist. In hBRS-3 cells, MK-5046 was a full agonist for activation of MAPK, FAK, Akt

  1. Therapeutic Efficacy with Treatment-related Toxicities of {sup 177}Lu-labeled Bombesin Derivative for the Peptide Receptor Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Cheong; Cho, Eun Ha; Lee, So Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The gastrin-releasing peptide receptor (GRPR) has been shown to be overexpressed in many human tumours, including breast cancer, prostate cancer, small cell lung cancer, ovarian cancers, endometrial cancers, and gastrointestinal stromal tumors. In particular, GRPR expression is high in 83 % of invasive primary prostatic carcinomas. These results suggest that {sup 177}Lu-labeled bombesin derivative has promising characteristics as a novel nuclear medicine, especially for the treatment of GRPR over-expressing prostate tumors.

  2. Heterologous desensitization of bombesin-induced mitogenesis by prolonged exposure to vasopressin: a post-receptor signal transduction block.

    OpenAIRE

    Millar, J B; Rozengurt, E

    1989-01-01

    Prolonged exposure of quiescent Swiss 3T3 cells to vasopressin prevents mitogenic stimulation on subsequent addition of bombesin. This heterologous desensitization is selective and can be mimicked by vasopressin agonists, including [Lys8]vasopressin and oxytocin but not by the V1-type-specific vasopressin receptor antagonist [Pmp1,O-Me-Tyr2,Arg8]vasopressin [where Pmp is 1-(beta-mercapto-beta,beta-cyclopenthamethylene propionic acid)]. Furthermore, vasopressin-induced loss of responsiveness t...

  3. Ca2+-mobilizing actions of platelet-derived growth factor differ from those of bombesin and vasopressin in Swiss 3T3 mouse cells

    International Nuclear Information System (INIS)

    Addition of the mitogenic peptides bombesin and vasopressin to quiescent Swiss 3T3 mouse cells increased the cytosolic Ca2+ concentration without any measurable delay. In contrast, there was a significant lag period (16 +/- 1.2 s) before platelet-derived growth factor (PDGF) increased cytosolic Ca2+ concentration. This lag was not diminished at high concentrations of either porcine or human PDGF. Similar results were obtained in 3T3 cells loaded with quin-2 or fura-2. The differences in the effects of bombesin, vasopressin, and PDGF on Ca2+ movements were also substantiated by measurements of 45Ca2+ efflux and of cellular 45Ca2+ content. Activation of protein kinase C by phorbol esters inhibited Ca2+ mobilization induced by either bombesin or vasopressin. In contrast, phorbol esters had no effect on PDGF-induced cytosolic Ca2+ concentration increase or acceleration of 45Ca2+ efflux. Finally, bombesin and vasopressin caused a rapid increase in the production of inositol 1,4,5-trisphosphate and inositol 1,3,4-trisphosphate, whereas PDGF, even at a saturating concentration, exerted only a small effect. These results indicate that the signal transduction pathway activated by PDGF that lead to Ca2+ mobilization can be distinguished form those utilized by bombesin and vasopressin

  4. Selection of optimal chelator improves the contrast of GRPR imaging using bombesin analogue RM26.

    Science.gov (United States)

    Mitran, Bogdan; Varasteh, Zohreh; Selvaraju, Ram Kumar; Lindeberg, Gunnar; Sörensen, Jens; Larhed, Mats; Tolmachev, Vladimir; Rosenström, Ulrika; Orlova, Anna

    2016-05-01

    Bombesin (BN) analogs bind with high affinity to gastrin-releasing peptide receptors (GRPRs) that are up-regulated in prostate cancer and can be used for the visualization of prostate cancer. The aim of this study was to investigate the influence of radionuclide-chelator complexes on the biodistribution pattern of the 111In-labeled bombesin antagonist PEG2-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2 (PEG2-RM26) and to identify an optimal construct for SPECT imaging. A series of RM26 analogs N-terminally conjugated with NOTA, NODAGA, DOTA and DOTAGA via a PEG2 spacer were radiolabeled with 111In and evaluated both in vitro and in vivo. The conjugates were successfully labeled with 111In with 100% purity and retained binding specificity to GRPR and high stability. The cellular processing of all compounds was characterized by slow internalization. The IC50 values were in the low nanomolar range, with lower IC50 values for positively charged natIn-NOTA-PEG2-RM26 (2.6±0.1 nM) and higher values for negatively charged natIn-DOTAGA-PEG2-RM26 (4.8±0.5 nM). The kinetic binding studies showed KD values in the picomolar range that followed the same pattern as the IC50 data. The biodistribution of all compounds was studied in BALB/c nu/nu mice bearing PC-3 prostate cancer xenografts. Tumor targeting and biodistribution studies displayed rapid clearance of radioactivity from the blood and normal organs via kidney excretion. All conjugates showed similar uptake in tumors at 4 h p.i. The radioactivity accumulation in GRPR-expressing organs was significantly lower for DOTA- and DOTAGA-containing constructs compared to those containing NOTA and NODAGA. 111In-NOTA-PEG2-RM26 with a positively charged complex showed the highest initial uptake and the slowest clearance of radioactivity from the liver. At 4 h p.i., DOTA- and DOTAGA-coupled analogs showed significantly higher tumor-to-organ ratios compared to NOTA- and NODAGA-containing variants. The NODAGA conjugate demonstrated

  5. A role for bombesin in sensory processing in the spinal cord.

    Science.gov (United States)

    O'Donohue, T L; Massari, V J; Pazoles, C J; Chronwall, B M; Shults, C W; Quirion, R; Chase, T N; Moody, T W

    1984-12-01

    Bombesin (BN)-containing neuronal processes were demonstrated in laminae I and II of the dorsal horn of the cat, rat, and mouse spinal cord by immunocytochemistry and radioimmunoassay. Dorsal rhizotomy in the cat resulted in a marked decrease in BN immunoreactivity in the dorsal horn indicating that BN is contained in primary sensory afferents. BN-binding sites were also localized in superficial laminae of the dorsal horn. The presence of both BN and BN-binding sites in the dorsal horn suggested that BN may be involved in sensory processing in the spinal cord. Consistent with this hypothesis, it was demonstrated that an injection of BN into the spinal cord caused a biting and scratching response indicative of sensory stimulation. The effect was similar to that observed after injection of substance P into the cord with the exception that the BN effect lasted about 100 times longer than that induced by substance P. Taken together, these data indicate that BN may be a neurotransmitter of primary sensory afferents to the spinal cord. PMID:6094746

  6. Does bombesin-like peptide mediate radiation-induced anorexia and satiety?

    International Nuclear Information System (INIS)

    Bombesin (BN) and its mammalian counterpart gastrin-releasing peptide (GRP) act as neuroregulatory hormones and peripheral and central satiety-inducing agents. Previously, we demonstrated that irradiation induces an increase in the expression of BN/GRP in the innervation of the salivary glands in rats. We therefore carried out a study using radioimmunoassay (RIA) analysis and immunohistochemistry to examine whether saliva contains BN and whether irradiation affects the BN release to saliva in rats. Immunoreactivity for BN was detected not only in the innervation of the parenchyma but also in the duct cells and in the lumina of the ducts, suggesting entrance of BN into saliva. The RIA analysis confirmed that rat saliva contains a BN-like peptide. The observation shows that saliva contains this peptide but that there is no significant increase following the radiation schedule used. Nevertheless, the occurrence of an enhanced expression of BN in different peripheral tissues such as the salivary and laryngeal glands should be taken into consideration when discussing the clinically important problem of reduced food intake and anorexia in cancer patients. (orig.)

  7. Effects of peripheral and central bombesin on feeding behavior of rats.

    Science.gov (United States)

    Gibbs, J; Kulkosky, P J; Smith, G P

    1981-01-01

    Intraperitoneal injections of tetradecapeptide bombesin (BBS) produced large, dose-related suppressions of liquid and solid food intake in rats, with threshold doses of 1--2 micrograms-kg-1. The feeding-associated behaviors of rats receiving BBS by this route at a test meal were normally sequenced, and several other observations suggested that the effect of BBS was specific and not due to malaise. The structurally related amphibian peptide litorin and the structurally related mammalian gastrin-releasing peptide (GRP) produced similar suppressions of food intake. The satiety effect of BBS administered intraperitoneally did not require the accumulation of food in the gut, the presence of intact adrenals, the abdominal vagus, or the release of cholecystokinin. When BBS and cholecystokinin were administered simultaneous, the suppressive effects on food intake were additive. Lateral cerebroventricular injections of BBS also produced large, dose-related suppressions of food intake, with a threshold dose of 100 ng per rat. The effect by this route, however, was not behaviorally specific: BBS produced equivalent inhibitions of food and water intake at every point on the dose-response curve, and produced a marked increase in grooming which dominated the behavioral display. Thus, (1) peripheral BBS is a putative satiety signal in the rat; (2) the class (endocrine, paracrine, or neural) and mechanism of this satiety action is not established; and (3) the differences in specificity and behavior following intraperitoneal and cerebroventricular routes indicate that peripheral BBS does not act solely via the cerebrospinal fluid to elicity satiety. PMID:6283491

  8. Does bombesin-like peptide mediate radiation-induced anorexia and satiety?

    Energy Technology Data Exchange (ETDEWEB)

    Aalto, Y.; Franzen, L.; Henriksson, R. [Umeaa Univ. (Sweden). Dept. of Oncology; Forsgren, S.; Kjoerell, U. [Umeaa Univ. (Sweden). Dept. of Anatomy; Funegaard, U. [Umeaa Univ. (Sweden). Dept. of Cardiology

    1999-07-01

    Bombesin (BN) and its mammalian counterpart gastrin-releasing peptide (GRP) act as neuroregulatory hormones and peripheral and central satiety-inducing agents. Previously, we demonstrated that irradiation induces an increase in the expression of BN/GRP in the innervation of the salivary glands in rats. We therefore carried out a study using radioimmunoassay (RIA) analysis and immunohistochemistry to examine whether saliva contains BN and whether irradiation affects the BN release to saliva in rats. Immunoreactivity for BN was detected not only in the innervation of the parenchyma but also in the duct cells and in the lumina of the ducts, suggesting entrance of BN into saliva. The RIA analysis confirmed that rat saliva contains a BN-like peptide. The observation shows that saliva contains this peptide but that there is no significant increase following the radiation schedule used. Nevertheless, the occurrence of an enhanced expression of BN in different peripheral tissues such as the salivary and laryngeal glands should be taken into consideration when discussing the clinically important problem of reduced food intake and anorexia in cancer patients. (orig.)

  9. A Bombesin-Shepherdin Radioconjugate Designed for Combined Extra- and Intracellular Targeting

    Directory of Open Access Journals (Sweden)

    Christiane A. Fischer

    2014-05-01

    Full Text Available Radiolabeled peptides which target tumor-specific membrane structures of cancer cells represent a promising class of targeted radiopharmaceuticals for the diagnosis and therapy of cancer. A potential drawback of a number of reported radiopeptides is the rapid washout of a substantial fraction of the initially delivered radioactivity from cancer cells and tumors. This renders the initial targeting effort in part futile and results in a lower imaging quality and efficacy of the radiotracer than achievable. We are investigating the combination of internalizing radiopeptides with molecular entities specific for an intracellular target. By enabling intracellular interactions of the radioconjugate, we aim at reducing/decelerating the externalization of radioactivity from cancer cells. Using the “click-to-chelate” approach, the 99mTc-tricarbonyl core as a reporter probe for single-photon emission computed tomography (SPECT was combined with the binding sequence of bombesin for extracellular targeting of the gastrin-releasing peptide receptor (GRP-r and peptidic inhibitors of the cytosolic heat shock 90 protein (Hsp90 for intracellular targeting. Receptor-specific uptake of the multifunctional radioconjugate could be confirmed, however, the cellular washout of radioactivity was not improved. We assume that either endosomal trapping or lysosomal degradation of the radioconjugate is accountable for these observations.

  10. Inhibition of serotonin release by bombesin-like peptides in rat hypothalamus in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Saporito, M.S.; Warwick, R.O. Jr.

    1989-01-01

    We investigated the activity of bombesin (BN), neuromedin-C (NM-C) and neuromedin-B (NM-B) on serotonin (5-HT) release and reuptake in rat hypothalamus (HYP) in vitro. BN and NM-C but not NM-B decreased K/sup +/ evoked /sup 3/H-5-HT release from superfused HYP slices by 25%. Bacitracin, a nonspecific peptidase inhibitor, reversed the inhibitory effect of BN on K/sup +/ evoked /sup 3/H-5-HT release. Phosphoramidon (PAN, 10 /mu/M) an endopeptidase 24.11 inhibitor, abolished the inhibitory effect of BN, but not NM-C, on K/sup +/ evoked /sup 3/H-5-HT release. The peptidyl dipeptidase A inhibitor enalaprilat (ENP, 10 /mu/M), enhanced both BN and NM-C inhibition of /sup 3/H-5-HT release. Bestatin (BST, 10 /mu/M) had no effect on BN or NM-C inhibitory activity on /sup 3/H-5-HT release. Neither BN, NM-C nor NM-B affected reuptake of /sup 3/H-5-HT into HYP synaptosomes alone or in combination with any of the peptidase inhibitors, nor did these peptides alter the ability of fluoxetine to inhibit /sup 3/H-5-HT uptake.

  11. Insulinotropic action of bombesin-like peptides mediated by gastrin-releasing peptide receptors in steers.

    Science.gov (United States)

    Zhao, H Q; Yao, G; Yannaing, S; ThanThan, S; Kuwayama, H

    2016-01-01

    The present study characterizes the receptor that mediates the insulinotropic action of bombesin-like peptides (BLP) in ruminants. Eight Holstein steers were randomly and intravenously injected with synthetic bovine gastrin-releasing peptide (GRP; 0.9 nmol/kg BW), neuromedin B (NMB; 0.9 nmol/kg BW), or neuromedin C (NMC; 0.9 nmol/kg BW), each alone or combined with the antagonist of GRP receptors N-acetyl-GRP-OCHCH (N-GRP-EE; 22.5 nmol/kg BW) or the antagonist of GH secretagogue receptor type 1a (GHS-R1a) [D-Lys]-GHRP-6 (21.5 nmol/kg BW). Blood samples were collected at -10, 0 (just before injection), 5, 10, 15, 20, 30, 45, 60, 75, and 90 min relative to injection time. Levels of injected peptides, insulin, and glucose in plasma were analyzed. Results showed that the peak of insulin levels was seen at 5 min after injection of NMC or GRP. Plasma glucose was observed in 2 phases; a significant rise followed a remarkable fall after NMC or GRP administration compared with injection of the vehicle ( 0.05). These results indicated that the insulinotropic action of BLP is mediated by GRP receptors but not through a ghrelin/GHS-R1a pathway and that BLP may be involved in the regulation of glucose homeostasis in ruminants. PMID:26812312

  12. Experimental obstructive jaundice alters claudin-4 expression in intestinal mucosa: Effect of bombesin and neurotensin

    Institute of Scientific and Technical Information of China (English)

    Stelios F Assimakopoulos; Constantine E Vagianos; Aristides S Charonis; Ilias H Alexandris; Iris Spiliopoulou; Konstantinos C Thomopoulos; Vassiliki N Nikolopoulou; Chrisoula D Scopa

    2006-01-01

    AIM: To investigate the influence of experimental obstructive jaundice and exogenous bombesin (BBS) and neurotensin (NT) administration on the expression of the tight junction (TJ)-protein claudin-4 in intestinal epithelium of rats.METHODS: Forty male Wistar rats were randomly divided into five groups: Ⅰ = controls, Ⅱ = sham operated, Ⅲ = bile duct ligation (BDL), Ⅳ = BDL+BBS (30 μg/kg per d), V = BDL+NT (300 μg/kg per d). At the end of the experiment on d 10, endotoxin was measured in portal and aortic blood. Tissue sections of the terminal ileum were examined histologically and immunohistochemically for evaluation of claudin-4 expression in intestinal epithelium.RESULTS: Obstructive jaundice led to intestinal barrier failure demonstrated by significant portal and aortic endotoxemia. Claudin-4 expression was significantly increased in the upper third of the villi in jaundiced rats and an upregulation of its lateral distribution was noted.Administration of BBS or NT restored claudin-4 expression to the control state and significantly reduced portal and aortic endotoxemia.CONCLUSION: Experimental obstructive jaundice increases claudin-4 expression in intestinal epithelium,which may be a key factor contributing to the disruption of the mucosal barrier. Gut regulatory peptides BBS and NT can prevent this alteration and reduce portal and sysremic endotoxemia.

  13. 177Lu-Dendrimer Conjugated to Folate and Bombesin with Gold Nanoparticles in the Dendritic Cavity: A Potential Theranostic Radiopharmaceutical

    Directory of Open Access Journals (Sweden)

    Héctor Mendoza-Nava

    2016-01-01

    Full Text Available 177Lu-labeled nanoparticles conjugated to biomolecules have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this research was to synthesize 177Lu-dendrimer(PAMAM-G4-folate-bombesin with gold nanoparticles (AuNPs in the dendritic cavity and to evaluate the radiopharmaceutical potential for targeted radiotherapy and the simultaneous detection of folate receptors (FRs and gastrin-releasing peptide receptors (GRPRs overexpressed in breast cancer cells. p-SCN-Benzyl-DOTA was conjugated in aqueous-basic medium to the dendrimer. The carboxylate groups of Lys1Lys3(DOTA-bombesin and folic acid were activated with HATU and also conjugated to the dendrimer. The conjugate was mixed with 1% HAuCl4 followed by the addition of NaBH4 and purified by ultrafiltration. Elemental analysis (EDS, particle size distribution (DLS, TEM analysis, UV-Vis, and infrared and fluorescence spectroscopies were performed. The conjugate was radiolabeled using 177LuCl3 or 68GaCl3 and analyzed by radio-HPLC. Studies confirmed the dendrimer functionalization with high radiochemical purity (>95%. Fluorescence results demonstrated that the presence of AuNPs in the dendritic cavity confers useful photophysical properties to the radiopharmaceutical for optical imaging. Preliminary binding studies in T47D breast cancer cells showed a specific cell uptake (41.15±2.72%. 177Lu-dendrimer(AuNP-folate-bombesin may be useful as an optical and nuclear imaging agent for breast tumors overexpressing GRPR and FRs, as well as for targeted radiotherapy.

  14. Does the histaminergic system mediate bombesin/GRP-induced suppression of food intake?

    Science.gov (United States)

    Merali, Z; Banks, K

    1994-12-01

    Bombesin (BN) and its mammalian homologue, gastrin-releasing peptide (GRP), are potent satiety agents and have been implicated in the physiological regulation of food intake. The mechanism(s) of action of this effect remains unclear. There is a functional and anatomic overlap between histamine and BN in relationship to feeding, which led us to hypothesize that BN may mediate its satiety effects through activation of the histaminergic system. To assess this contention, we examined the effects of R-alpha-methylhistamine (alpha-MH) and Imetit, selective H3-receptor agonists that inhibit the release and synthesis of histamine, on BN- or cholecystokinin (CCK)-induced satiety. In this report we present the first evidence for the role of histamine H3 receptors in the mediation of BN-elicited satiety. During the first hour of the 4-h daily feeding session, BN reduced food intake by > 50% relative to the control condition; this suppression was blocked by prior treatment with the H3-receptor agonist, alpha-MH. This blockade of BN-induced satiety was dose related and selective to BN as alpha-MH failed to attenuate sulfated CCK-8-induced satiety. When alpha-MH was administered alone, it failed to significantly affect food intake. The specificity of this effect was further supported by the demonstration that another H3 agonist, Imetit, was also able to block the feeding-suppressant effects of BN. Furthermore, thioperamide, an H3-receptor antagonist, blocked these effects of Imetit.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Stress and eating: A dual role for bombesin-like peptides

    Directory of Open Access Journals (Sweden)

    Zul eMerali

    2013-10-01

    Full Text Available The current obesity ‘epidemic’ in the developed world is a major health concern; over half of adult Canadians are now classified as overweight or obese. Although the reasons for high obesity rates remain unknown, an important factor appears to be the role stressors play in overconsumption of food and weight gain. In this context, increased stressor exposure and/or perceived stress may influence eating behavior and food choices. Stress-induced anorexia is often noted in rats exposed to chronic stress (e.g. repeated restraint and access to standard Chow diet; associated reduced consumption and weight loss. However, if a similar stressor exposure takes place in the presence of palatable, calorie dense food, rats often consume an increase proportion of palatable food relative to Chow, leading to weight gain and obesity. In humans, a similar desire to eat palatable or ‘comfort’ foods has been noted under stressful situations; it is thought that this response may potentially be attributable to stress-buffering properties and/or through activation of reward pathways. The complex interplay between stress-induced anorexia and stress-induced obesity is discussed in terms of the overlapping circuitry and neurochemicals that mediate feeding, stress and reward pathways. In particular, this paper draws attention to the bombesin family of peptides (BBs initially shown to regulate food intake and subsequently shown to mediate stress response as well. Evidence is presented to support the hypothesis that BBs may be involved in stress-induced anorexia under certain conditions, but that the same peptides could also be involved in stress-induced obesity. This hypothesis is based on the unique distribution of BBs in key cortico-limbic brain regions involved in food regulation, reward, incentive salience and motivationally driven behavior.

  16. Characterization of the bombesin receptor on mouse pancreatic acini by chemical cross-linking

    Energy Technology Data Exchange (ETDEWEB)

    Huang, S.C.; Yu, D.H.; Wank, S.A.; Gardner, J.D.; Jensen, R.T. (National Institutes of Health, Bethesda, MD (USA))

    1990-11-01

    Bombesin (BN), gastrin-releasing peptide (GRP) and GRP(18-27) (neuromedin C) were equipotent and 30-fold more potent than neuromedin B (NMB) in inhibiting binding of {sup 125}I-GRP to and in stimulating amylase release from mouse pancreatic acini. In the present study we used {sup 125}I-GRP and chemical cross-linking techniques to characterize the mouse pancreatic BN receptor. After binding of {sup 125}I-GRP to membranes, and incubation with various chemical cross-linking agents, cross-linked radioactivity was analyzed by SDS-PAG electrophoresis and autoradiography. With each of 4 different chemical cross-linking agents, there was a single broad polypeptide band of Mr 80,000. Cross-linking did not occur in the absence of the cross-linking agent. Cross-linking was inhibited only by peptides that interact with the BN receptor such as GRP, NMB, GRP(18-27) or BN. Dose-inhibition curves for the ability of BN or NMB to inhibit binding of {sup 125}I-GRP to membranes or cross-linking to the 80,000 polypeptide demonstrated for both that BN was 15-fold more potent than NMB. The apparent molecular weight of the cross-linked polypeptide was unchanged by adding dithiothreitol. N-Glycanase treatment reduced the molecular weight of the cross-linked peptide to 40,000. The present results indicate that the BN receptor on mouse pancreatic acinar cell membranes resembles that recently described on various tumor cells in being a single glycoprotein with a molecular weight of 76,000. Because dithiothreitol had no effect, this glycoprotein is not a subunit of a larger disulfide-linked structure.

  17. GLP1- and GIP-producing cells rarely overlap and differ by bombesin receptor-2 expression and responsiveness.

    Science.gov (United States)

    Svendsen, Berit; Pais, Ramona; Engelstoft, Maja S; Milev, Nikolay B; Richards, Paul; Christiansen, Charlotte B; Egerod, Kristoffer L; Jensen, Signe M; Habib, Abdella M; Gribble, Fiona M; Schwartz, Thue W; Reimann, Frank; Holst, Jens J

    2016-01-01

    The incretin hormones glucagon-like peptide-1 (GLP1) and glucose-dependent insulinotropic polypeptide (GIP) are secreted from intestinal endocrine cells, the so-called L- and K-cells. The cells are derived from a common precursor and are highly related, and co-expression of the two hormones in so-called L/K-cells has been reported. To investigate the relationship between the GLP1- and GIP-producing cells more closely, we generated a transgenic mouse model expressing a fluorescent marker in GIP-positive cells. In combination with a mouse strain with fluorescent GLP1 cells, we were able to estimate the overlap between the two cell types. Furthermore, we used primary cultured intestinal cells and isolated perfused mouse intestine to measure the secretion of GIP and GLP1 in response to different stimuli. Overlapping GLP1 and GIP cells were rare (∼5%). KCl, glucose and forskolin+IBMX increased the secretion of both GLP1 and GIP, whereas bombesin/neuromedin C only stimulated GLP1 secretion. Expression analysis showed high expression of the bombesin 2 receptor in GLP1 positive cells, but no expression in GIP-positive cells. These data indicate both expressional and functional differences between the GLP1-producing 'L-cell' and the GIP-producing 'K-cell'. PMID:26483393

  18. Validation of the production process of core-equipment HYNIC-Bombesin-Sn; Validacion del proceso de produccion del nucleo-equipo HYNIC-Bombesina-Sn

    Energy Technology Data Exchange (ETDEWEB)

    Rubio C, N. I. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2008-07-01

    The validation process is establishing documented evidence that provides a high degree of assurance that a specific process consistently will produce a product that will meet specifications and quality attributes preset and, therefore, ensures the efficiency and effectiveness of a product. The radiopharmaceutical {sup 99m}Tc-HYNlC-Bombesin is part of the gastrin-releasing peptide (GRP) analogues of bombesin that are radiolabelled with technetium 99 metastable for molecular images obtention. Is obtained from freeze-dry formulations kits (core- equipment)) and has reported a very high stability in human serum, specific binding to receptors and rapid internalization. Biodistribution data in mice showed rapid blood clearance with predominant renal excretion and specific binding to tissues with positive response to GRP receptors. According to biokinetics studies performed on patients with breast cancer, breast show a marked asymmetry with increased uptake in neoplastic breast in healthy women and the uptake of radiopharmaceuticals is symmetrical in both breasts. No reported adverse reactions. In this paper, the prospective validation core-equipment HYNlC-Bombesin-Sn, which was shown consistently that the product meets the specifications and quality, attributes to preset from the obtained from the diagnostic radiopharmaceutical third generation: {sup 99m}Tc-HYNlC-Bombesin. The process was successfully validated and thereby ensuring the efficiency and effectiveness of this agent as a preliminary diagnostic for approval to be marketed. (Author)

  19. Study of the optical and dosimetric properties of the nano conjugate 99mTc-EDDA/HYNIC-GGC-Au Np-Bombesin by effect of nano particle size

    International Nuclear Information System (INIS)

    The receptors over-expressed on the surface of cancer cells represent promising targets for breast cancer diagnosis or therapy. The gastrin-releasing peptide receptor (GRP-r) is a seven-transmembrane G-protein coupled receptor that is over-expressed on primary prostate and breast cancer and lymph node metastases. Bombesin (Bn) is a tetradeca peptide that binds with high affinity to GRP-r. The strong, specific Bn-GRP-r binding is the basis for labelling Bn with radionuclides (i.e. 99mTc, 111In, 18F) to obtain molecular images. The aim of this work was to develop 3 multifunctional systems of 99mTc-labeled gold nanoparticles (Au Np) (5, 10 and 20 nm) conjugated to Lys3-Bombesin for GRP-receptor targeting in breast cancer. The systems were characterized by Tem and UV-Vis, IR, Raman, Fluorescence and XP spectroscopy. The 99mTc-Au Np-Lys3-Bombesin multifunctional system (20 nm) shows in vitro and in vivo specific recognition for GRP-r and suitable properties to be used as a nuclear molecular imaging agent. Results also showed a specific Lys3-Bombesin binding to the gold surface and higher fluorescence intensity for the 20 nm system. The Nir bands observed in the 20 nm radio conjugate indicate potential for bio imaging as dual systems. (Author)

  20. Development of a potent DOTA-conjugated bombesin antagonist for targeting GRPr-positive tumours

    Energy Technology Data Exchange (ETDEWEB)

    Mansi, Rosalba; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); University of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Wang, Xuejuan [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); Forrer, Flavio [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Erasmus Medical Centre, Nuclear Medicine, Rotterdam (Netherlands); Waser, Beatrice; Cescato, Renzo; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, Berne (Switzerland); Graham, Keith; Borkowski, Sandra [Bayer Schering Pharma AG, Global Drug Discovery, Berlin (Germany)

    2011-01-15

    Radiolabelled somatostatin-based antagonists show a higher uptake in tumour-bearing mouse models than agonists of similar or even distinctly higher receptor affinity. Very similar results were obtained with another family of G protein-coupled receptor ligands, the bombesin family. We describe a new conjugate, RM2, with the chelator DOTA coupled to D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH{sub 2} via the cationic spacer 4-amino-1-carboxymethyl-piperidine for labelling with radiometals such as {sup 111}In and {sup 68}Ga. RM2 was synthesized on a solid support and evaluated in vitro in PC-3 cells. IC{sub 50} and K{sub d} values were determined. The antagonist potency was evaluated by immunofluorescence-based internalization and Ca{sup 2+} mobilization assays. Biodistribution studies were performed in PC-3 and LNCaP tumour-bearing mice with {sup 111}In-RM2 and {sup 68}Ga-RM2, respectively. PET/CT studies were performed on PC-3 and LNCaP tumour-bearing nude mice with {sup 68}Ga-RM2. RM2 and {sup 111}In-RM2 are high-affinity and selective ligands for the GRP receptor (7.7{+-}3.3 nmol/l for RM2; 9.3{+-}3.3 nmol/l for {sup nat}In-RM2). The potent antagonistic properties were confirmed by an immunofluorescence-based internalization and Ca{sup 2+} mobilization assays. {sup 68}Ga- and {sup 111}In-RM2 showed high and specific uptake in both the tumour and the pancreas. Uptake in the tumour remained high (15.2{+-}4.8%IA/g at 1 h; 11.7{+-}2.4%IA/g at 4 h), whereas a relatively fast washout from the pancreas and the other abdominal organs was observed. Uptake in the pancreas decreased rapidly from 22.6{+-}4.7%IA/g at 1 h to 1.5{+-}0.5%IA/g at 4 h. RM2 was shown to be a potent GRPr antagonist. Pharmacokinetics and imaging studies indicate that {sup 111}In-RM2 and {sup 68}Ga-RM2 are ideal candidates for clinical SPECT and PET studies. (orig.)

  1. ML-18 is a non-peptide bombesin receptor subtype-3 antagonist which inhibits lung cancer growth.

    Science.gov (United States)

    Moody, Terry W; Mantey, Samuel A; Moreno, Paola; Nakamura, Taichi; Lacivita, Enza; Leopoldo, Marcello; Jensen, Robert T

    2015-02-01

    Bombesin receptor subtype (BRS)-3 is a G protein coupled receptor (GPCR) for the bombesin (BB)-family of peptides. BRS-3 is an orphan GPCR and little is known of its physiological role due to the lack of specific agonists and antagonists. PD168368 is a nonpeptide antagonist for the neuromedin B (NMB) receptor (R) whereas PD176252 is a nonpeptide antagonist for the gastrin releasing peptide (GRP) R and NMBR but not BRS-3. Here nonpeptide analogs of PD176252 e.g. the S-enantiomer ML-18, and the R-enantiomer, EMY-98, were investigated as BRS-3 antagonists using lung cancer cells. ML-18 and EMY-98 inhibited specific (125)I-BA1 (DTyr-Gln-Trp-Ala-Val-βAla-His-Phe-Nle-NH2)BB(6-14) binding to NCI-H1299 lung cancer cells stably transfected with BRS-3 with IC50 values of 4.8 and >100μM, respectively. In contrast, ML-18 bound with lower affinity to the GRPR and NMBR with IC50 values of 16 and >100μM, respectively. ML-18 (16μM), but not its enantiomer EMY-98, inhibited the ability of 10nM BA1 to elevate cytosolic Ca(2+) in a reversible manner using lung cancer cells loaded with FURA2-AM. ML-18 (16μM), but not EMY-98, inhibited the ability of 100nM BA1 to cause tyrosine phosphorylation of the EGFR and ERK in lung cancer cells. ML-18 but not EMY-98 inhibited the proliferation of lung cancer cells. The results indicate that ML-18 is a nonpeptide BRS-3 antagonist that should serve as a template to improve potency and selectivity. PMID:25554218

  2. Renal uptake and retention of radiolabeled somatostatin, bombesin, neurotensin, minigastrin and CCK analogues: species and gender differences

    Energy Technology Data Exchange (ETDEWEB)

    Melis, Marleen [Department of Nuclear Medicine, Erasmus MC Rotterdam, 3015 CE Rotterdam (Netherlands)], E-mail: m.melis@erasmusmc.nl; Krenning, Eric P.; Bernard, Bert F.; Visser, Monique de; Rolleman, Edgar; Jong, Marion de [Department of Nuclear Medicine, Erasmus MC Rotterdam, 3015 CE Rotterdam (Netherlands)

    2007-08-15

    Introduction: During therapy with radiolabeled peptides, the kidney is most often the critical organ. Newly developed peptides are evaluated preclinically in different animal models before their application in humans. In this study, the renal retention of several radiolabeled peptides was compared in male and female rats and mice. Methods: After intravenous injection of radiolabeled peptides [somatostatin, cholecystokinin (CCK), minigastrin, bombesin and neurotensin analogues], renal uptake was determined in both male and female Lewis rats and C57Bl mice. In addition, ex vivo autoradiography of renal sections was performed to localize accumulated radioactivity. Results: An equal distribution pattern of renal radioactivity was found for all peptides: high accumulation in the cortex, lower accumulation in the outer medulla and no radioactivity in the inner medulla of the kidneys. In both male rats and mice, an increasing renal uptake was found: [{sup 111}In-DTPA]CCK8<[{sup 111}In-DTPA-Pro{sup 1},Tyr{sup 4}]bombesin{approx}[{sup 111}In-DTPA] neurotensin<[{sup 111}In-DTPA]octreotide<<[{sup 111}In-DTPA]MG0. Renal uptake of [{sup 111}In-DTPA]octreotide in rats showed no gender difference, and renal radioactivity was about constant over time. In mice, however, renal uptake in females was significantly higher than that in males and decreased rapidly over time in both genders. Moreover, renal radioactivity in female mice injected with [{sup 111}In-DTPA]octreotide showed a different localization pattern. Conclusions: Regarding the renal uptake of different radiolabeled peptides, both species showed the same ranking order. Similar to findings in patients, rats showed comparable and constant renal retention of radioactivity in both genders, in contrast to mice. Therefore, rats appear to be the more favorable species for the study of the renal retention of radioactivity.

  3. Evaluation of 64Cu-labeled bifunctional chelate-bombesin conjugates.

    Science.gov (United States)

    Ait-Mohand, Samia; Fournier, Patrick; Dumulon-Perreault, Véronique; Kiefer, Garry E; Jurek, Paul; Ferreira, Cara L; Bénard, François; Guérin, Brigitte

    2011-08-17

    Several bifunctional chelates (BFCs) were investigated as carriers of (64)Cu for PET imaging. The most widely used chelator for (64)Cu labeling of BFCs is DOTA (1,4,7,10-tetraazacyclododecane-N,N',N″,N'''-tretraacetic acid), even though this complex exhibits only moderate in vivo stability. In this study, we prepared a series of alternative chelator-peptide conjugates labeled with (64)Cu, measured in vitro receptor binding affinities in human breast cancer T47D cells expressing the gastrin-releasing peptide receptor (GRPR) and compared their in vivo stability in mice. DOTA-, NOTA-(1,4,7-triazacyclononane-1,4,7-triacetic acid), PCTA-(3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene-3,6,9-triacetic acid), and Oxo-DO3A-(1-oxa-4,7,10-triazacyclododecane-4,7,10-triacetic acid) peptide conjugates were prepared using H(2)N-Aoc-[d-Tyr(6),βAla(11),Thi(13),Nle(14)]bombesin(6-14) (BBN) as a peptide template. The BBN moiety was selected since it binds with high affinity to the GRPR, which is overexpressed on human breast cancer cells. A convenient synthetic approach for the attachment of aniline-BFC to peptides on solid support is also presented. To facilitate the attachment of the aniline-PCTA and aniline-Oxo-DO3A to the peptide via an amide bond, a succinyl spacer was introduced at the N-terminus of BBN. The partially protected aniline-BFC (p-H(2)N-Bn-PCTA(Ot-Bu)(3) or p-H(2)N-Bn-DO3A(Ot-Bu)(3)) was then coupled to the resulting N-terminal carboxylic acid preactivated with DEPBT/ClHOBt on resin. After cleavage and purification, the peptide-conjugates were labeled with (64)Cu using [(64)Cu]Cu(OAc)(2) in 0.1 M ammonium acetate buffer at 100 °C for 15 min. Labeling efficacy was >90% for all peptides; Oxo-DO3A-BBN was incubated an additional 150 min at 100 °C to achieve this high yield. Specific activities varied from 76 to 101 TBq/mmol. Competition assays on T47D cells showed that all BFC-BBN complexes retained high affinity for the GRPR. All BFC-BBN (64)Cu

  4. Evaluation of {sup 99m}Tc-HYNIC-βAla-Bombesin{sub (7-14)} as an agent for pancreas tumor detection in mice

    Energy Technology Data Exchange (ETDEWEB)

    Carlesso, F.N.; Fuscaldi, L.L.; Araujo, R.S.; Teixeira, C.S.; Oliveira, M.C.; Fernandes, S.O.A.; Cassali, G.D.; Reis, D.C.; Barros, A.L.B.; Cardoso, V.N., E-mail: valbertcardoso@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2015-10-15

    Pancreatic adenocarcinoma is important in oncology because of its high mortality rate. Deaths may be avoided if an early diagnosis could be achieved. Several types of tumors overexpress gastrin-releasing peptide receptors (GRPr), including pancreatic cancer cells. Thus, a radiolabeled peptide derivative of gastrin-releasing peptide (GRP) may be useful as a specific imaging probe. The purpose of the present study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC--βAla-Bombesin{sub (7-14)} as an imaging probe for Capan-1 pancreatic adenocarcinoma. Xenographic pancreatic tumor was developed in nude mice and characterized by histopathological analysis. Biodistribution studies and scintigraphic images were carried out in tumor-bearing nude mice. The two methods showed higher uptake by pancreatic tumor when compared to muscle (used as control), and the tumor-to-muscle ratio indicated that {sup 99m}Tc-HYNIC--βAla-Bombesin{sub (7-14)} uptake was four-fold higher in tumor cells than in other tissues. Scintigraphic images also showed a clear signal at the tumor site. The present data indicate that {sup 99m}Tc-HYNIC--βAla-Bombesin{sub (7-14)} may be useful for the detection of pancreatic adenocarcinoma. (author)

  5. Development of lutetium-labeled bombesin derivates: relationship between structure and diagnostic-therapeutic activity for prostate tumor; Desenvolvimento de derivados da bombesina radiomarcados com lutecio-177: relacao estrutura e potencial diagnostico-terapeutico para tumor de prostata

    Energy Technology Data Exchange (ETDEWEB)

    Pujatti, Priscilla Brunelli

    2009-07-01

    Bombesin (BBN) receptors - in particular, the gastrin-releasing peptide (GRP) receptor peptide - have been shown to be massively over expressed in several human tumors types, including prostate cancer, and could be an alternative as target for its treatment by radionuclide therapy (RNT). A large number of BBN analogs had already been synthesized for this purpose and have shown to reduce tumor growth in mice. Nevertheless, most of the studied analogs exhibit high abdominal accumulation, especially in pancreas. This abdominal accumulation may represent a problem in clinical use of radiolabeled bombesin analogs probably due to serious side effects to patients. The goal of the present work was to radiolabel a novel series of bombesin derivatives with lutetium-177 and to evaluate the relationship between their structure and diagnostic-therapeutic activity for prostate tumor. The generic structure of studied peptides is DOTA-Phe-(Gly){sub n}-BBN(6-14), where DOTA is the chelator, n is the number of glycine amino acids of Phe-(Gly){sub n} spacer and BBN(6-14) is the bombesin sequence from the amino acid 6 to the amino acid 14. Preliminary studies were done to establish the ideal labeling conditions for obtaining the highest yield of labeled bombesin derivatives, determined by instant thin layer chromatography (ITLC-SG) and high performance liquid chromatography (HPLC). The stability of the preparations was evaluated either after storing at 2-8 degree C or incubation in human serum at 37 degree C and the partition coefficient was determined in n:octanol:water. In vivo studies were performed in both healthy Balb-c and Nude mice bearing PC-3 xenografts, in order to characterize the biological properties of labeled peptides. In vitro studies involved the evaluation of cold bombesin derivatives effect in PC-3 cells proliferation. Bombesin derivatives were successfully labeled with high yield at optimized conditions and exhibited high stability at 4 degree C. The analysis of

  6. Chemical and biological characterization of new Re(CO)3/[99mTc](CO)3 bombesin analogues

    International Nuclear Information System (INIS)

    Introduction: Bombesin, a neuropeptide with potential for breast and prostate tumor targeting, is rapidly metabolized in vivo, and as a result, uptake in tumor xenografts in mice is poor. An improvement can be expected from the introduction of nonnatural amino acids and spacers. Leu13 was replaced by cyclohexylalanine and Met14 by norleucine. Two spacers, -βAla-βAla- and 3,6-dioxa-8-aminooctanoic acid, were inserted between the receptor-binding amino acid sequence (7-14) of bombesin (BBS) and the retroNα-carboxymethyl histidine chelator used for labeling with the [99mTc](CO)3 core and the rhenium (Re) congener. Methods: The biological characterization of the new compounds was performed both in vitro on prostate carcinoma PC-3 cells (binding affinity, internalization/externalization) and in vivo (biodistribution in nude mice with tumor xenografts). The stability was also investigated in human plasma. The Re analogues were prepared for chemical characterization. Results: The nonnatural amino acids led to markedly slower degradation in human plasma and PC-3 cell cultures. The receptor affinity of the new technetium 99m ([99mTc])-labeled BBS analogues was similar to the unmodified compound with K d<1 nM. Uptake in the pancreas and in PC-3 tumor xenografts in nude mice was blocked by unlabeled BBS. The best target-to-nontarget uptake ratio was clearly due to the presence of the more polar spacer, -βAla-βAla-. Conclusions: The different spacers did not have a significant effect on stability or receptor affinity but had a clear influence on the uptake in healthy organs and tumors. Uptake in the kidneys was lower than in the liver, which is likely to be due to the lipophilicity of the compounds. A specific, high uptake was also observed in the gastrin-releasing peptide receptor-rich pancreas. Thus, with the introduction of spacers the in vivo properties of the compounds can be improved while leaving the affinity unaffected

  7. Pyrazolyl conjugates of bombesin: a new tridentate ligand framework for the stabilization of fac-[M(CO)3]+ moiety.

    Science.gov (United States)

    Alves, Susana; Correia, Joao D G; Santos, Isabel; Veerendra, Bhadrasetty; Sieckman, Gary L; Hoffman, Timothy J; Rold, Tammy L; Figueroa, Said Daibes; Retzloff, Lauren; McCrate, Joseph; Prasanphanich, Adam; Smith, Charles J

    2006-07-01

    We have described the synthesis of tridentate pyrazolyl ligand frameworks for coordination to the fac-[*M(CO)(3)](+) metal fragment (*M=(186/188)Re or (99m)Tc). These ligands impart a degree of kinetic inertness on the metal center, warranting their study in biological systems. We herein report in vitro/in vivo radiolabeling investigations of a new series of pyrazolyl bombesin (BBN) conjugates radiolabeled via the Isolink kit. These new conjugates are based on the general structure [(99m)Tc-pyrazolyl-X-BBN[7-14]NH(2)], where X=beta-alanine, serylserylserine or glycylglycylglycine. The pyrazolyl ligand is a tridentate ligand framework that coordinates the metal center through nitrogen donor atoms. The results of these investigations demonstrate the ability of these new conjugates to specifically target the gastrin-releasing peptide receptor subtype 2, which is overexpressed on human prostate PC-3 cancerous tissues. Therefore, these studies suggest the tridentate pyrazolyl ligand framework to be an ideal candidate for the design and development of low-valent (99m)Tc-based diagnostic radiopharmaceuticals based on BBN or other targeting vectors. PMID:16843837

  8. Comparison of estimated human effective dose of 67Ga- and 99mTc-labeled bombesin based on distribution data in mice

    International Nuclear Information System (INIS)

    This study describes the preparation, biodistribution and absorbed dose prediction of 67Ga and 99mTc labeled bombesin (BBN) in human organs, after injection in mice determined via medical internal radiation dose. We estimated that a 185-MBq injection of 67Ga-BBN into the humans would result in an estimated effective absorbed dose of 2.50 mSv whereas this value for 99mTc-BBN is 1.33 mSv in the whole body. These results suggest that injection of 67Ga-BBN would result 2 times higher absorbed dose compare to 99mTc-BBN. (author)

  9. Design, synthesis, and in vitro evaluation of cytotoxic analogs of bombesin-like peptides containing doxorubicin or its intensely potent derivative, 2-pyrrolinodoxorubicin

    OpenAIRE

    Nagy Attila; Armatis, Patricia; Cai, Ren-Zhi; Szepesházi Károly; Schally, Andrew V.; Halmos Gábor (1962-) (gyógyszerész, receptorfarmakológus, experimentális onkológus)

    1997-01-01

    Five peptide fragments, based on the C-terminal sequence of bombesin (BN)-(6-14) or BN-(7-14), were selected as carriers for radicals doxorubicin (DOX) and 2-pyrrolino-DOX to create hybrid cytotoxic analogs. All these compounds had a reduced peptide bond (CH2-NH or CH2-N) between positions 13 (Phe or Leu) and 14 (Phe, Leu, or Tac) (Tac = thiazolidine-4-carboxylic acid). Three pseudononapeptide carriers contained N-terminal d-Phe or d-Tpi at position 6 (Tpi = 2,3,4,9-tetrahydro-1H-pyrido[3,4-b...

  10. Biokinetics and dosimetry in patients of 99mTc-HYNIC-Lys3-Bombesin: images of GRP receptors

    International Nuclear Information System (INIS)

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [99mTc]EDDA/HYNIC-Lys3-bombesin (99mTc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using 99mTc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after 99mTc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99mTc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. 99mTc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red marrow). The mean effective dose was 3

  11. Comparative study of two different Bombesin derivates labeled with {sup 111}In and biodistribution in normal mice

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Ricardo S.; Alcarde, Lais F.; Correa, Beatriz L.; Massicano, Adriana V.F.; Couto, Renata M.; Mengatti, Jair; Araujo, Elaine B. de, E-mail: ricardooliveira@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Nuclear medicine is a medical speciality that uses radioactive compounds (radiopharmaceuticals), consisting of a substrate and a radioactive isotope, for diagnostic. Among the peptides of interest for Nuclear Medicine, bombesin (BBN), a 14 amino acid neuropeptide analog of human gastrin-releasing peptide, is one of the highlights. This is a comparative study aiming to establish the best condition to radiolabel two BBN derivatives, (DTPA-Phe-Gly{sub 5}-BBN{sub (6-14)}) and (DTPA-Phe-Gly{sub 2}-BBN{sub (6-14})) with 111-indium. Specific objectives of this study were evaluate a good condition of radiolabelling in search excellent specific activity the bombesin derivatives and determinate the biodistribution in health mice model. Ten micrograms (10μg) of the derivative DTPA-Phe-Gly2-BBN (6-14) was labeled with 18.5 MBq (0.5 mCi) of {sup 111}InCl{sub 3} at 25°C for different times (5, 15 and 30 minutes). The best condition was applied to peptide mass variation (10, 5, 2.5, 1, 0.5, 0.25 and 0.1 μg), keeping all other parameters fixed. Finally, the influence of {sup 111}InCl{sub 3} activity in the radiolabeling process (18.5, 37, 55.5, 74, 185 MBq) was evaluated. The best conditions were repeated for the second derivate, DTPA-Phe-Gly{sub 5}-BBN{sub (6-14}). The radiochemical purity was assessed by thin layer chromatography (TLC), using 0.2 M EDTA pH 5 as solvent, and high performance liquid chromatography (HPLC) with a C18 column with linear gradient 10% A to 90% A (v/v) (A: 0,1% of TFA in CH3CN; B: 0,1% of TFA in H2O) at a flow rate of 1 mL/minute for 15 minutes. Considering the reaction time, the higher radiochemical purity was obtained when 10μg of the peptide was labeled with 18.5 MBq (0.5 mCi) of {sup 111}In for 15 minutes at 25°C (97.33 ± 0.50%, n=3). In the mass variation study, the best results of radiochemical purity were obtained when 10 μg of the peptide was employed (97.69 ± 0.4%, n = 4). Finally, the maximum specific activity of the radiolabelled

  12. (18)F-AmBF3-MJ9: a novel radiofluorinated bombesin derivative for prostate cancer imaging.

    Science.gov (United States)

    Pourghiasian, Maral; Liu, Zhibo; Pan, Jinhe; Zhang, Zhengxing; Colpo, Nadine; Lin, Kuo-Shyan; Perrin, David M; Bénard, François

    2015-04-01

    A novel radiofluorinated derivative of bombesin, (18)F-AmBF3-MJ9, was synthesized and evaluated for its potential to image prostate cancer by targeting the gastrin releasing peptide receptor (GRPR). AmBF3-MJ9 was prepared from an ammoniomethyl-trifluoroborate (AmBF3) conjugated alkyne 2 and azidoacetyl-MJ9 via a copper-catalyzed click reaction, and had good binding affinity for GRPR (Ki=0.5±0.1nM). The (18)F-labeling was performed via a facile one-step (18)F-(19)F isotope exchange reaction, and (18)F-AmBF3-MJ9 was obtained in 23±5% (n=3) radiochemical yield in 25min with >99% radiochemical purity and 100±32GBq/μmol specific activity. (18)F-AmBF3-MJ9 was stable in mouse plasma, and was partially (22-30%) internalized after binding to GRPR. Positron emission tomography (PET) imaging and biodistribution studies in mice showed fast renal excretion and good uptake of (18)F-AmBF3-MJ9 by GRPR-expressing pancreas and PC-3 prostate cancer xenografts. Tumor uptake was 1.37±0.25%ID/g at 1h, and 2.20±0.13%ID/g at 2h post-injection (p.i.) with low background uptake and excellent tumor visualization (tumor-to-muscle ratios of 75.4±5.5). These data suggest that (18)F-AmBF3-MJ9 is a promising PET tracer for imaging GRPR-expressing prostate cancers.

  13. Molecular markers derived from bombesin for tumor diagnosis by SPECT and PET; Marcadores moleculares derivados da bombesina para diagnostico de tumores por SPECT e PET

    Energy Technology Data Exchange (ETDEWEB)

    Pujatti, Priscilla Brunelli

    2012-07-01

    A high number of molecules have already been identified to have high affinity to some receptors overexpressed on tumour cells and the radiolabelling of those molecules offers the possibility of new compounds for tumour diagnosis and therapy by nuclear medicine. Among of those molecules, bombesin (BBN) has become focus of interest, as its BB{sub 2} receptors are known to be overexpressed in prostate, breast, colon, pancreatic and lung tumour, as long as glioblastomas and neuroblastomas. BBN agonists and antagonists have already been described for this purpose and promising results were obtained in preclinical studies. However, most of them exhibited high abdominal accumulation, especially in pancreas and intestines, which can compromise diagnosis accuracy and cause serious adverse effects in therapy. In this context, the goal of the present work to radiolabel new BBN derivatives with {sup 11}1In and {sup 68}Ga and to evaluate their potential for BB{sub 2} positive tumors diagnosis by single photon emission tomography (SPECT) and positron emission tomography (PET). The structure of studied peptides was Q-YG{sub n}-BBN(6-14), where Q is the chelator, n is the number of glycine aminoacids in the spacer YG{sub n} and BBN(6-14) is the original bombesin sequence from the aminoacid 6 to 14. The derivative in which the last aminoacid (methionine, Met) was replaced by norleucine (Nle) was also evaluated. The experimental evaluation of the bombesin derivatives was divided into four steps: computational studies, molecular markers for SPECT, molecular markers for PET and toxicological studies. The theoretical partition (log P) and distribution (log D) coefficients were calculated for all bombesin derivatives conjugated to DTPA (diethylenetriaminepentaacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelators applying computational programmes. Bombesin derivatives for SPECT were developed by radiolabelling DTPA-conjugated bombesin derivatives with

  14. Molecular markers derived from bombesin for tumor diagnosis by SPECT and PET; Marcadores moleculares derivados da bombesina para diagnostico de tumores por SPECT e PET

    Energy Technology Data Exchange (ETDEWEB)

    Pujatti, Priscilla Brunelli

    2012-07-01

    A high number of molecules have already been identified to have high affinity to some receptors overexpressed on tumour cells and the radiolabelling of those molecules offers the possibility of new compounds for tumour diagnosis and therapy by nuclear medicine. Among of those molecules, bombesin (BBN) has become focus of interest, as its BB{sub 2} receptors are known to be overexpressed in prostate, breast, colon, pancreatic and lung tumour, as long as glioblastomas and neuroblastomas. BBN agonists and antagonists have already been described for this purpose and promising results were obtained in preclinical studies. However, most of them exhibited high abdominal accumulation, especially in pancreas and intestines, which can compromise diagnosis accuracy and cause serious adverse effects in therapy. In this context, the goal of the present work to radiolabel new BBN derivatives with {sup 11}1In and {sup 68}Ga and to evaluate their potential for BB{sub 2} positive tumors diagnosis by single photon emission tomography (SPECT) and positron emission tomography (PET). The structure of studied peptides was Q-YG{sub n}-BBN(6-14), where Q is the chelator, n is the number of glycine aminoacids in the spacer YG{sub n} and BBN(6-14) is the original bombesin sequence from the aminoacid 6 to 14. The derivative in which the last aminoacid (methionine, Met) was replaced by norleucine (Nle) was also evaluated. The experimental evaluation of the bombesin derivatives was divided into four steps: computational studies, molecular markers for SPECT, molecular markers for PET and toxicological studies. The theoretical partition (log P) and distribution (log D) coefficients were calculated for all bombesin derivatives conjugated to DTPA (diethylenetriaminepentaacetic acid) and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) chelators applying computational programmes. Bombesin derivatives for SPECT were developed by radiolabelling DTPA-conjugated bombesin derivatives with

  15. BLOCKADE OF ROSTRAL VENTROLATERAL MEDULLA (RVLM BOMBESIN RECEPTOR TYPE 1 DECREASES BLOOD PRESSURE AND SYMPATHETIC ACTIVITY IN ANESTHETIZED SPONTANEOUSLY HYPERTENSIVE RATS

    Directory of Open Access Journals (Sweden)

    Izabella Silva De Jesus Pinto

    2016-06-01

    Full Text Available IIntrathecal injection of bombesin (BBS promoted hypertensive and sympathoexcitatory effects in normotensive (NT rats. However, the involvement of rostral ventrolateral medulla (RVLM in these responses is still unclear. In the present study, we investigated: (1 the effects of BBS injected bilaterally into RVLM on cardiorespiratory and sympathetic activity in NT and spontaneously hypertensive rats (SHR; (2 the contribution of RVLM bombesin type 1 receptors (BB1 to the maintenance of hypertension in SHR. Urethane-anesthetized rats (1.2 g · kg−1, i.v. were instrumented to record mean arterial pressure (MAP, diaphragm (DIA motor and renal sympathetic nerve activity (RSNA. In NT rats and SHR, BBS (0.3 mM nanoinjected into RVLM increased MAP (33.9 ± 6.6 mmHg and 37.1 ± 4.5 mmHg, respectively; p < 0.05 and RSNA (97.8 ± 12.9 % and 84.5 ± 18.1 %, respectively; p < 0.05. In SHR, BBS also increased DIA burst amplitude (115.3 ± 22.7 %; p < 0.05. BB1 receptors antagonist (BIM-23127; 3 mM reduced MAP (-19.9 ± 4.4 mmHg; p < 0.05 and RSNA (-17.7 ± 3.8 %; p < 0.05 in SHR, but not in NT rats (-2.5 ± 2.8 mmHg; -2.7 ± 5.6 %, respectively. These results show that BBS can evoke sympathoexcitatory and pressor responses by activating RVLM BB1 receptors. This pathway might be involved in the maintenance of high levels of arterial blood pressure in SHR.

  16. Application of 99mTechnetium-HYNIC(tricine/TPPTS)-Aca-Bombesin(7-14) SPECT/CT in prostate cancer patients

    International Nuclear Information System (INIS)

    Rationale: The peptide bombesin (BBN) and its derivatives exhibit high binding affinity for the gastrin-releasing peptide receptor (GRPR), which is highly expressed in prostate cancer. We used the BBN-based radiopharmaceutical 99mTechnetium-HYNIC(tricine/TPPTS)-Aca-Bombesin(7-14) (99mTc-HABBN) to perform a first-in-man clinical pilot study to evaluate the feasibility of 99mTc-HABBN SPECT/CT for detection of prostate cancer in patients. Methods: Eight patients with biopsy-proven prostate cancer who were scheduled for either radical prostatectomy or external beam radiotherapy underwent 99mTc-HABBN scintigraphy and SPECT/CT prior to treatment. Serial blood samples were taken to assess blood radioactivity and to determine in vivo metabolic stability. Clinical parameters were measured and reported side effects, if present, were recorded. Prostate cancer specimens of all patients were immunohistochemically stained for GRPR. Results: 99mTc-HABBN was synthesized with high radiochemical yield, purity and specific activity. There were no significant changes in clinical parameters, and there were no adverse or subjective side effects. Low metabolic stability was observed, as less than 20% of 99mTc-HABBN was intact after 30 min. Immunohistochemical staining for GRPR was observed in the prostate cancer specimens in all patients. 99mTc-HABBN scintigraphy and SPECT/CT did not detect prostate cancer in patients with proven disease. Conclusions: 99mTc-HABBN SPECT/CT for visualization of prostate cancer is safe but hampered by an unexpected low in vivo metabolic stability in man. The difference between the excellent in vitro stability of 99mTc-HABBN in human serum samples determined in our previous study regarding 99mTc-HABBN and the low in vivo metabolic stability determined in this study, is striking. This issue warrants further study of peptide-based radiopharmaceuticals

  17. Monitoring β-arrestin recruitment via β-lactamase enzyme fragment complementation: purification of peptide E as a low-affinity ligand for mammalian bombesin receptors.

    Science.gov (United States)

    Ikeda, Yuichi; Kumagai, Hidetoshi; Okazaki, Hiroaki; Fujishiro, Mitsuhiro; Motozawa, Yoshihiro; Nomura, Seitaro; Takeda, Norifumi; Toko, Haruhiro; Takimoto, Eiki; Akazawa, Hiroshi; Morita, Hiroyuki; Suzuki, Jun-ichi; Yamazaki, Tsutomu; Komuro, Issei; Yanagisawa, Masashi

    2015-01-01

    Identification of cognate ligands for G protein-coupled receptors (GPCRs) provides a starting point for understanding novel regulatory mechanisms. Although GPCR ligands have typically been evaluated through the activation of heterotrimeric G proteins, recent studies have shown that GPCRs signal not only through G proteins but also through β-arrestins. As such, monitoring β-arrestin signaling instead of G protein signaling will increase the likelihood of identifying currently unknown ligands, including β-arrestin-biased agonists. Here, we developed a cell-based assay for monitoring ligand-dependent GPCR-β-arrestin interaction via β-lactamase enzyme fragment complementation. Inter alia, β-lactamase is a superior reporter enzyme because of its cell-permeable fluorescent substrate. This substrate makes the assay non-destructive and compatible with fluorescence-activated cell sorting (FACS). In a reporter cell, complementary fragments of β-lactamase (α and ω) were fused to β-arrestin 2 and GPCR, respectively. Ligand stimulation initiated the interaction of these chimeric proteins (β-arrestin-α and GPCR-ω), and this inducible interaction was measured through reconstituted β-lactamase activity. Utilizing this system, we screened various mammalian tissue extracts for agonistic activities on human bombesin receptor subtype 3 (hBRS3). We purified peptide E as a low-affinity ligand for hBRS3, which was also found to be an agonist for the other two mammalian bombesin receptors such as gastrin-releasing peptide receptor (GRPR) and neuromedin B receptor (NMBR). Successful purification of peptide E has validated the robustness of this assay. We conclude that our newly developed system will facilitate the discovery of GPCR ligands. PMID:26030739

  18. Monitoring β-arrestin recruitment via β-lactamase enzyme fragment complementation: purification of peptide E as a low-affinity ligand for mammalian bombesin receptors.

    Directory of Open Access Journals (Sweden)

    Yuichi Ikeda

    Full Text Available Identification of cognate ligands for G protein-coupled receptors (GPCRs provides a starting point for understanding novel regulatory mechanisms. Although GPCR ligands have typically been evaluated through the activation of heterotrimeric G proteins, recent studies have shown that GPCRs signal not only through G proteins but also through β-arrestins. As such, monitoring β-arrestin signaling instead of G protein signaling will increase the likelihood of identifying currently unknown ligands, including β-arrestin-biased agonists. Here, we developed a cell-based assay for monitoring ligand-dependent GPCR-β-arrestin interaction via β-lactamase enzyme fragment complementation. Inter alia, β-lactamase is a superior reporter enzyme because of its cell-permeable fluorescent substrate. This substrate makes the assay non-destructive and compatible with fluorescence-activated cell sorting (FACS. In a reporter cell, complementary fragments of β-lactamase (α and ω were fused to β-arrestin 2 and GPCR, respectively. Ligand stimulation initiated the interaction of these chimeric proteins (β-arrestin-α and GPCR-ω, and this inducible interaction was measured through reconstituted β-lactamase activity. Utilizing this system, we screened various mammalian tissue extracts for agonistic activities on human bombesin receptor subtype 3 (hBRS3. We purified peptide E as a low-affinity ligand for hBRS3, which was also found to be an agonist for the other two mammalian bombesin receptors such as gastrin-releasing peptide receptor (GRPR and neuromedin B receptor (NMBR. Successful purification of peptide E has validated the robustness of this assay. We conclude that our newly developed system will facilitate the discovery of GPCR ligands.

  19. Ameliorative effects of bombesin and neurotensin on trinitrobenzene sulphonic acid-induced colitis, oxidative damage and apoptosis in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM: To investigate the effects of bombesin (BBS) and neurotensin (NTS) on apoptosis and colitis in an ulcerative colitis model. METHODS: In this study, a total of 50 rats were divided equally into 5 groups. In the control group, no colitis induction or drug administration was performed. Colitis was induced in all other groups. Following the induction of colitis, BBS, NTS or both were applied to three groups of rats. The remaining group (colitis group) received no treatment. On the 11th d after induction of colitis and drug treatment, blood samples were collected for TNF-α and IL-6 level studies. Malondialdehyde (MDA), carbonyl, myeloperoxidase (MPO) and caspase-3 activities, as well as histopathological findings, evaluated in colonic tissues. RESULTS: According to the macroscopic and microscopic findings, the study groups treated with BBS,NTS and BBS+NTS showed significantly lower damage and inflammation compared with the colitis group (macroscopic score,2.1±0.87,3.7±0.94 and 2.1±0.87 vs 7.3 ± 0.94; microscopic score,2.0 ±0.66,3.3±0.82 and 1.8±0.63 vs 5.2±0.78,P<0.01=.TNF-αand IL-6 levels were increased significantly in all groups compared with the control group. These increases were significantly smaller in the BBS,NTS and BBS+NTS groups compared with the colitis group (TNF-α levels,169.69±53.56,245.86±64.85 and 175.54 4±42.19vs 556.44±49.82; IL-6 levels,443.30±53.99,612.80±70.39 and 396.80±78.43 vs 1505.90±222.23,P<0.05=.The colonic MPO and MDA levels were significantly lower in control, BBS, NTS and BBS+NTS groups than in the colitis group (MPO levels,24.36±8.10,40.51±8.67 and 25.83±6.43 vs 161.47±38.24; MDA levels,4.70±1.41,6.55±1.12 and 4.51±0.54 vs15.60±1.88,P<0.05=.Carbonyl content and caspase-3 levels were higher in the colitis and NTS groups than in control, BBS and BBS+NTS groups (carbonyl levels,553.99±59.58and 336.26±35.72 vs 209.76±30.92,219.76±25.77and 220.34 36.95; caspase-3 levels,451.70±68.27and 216.20

  20. Progress of radiolabelled bombesin in diagnosis and treatment of prostate cancer%放射性核素标记铃蟾肽在前列腺癌诊治中的研究进展

    Institute of Scientific and Technical Information of China (English)

    邢岩; 赵晋华

    2010-01-01

    前列腺癌等多种肿瘤细胞表面能过度表达铃蟾肽受体,因此,铃蟾肽及其受体可以作为靶点进行放射性核素受体显像及靶向治疗肿瘤,并成为近年来诊治前列腺癌的研究热点.该文综述了放射性核素标记铃蟾肽在前列腺癌显像及治疗方面的研究进展.%Studies show that high expression of bombesin exist in the face of many kind of tumors such as prostate cancer, so bombesin and its receptor can be used as target in radionuclide receptor imaging and targeted therapy of tumor, and become the focus of prostate cancer research. This article reviews the progress of radiolabelled bombesin in prostate cancer imaging and therapy.

  1. Effect of the peptide Tat(49-57) on the bio-distribution and similar radiopharmaceuticals dosimetry of the bombesin

    International Nuclear Information System (INIS)

    The gastrin-releasing peptide receptor (GRP-r) is over-expressed in prostate and breast cancer. 99mTc-Bombesin (99mTc-Bn) has been reported as a radiopharmaceutical with specific cell GRP-r binding. The HIV Tat(49-57)-derived peptide has been used to deliver a large variety of molecules to cell nuclei. New hybrid radiopharmaceuticals of type 99mTc-N2S2-Tat(49-57)-Lys3-Bn (99mTc-Tat-Bn) and 188Re-N2S2-Tat(49-57)-Lys3-Bn (188Re-Tat-Bn), would increase cell uptake and internalized in cancer cell nuclei could act as an effective system of targeted radiotherapy using Auger and internal conversion (I C) electron emissions near DNA. The aim of this research was to prepare and assess in vitro and in vivo uptake kinetics in cancer cells of 99mTc/188Re-Tat-Bn and the in vitro nucleus and cytoplasm internalization kinetics in GRP receptor-positive cancer cells as well as to evaluate the subcellular-level radiation absorbed dose associated with the observed effect on cancer cell DNA proliferation. Structures of N2S2-Tat-Bn and Tc/Re(O)N2S2-Tat-Bn were calculated by an Mm procedure. 99mTc-Tat-Bn and 188Re-Tat-Bn were synthesized and stability studies carried out by HPLC and I TLC-Sg analyses in serum and cysteine solutions. In vitro internalization was tested using human prostate cancer Pc 3 cells and breast carcinoma cell lines MDA-Mb 231 and MCF 7. Nuclei from cells were isolated using a nuclear extraction kit. Total disintegrations in each subcellular compartment were calculated by integration of experimental time activity kinetic curves. Nucleus internalization was corroborated by con focal microscopy images using immunofluorescent labelled Tat-Bn. Biodistribution was determined in Pc 3 tumor-bearing nude mice. The Penelope code was used to simulate and calculate the absorbed dose by contribution of β, Auger and I C electrons in the cytoplasm and nucleus using geometric models built from immunofluorescent cell images. A cell proliferation kit was used to evaluate DNA

  2. Chemical and biological characterization of new Re(CO){sub 3}/[{sup 99m}Tc](CO){sub 3} bombesin analogues

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Garayoa, Elisa [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland)]. E-mail: elisa.garcia@psi.ch; Rueegg, Dominique [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland); Blaeuenstein, Peter [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland); Zwimpfer, Martin [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland); Khan, Irfan Ullah [Institute of Biochemistry, Faculty of Bioscience, Pharmacy and Psychology, University of Leipzig, Bruederstrasse 34, D-04103 Leipzig (Germany); Maes, Veronique [Department of Organic Chemistry, Vrije Universiteit Brussel, 1050 Brussels (Belgium); Blanc, Alain [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland); Beck-Sickinger, Annette G. [Institute of Biochemistry, Faculty of Bioscience, Pharmacy and Psychology, University of Leipzig, Bruederstrasse 34, D-04103 Leipzig (Germany); Tourwe, Dirk A. [Department of Organic Chemistry, Vrije Universiteit Brussel, 1050 Brussels (Belgium); Schubiger, P. August [Paul Scherrer Institute, Centre for Radiopharmaceutical Science, CH-5232 Villigen PSI (Switzerland)

    2007-01-15

    Introduction: Bombesin, a neuropeptide with potential for breast and prostate tumor targeting, is rapidly metabolized in vivo, and as a result, uptake in tumor xenografts in mice is poor. An improvement can be expected from the introduction of nonnatural amino acids and spacers. Leu{sup 13} was replaced by cyclohexylalanine and Met{sup 14} by norleucine. Two spacers, -{beta}Ala-{beta}Ala- and 3,6-dioxa-8-aminooctanoic acid, were inserted between the receptor-binding amino acid sequence (7-14) of bombesin (BBS) and the retroN{sup {alpha}}-carboxymethyl histidine chelator used for labeling with the [{sup 99m}Tc](CO){sub 3} core and the rhenium (Re) congener. Methods: The biological characterization of the new compounds was performed both in vitro on prostate carcinoma PC-3 cells (binding affinity, internalization/externalization) and in vivo (biodistribution in nude mice with tumor xenografts). The stability was also investigated in human plasma. The Re analogues were prepared for chemical characterization. Results: The nonnatural amino acids led to markedly slower degradation in human plasma and PC-3 cell cultures. The receptor affinity of the new technetium 99m ([{sup 99m}Tc])-labeled BBS analogues was similar to the unmodified compound with K {sub d}<1 nM. Uptake in the pancreas and in PC-3 tumor xenografts in nude mice was blocked by unlabeled BBS. The best target-to-nontarget uptake ratio was clearly due to the presence of the more polar spacer, -{beta}Ala-{beta}Ala-. Conclusions: The different spacers did not have a significant effect on stability or receptor affinity but had a clear influence on the uptake in healthy organs and tumors. Uptake in the kidneys was lower than in the liver, which is likely to be due to the lipophilicity of the compounds. A specific, high uptake was also observed in the gastrin-releasing peptide receptor-rich pancreas. Thus, with the introduction of spacers the in vivo properties of the compounds can be improved while leaving the

  3. Biokinetics and dosimetry of {sup 99m} Tc-EDDA/HYNIC-[Lys{sup 3}]-bombesin in humans: imaging of GRP receptors

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C.L.; Ferro F, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Murphy, C.A de [INCMNSZ, 14000 Mexico D.F. (Mexico); Cardena, E.; Pichardo R, P. [Departamento de Medicina Nuclear, Oncologia Centro Medico Siglo XXI, Mexico D.F. (Mexico)

    2007-07-01

    Full text: Bombesin (BN) receptor subtype 2 (GRP-r) is over-expressed on various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently we reported the {sup 99-}mTc-EDDA/HYNIC-[Lys{sup 3}]-Bombesin ({sup 99m}Tc-HYNIC-BN) complex as a new radiopharmaceutical with high stability in human serum, specific cell GRP-receptor binding and rapid internalization. The aim of this study was to evaluate the {sup 99m}Tc-HYNIC-BN biokinetics and dosimetry in 5-healthy and 3-breast cancer women. Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source' organs on each time frame. The same set of ROIs was used for all 8 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time activity curves in each organ, to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed a rapid radiopharmaceutical blood clearance with predominantly renal excretion and minimal hepatobiliary elimination. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in breast cancer lesions and well differentiated from GRP-r expression in lungs and airways with normal GRP-r density (ratio 3:1). The equivalent doses for a study using 370 MBq were 7.38{+-}1.68, 0.59{+-}0.08, 2.07{+-}0.60, 0.58{+-}0.1, 0.75{+-}0.09 and 0.43{+-}0.07 mSv for kidneys, liver, lungs, ovaries, pancreas and red marrow respectively. The effective dose was 1.64{+-}0.25 mSv which is comparable with the doses known for most of the {sup 99m}Tc radiopharmaceutical studies in nuclear medicine. (Author)

  4. Deafferentation causes a loss of presynaptic bombesin receptors and supersensitivity of substance P receptors in the dorsal horn of the cat spinal cord.

    Science.gov (United States)

    Massari, V J; Shults, C W; Park, C H; Tizabi, Y; Moody, T W; Chronwall, B M; Culver, M; Chase, T N

    1985-09-23

    Bombesin (BN)- and substance P (SP)-containing neurons are found in the dorsal root ganglia, and project to the dorsal horn of the spinal cord. The present study was undertaken to determine if chronic deafferentation of the cat spinal cord would affect BN or SP receptors in the spinal cord. Ten and 30 days after a unilateral lumbosacral dorsal rhizotomy, BN and SP receptor binding was evaluated autoradiographically using iodinated ligands to bind to these receptors in vitro. The normal distribution of BN receptors detected by this method was restricted to the head of the dorsal horn. Deafferentation caused a 38% and 22% decline in BN receptor binding in laminae I-IV at 10 or 30 days postoperatively, respectively. These data suggest that 'presynaptic' BN receptors are found on the central nervous system terminals of primary sensory afferents. Normal SP receptor distribution was most dense in lamina X, not in the superficial laminae of the dorsal horn. Deafferentation caused an initial decline in SP receptor binding in laminae I-II, followed by a 14% increase at 30 days in comparison to the unoperated side of the spinal cord. This delayed supersensitivity of SP receptors was confirmed in a separate experiment using a homogenate binding assay. These data are discussed with respect to the potential roles of receptor supersensitivity or subsensitivity in the development of deafferentation-induced changes in reactivity of dorsal horn neurons to nociceptive and non-nociceptive stimuli. PMID:2413960

  5. In vitro Evaluation of a Bombesin Antagonistic Analogue Conjugated with DOTA-Ala(SO{sub 3}H)-Aminooctanoyl for Targeting of the Gastrin-releasing Peptide Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Cheong; Cho, Eun Ha; Kim, Jin Joo; Lee, So Young; Choi, Sang Mu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    As Bombesin (BBS) binds with high affinity to GRPR, BBS derivatives have been labeled with various radionuclides such as {sup 99}mTc, {sup 111}In, {sup 90}Y, {sup 64}Cu, {sup 177}Lu, {sup 68}Ga, or {sup 18}F and have proved to be successful candidates for peptide receptor radiotherapy (PRRT). In this study, we employed Ala(SO{sub 3}H)-Aminooctanoyl as a linker of BBS antagonistic peptide sequence, Gln-Trp-Ala-Val-N methyl Gly-His-Statine-Leu-NH{sub 2}, with DOTA to prepare radiolabeled candidates for GRPR targeting. A DOTA-conjugated BBS antagonistic analogue was synthesized and radiolabeled with {sup 177}Lu, and in vitro characteristics on GRPR-overexpressing human prostate tumor cells were evaluated. In conclusion, a novel BBS antagonistic analogue, {sup 177}Lu-DOTA-sBBNA, is a promising candidate for the targeting of GRPR-over-expressing tumors. Further investigations to evaluate its in vivo characteristics and therapeutic efficacy are needed.

  6. Blockade of Rostral Ventrolateral Medulla (RVLM) Bombesin Receptor Type 1 Decreases Blood Pressure and Sympathetic Activity in Anesthetized Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Pinto, Izabella S; Mourão, Aline A; da Silva, Elaine F; Camargo, Amanda S; Marques, Stefanne M; Gomes, Karina P; Fajemiroye, James O; da Silva Reis, Angela A; Rebelo, Ana C S; Ferreira-Neto, Marcos L; Rosa, Daniel A; Freiria-Oliveira, André H; Castro, Carlos H; Colombari, Eduardo; Colugnati, Diego B; Pedrino, Gustavo R

    2016-01-01

    Intrathecal injection of bombesin (BBS) promoted hypertensive and sympathoexcitatory effects in normotensive (NT) rats. However, the involvement of rostral ventrolateral medulla (RVLM) in these responses is still unclear. In the present study, we investigated: (1) the effects of BBS injected bilaterally into RVLM on cardiorespiratory and sympathetic activity in NT and spontaneously hypertensive rats (SHR); (2) the contribution of RVLM BBS type 1 receptors (BB1) to the maintenance of hypertension in SHR. Urethane-anesthetized rats (1.2 g · kg(-1), i.v.) were instrumented to record mean arterial pressure (MAP), diaphragm (DIA) motor, and renal sympathetic nerve activity (RSNA). In NT rats and SHR, BBS (0.3 mM) nanoinjected into RVLM increased MAP (33.9 ± 6.6 and 37.1 ± 4.5 mmHg, respectively; p BIM-23127; 3 mM) reduced MAP (-19.9 ± 4.4 mmHg; p < 0.05) and RSNA (-17.7 ± 3.8%; p < 0.05) in SHR, but not in NT rats (-2.5 ± 2.8 mmHg; -2.7 ± 5.6%, respectively). These results show that BBS can evoke sympathoexcitatory and pressor responses by activating RVLM BB1 receptors. This pathway might be involved in the maintenance of high levels of arterial blood pressure in SHR. PMID:27313544

  7. Synthesis and characterization of Bombesin-superparamagnetic iron oxide nanoparticles as a targeted contrast agent for imaging of breast cancer using MRI

    International Nuclear Information System (INIS)

    The targeted delivery of superparamagnetic iron oxide nanoparticles (SPIONs) as a contrast agent may facilitate their accumulation in cancer cells and enhance the sensitivity of MR imaging. In this study, SPIONs coated with dextran (DSPIONs) were conjugated with bombesin (BBN) to produce a targeting contrast agent for detection of breast cancer using MRI. X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer analyses indicated the formation of dextran-coated superparamagnetic iron oxide nanoparticles with an average size of 6.0 ± 0.5 nm. Fourier transform infrared spectroscopy confirmed the conjugation of the BBN with the DSPIONs. A stability study proved the high optical stability of DSPION–BBN in human blood serum. DSPION–BBN biocompatibility was confirmed by cytotoxicity evaluation. A binding study showed the targeting ability of DSPION–BBN to bind to T47D breast cancer cells overexpressing gastrin-releasing peptide (GRP) receptors. T2-weighted and T2*-weighted color map MR images were acquired. The MRI study indicated that the DSPION–BBN possessed good diagnostic ability as a GRP-specific contrast agent, with appropriate signal reduction in T2*-weighted color map MR images in mice with breast tumors. (paper)

  8. Pyrazolyl conjugates of bombesin: a new tridentate ligand framework for the stabilization of fac-[M(CO){sub 3}]{sup +} moiety

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Susana; Correia, Joao D.G.; Santos, Isabel [Departamento de Quimica, Instituto Tecnologico e Nuclear, 2686-953 Sacavem (Portugal); Veerendra, Bhadrasetty [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Sieckman, Gary L. [Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); Hoffman, Timothy J. [Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States)]|[Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States)]|[Radiopharmaceutical Sciences Institute, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Rold, Tammy L. [Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Figueroa, Said Daibes [Radiopharmaceutical Sciences Institute, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Retzloff, Lauren [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); McCrate, Joseph [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Prasanphanich, Adam [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Smith, Charles J. [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States)]|[University of Missouri Research Reactor Center, University of Missouri-Columbia, Columbia, MO 65211 (United States)]|[Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States)]|[Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States)]. E-mail: smithcj@health.missouri.edu

    2006-07-15

    We have described the synthesis of tridentate pyrazolyl ligand frameworks for coordination to the fac-[*M(CO){sub 3}]{sup +} metal fragment (*M={sup 186/188}Re or {sup 99m}Tc). These ligands impart a degree of kinetic inertness on the metal center, warranting their study in biological systems. We herein report in vitro/in vivo radiolabeling investigations of a new series of pyrazolyl bombesin (BBN) conjugates radiolabeled via the Isolink kit. These new conjugates are based on the general structure [{sup 99m}Tc-pyrazolyl-X-BBN[7-14]NH{sub 2}], where X={beta}-alanine, serylserylserine or glycylglycylglycine. The pyrazolyl ligand is a tridentate ligand framework that coordinates the metal center through nitrogen donor atoms. The results of these investigations demonstrate the ability of these new conjugates to specifically target the gastrin-releasing peptide receptor subtype 2, which is overexpressed on human prostate PC-3 cancerous tissues. Therefore, these studies suggest the tridentate pyrazolyl ligand framework to be an ideal candidate for the design and development of low-valent {sup 99m}Tc-based diagnostic radiopharmaceuticals based on BBN or other targeting vectors.

  9. Synthesis and evaluation of Lys{sup 1}(α, γ-Folate)Lys{sup 3}({sup 177}Lu-DOTA)-Bombesin(1-14) as a potential theranostic radiopharmaceutical for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Aranda L, L.; Ferro F, G.; Azorin V, E.; Ramirez, F. M.; Ocampo G, B.; Santos C, C.; Jimenez M, N. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Issac O, K. [Universidad Autonoma del Estado de Mexico, Facultad de Medicina, 50180 Toluca, Estado de Mexico (Mexico)

    2015-10-15

    Full text: Lutetium-177 labeled hetero bivalent molecules that interact with different targets on tumor cells have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this work was to synthesize Lys{sup 1} (α,γ-Folate)-Lys{sup 3}({sup 177}Lu-DOTA)-Bombesin (1-14) ({sup 177}LuFolate-Bn), as well as to assess its in vitro and in vivo potential for molecular imaging and targeted radiotherapy of breast tumors expressing folate receptors (Fr) and gastrin releasing peptide receptors (GRPR). Lys{sup 1} Lys{sup 3} (DOTA)-Bombesin (1-14) was conjugated to the terminal carboxylic group of the folic acid and the product purified by size-exclusion HPLC. Chemical characterization was carried out by UV-vis, Ft-IR spectroscopies and MALDI-TOF mass spectrometry. {sup 177}Lu labeling was performed by reaction of {sup 177}LuCl{sub 3} with the Lys{sup 1} (α,γ-Folate)-Lys{sup 3} (DOTA)-Bombesin (Folate-Bn) conjugate. In vitro binding studies were carried out in T47D breast cancer cells (positive to Fr and GRPR). Biokinetic studies and micro-SPECT/CT images were obtained using athymic mice with T47D induced tumors. Spectroscopic studies and HPLC analyses indicated that the conjugate was obtained with high chemical and radiochemical purity (98 ± 1.3%). T47D-tumors were clearly visible with high contrast at 2 h after radiopharmaceutical administration. The {sup 177}Lu-absorbed dose delivered to tumors was 23.9 ± 2.1 Gy (74 MBq, intravenously administered) {sup 177}Lu-Folate-Bn demonstrated properties suitable as a theranostic radiopharmaceutical for breast tumors expressing Fr s and GRPR s. (Author)

  10. Bombesin receptors and transplanted stem cells in rat brain: High-resolution scan with {sup 99m}Tc BN1.1

    Energy Technology Data Exchange (ETDEWEB)

    Scopinaro, F. [Department of Radiological Sciences, University ' La Sapienza' Rome (Italy)]. E-mail: francesco.scopinaro@uniroma1.it; Paschali, E. [NSC Demokritos, Athens (Greece); Di Santo, G. [Department of Radiological Sciences, University ' La Sapienza' Rome (Italy); Antonellis, T. [Department of Radiological Sciences, University ' La Sapienza' Rome (Italy); Massari, R. [Institute of Biomedical Engineering, ISIB-CNR, Rome-Li-tech srl, Lauzacco Pavia di Udine (UD) (Italy); Trotta, C. [Institute of Biomedical Engineering, ISIB-CNR, Rome-Li-tech srl, Lauzacco Pavia di Udine (UD) (Italy); Gourni, H. [NSC Demokritos, Athens (Greece); Bouziotis, P. [NSC Demokritos, Athens (Greece); David, V. [Department of Radiological Sciences, University ' La Sapienza' Rome (Italy); Soluri, A. [Institute of Biomedical Engineering, ISIB-CNR, Rome-Li-tech srl, Lauzacco Pavia di Udine (UD) (Italy); Varvarigou, A.D. [NSC Demokritos, Athens (Greece)

    2006-12-20

    The aim of this work is to detect the presence of transplanted stem cells (TSC) in rat brain with high-resolution (HR) scintigraphy and labelled bombesin (BN). BN is a morphogen for Central Nervous System (CNS) as well as for other organs: CNS-oriented TSC over-express BN Receptors (BNR). BN is also a neurotransmitter and modulates several functions of CNS. {sup 99m}Tc labelled BN-like peptide scan of CNS is the ideal method to detect growing TSC once knowing normal distribution of BNRs in CNS. HR Planar and single photon emission computerized tomography (SPECT) images of rat brain were performed with new HR detectors (Li-tech, Italy). Pertechnetate, {sup 99m}Tc HMPAO and the new {sup 99m}Tc BN1.1 (patented) were i.v. administered in five rats. HR SPECT of {sup 99m}Tc BN1.1 detected olfactory tract, fronto-lateral cortex, cerebellum, basal ganglia and amygdale. Results of SPECT were confirmed by bio-distribution study performed after autopsy of three of the five rats. The remaining two rats underwent cerebral lesions followed by transplant of TSC. Three months later, HR scintigraphy was repeated and showed images completely different from previous basal study, with hot spot of {sup 99m}Tc BN1.1 corresponding to the site of TSC transplant. Immuno-histochemistry confirmed the presence of viable TSC. Not only {sup 99m}Tc BN1.1 HR scan showed viability of transplanted TSC but also the 'background brain' was the still now unknown map of BNR in mammalian brain.

  11. Bombesin receptors and transplanted stem cells in rat brain: High-resolution scan with 99mTc BN1.1

    Science.gov (United States)

    Scopinaro, F.; Paschali, E.; Di Santo, G.; Antonellis, T.; Massari, R.; Trotta, C.; Gourni, H.; Bouziotis, P.; David, V.; Soluri, A.; Varvarigou, A. D.

    2006-12-01

    The aim of this work is to detect the presence of transplanted stem cells (TSC) in rat brain with high-resolution (HR) scintigraphy and labelled bombesin (BN). BN is a morphogen for Central Nervous System (CNS) as well as for other organs: CNS-oriented TSC over-express BN Receptors (BNR). BN is also a neurotransmitter and modulates several functions of CNS. 99mTc labelled BN-like peptide scan of CNS is the ideal method to detect growing TSC once knowing normal distribution of BNRs in CNS. HR Planar and single photon emission computerized tomography (SPECT) images of rat brain were performed with new HR detectors (Li-tech, Italy). Pertechnetate, 99mTc HMPAO and the new 99mTc BN1.1 (patented) were i.v. administered in five rats. HR SPECT of 99mTc BN1.1 detected olfactory tract, fronto-lateral cortex, cerebellum, basal ganglia and amygdale. Results of SPECT were confirmed by bio-distribution study performed after autopsy of three of the five rats. The remaining two rats underwent cerebral lesions followed by transplant of TSC. Three months later, HR scintigraphy was repeated and showed images completely different from previous basal study, with hot spot of 99mTc BN1.1 corresponding to the site of TSC transplant. Immuno-histochemistry confirmed the presence of viable TSC. Not only 99mTc BN1.1 HR scan showed viability of transplanted TSC but also the "background brain" was the still now unknown map of BNR in mammalian brain.

  12. Bombesin receptors and transplanted stem cells in rat brain: High-resolution scan with 99mTc BN1.1

    International Nuclear Information System (INIS)

    The aim of this work is to detect the presence of transplanted stem cells (TSC) in rat brain with high-resolution (HR) scintigraphy and labelled bombesin (BN). BN is a morphogen for Central Nervous System (CNS) as well as for other organs: CNS-oriented TSC over-express BN Receptors (BNR). BN is also a neurotransmitter and modulates several functions of CNS. 99mTc labelled BN-like peptide scan of CNS is the ideal method to detect growing TSC once knowing normal distribution of BNRs in CNS. HR Planar and single photon emission computerized tomography (SPECT) images of rat brain were performed with new HR detectors (Li-tech, Italy). Pertechnetate, 99mTc HMPAO and the new 99mTc BN1.1 (patented) were i.v. administered in five rats. HR SPECT of 99mTc BN1.1 detected olfactory tract, fronto-lateral cortex, cerebellum, basal ganglia and amygdale. Results of SPECT were confirmed by bio-distribution study performed after autopsy of three of the five rats. The remaining two rats underwent cerebral lesions followed by transplant of TSC. Three months later, HR scintigraphy was repeated and showed images completely different from previous basal study, with hot spot of 99mTc BN1.1 corresponding to the site of TSC transplant. Immuno-histochemistry confirmed the presence of viable TSC. Not only 99mTc BN1.1 HR scan showed viability of transplanted TSC but also the 'background brain' was the still now unknown map of BNR in mammalian brain

  13. Study of the optical and dosimetric properties of the nano conjugate {sup 99m}Tc-EDDA/HYNIC-GGC-Au Np-Bombesin by effect of nano particle size; Estudio de las propiedades opticas y dosimetricas del nanoconjugado {sup 99m}Tc-EDDA/HYNIC-GGC-AUNP-Bombesina por efecto del tamano de nanoparticula

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza S, A. N.

    2011-07-01

    The receptors over-expressed on the surface of cancer cells represent promising targets for breast cancer diagnosis or therapy. The gastrin-releasing peptide receptor (GRP-r) is a seven-transmembrane G-protein coupled receptor that is over-expressed on primary prostate and breast cancer and lymph node metastases. Bombesin (Bn) is a tetradeca peptide that binds with high affinity to GRP-r. The strong, specific Bn-GRP-r binding is the basis for labelling Bn with radionuclides (i.e. {sup 99m}Tc, {sup 111}In, {sup 18}F) to obtain molecular images. The aim of this work was to develop 3 multifunctional systems of {sup 99m}Tc-labeled gold nanoparticles (Au Np) (5, 10 and 20 nm) conjugated to Lys{sup 3}-Bombesin for GRP-receptor targeting in breast cancer. The systems were characterized by Tem and UV-Vis, IR, Raman, Fluorescence and XP spectroscopy. The {sup 99m}Tc-Au Np-Lys{sup 3}-Bombesin multifunctional system (20 nm) shows in vitro and in vivo specific recognition for GRP-r and suitable properties to be used as a nuclear molecular imaging agent. Results also showed a specific Lys{sup 3}-Bombesin binding to the gold surface and higher fluorescence intensity for the 20 nm system. The Nir bands observed in the 20 nm radio conjugate indicate potential for bio imaging as dual systems. (Author)

  14. Early events elicited by bombesin and structurally related peptides in quiescent Swiss 3T3 cells. II. Changes in Na/sup +/ and Ca/sup 2 +/ fluxes, Na/sup +//K/sup +/ pump activity, and intracellular pH

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, S.A.; Schneider, J.A.; Lopez-Rivas, A.; Sinnett-Smith, J.W.; Rozengurt, E.

    1986-06-01

    The amphibian tetradecapeptide, bombesin, and structurally related peptides caused a marked increase in ouabain-sensitive /sup 86/Rb/sup +/ uptake (a measure of Na/sup +//K/sup +/ pump activity) in quiescent Swiss 3T3 cells. This effect occurred within seconds after the addition of the peptide and appeared to be mediated by an increase in Na/sup +/ entry into the cells. The effect of bombesin on Na/sup +/ entry and Na/sup +//K/sup +/ pump activity was concentration dependent with half-maximal stimulation occurring at 0.3-0.4 nM. The structurally related peptides litorin, gastrin-releasing peptide, and neuromedin B also stimulated ouabain-sensitive /sup 86/Rb/sup +/ uptake; the relative potencies of these peptides in stimulating the Na/sup +//K/sup +/ pump were comparable to their potencies in increasing DNA synthesis. Bombesin increased Na/sup +/ influx, at least in part, through an Na/sup +//H/sup +/ antiport. The peptide augmented intracellular pH and this effect was abolished in the absence of extracellular Na/sup +/. In addition to monovalent ion transport, bombesin and the structurally related peptides rapidly increased the efflux of /sup 45/Ca/sup 2 +/ from quiescent Swiss 3T3 cells. This Ca/sup 2 +/ came from an intracellular pool and the efflux was associated with a 50% decrease in total intracellular Ca/sup 2 +/. The peptides also caused a rapid increase in cytosolic free calcium concentration. Prolonged pretreatment of Swiss 3T3 cells with phorbol dibutyrate, which causes a loss of protein kinase C activity, greatly decreased the stimulation of /sup 86/Rb/sup +/ uptake and Na/sup +/ entry by bombesin implicating this phosphotransferase system in the mediation of part of these responses to bombesin. Since some activation of monovalent ion transport by bombesin was seen in phorbol dibutyrate-pretreated cells, it is likely that the peptide also stimulates monovalent ion transport by a second mechanism.

  15. The Effect of Mini-PEG-Based Spacer Length on Binding and Pharmacokinetic Properties of a 68Ga-Labeled NOTA-Conjugated Antagonistic Analog of Bombesin

    Directory of Open Access Journals (Sweden)

    Zohreh Varasteh

    2014-07-01

    Full Text Available The overexpression of gastrin-releasing peptide receptor (GRPR in cancer can be used for peptide-receptor mediated radionuclide imaging and therapy. We have previously shown that an antagonist analog of bombesin RM26 conjugated to 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA via a diethyleneglycol (PEG2 spacer (NOTA-PEG2-RM26 and labeled with 68Ga can be used for imaging of GRPR-expressing tumors. In this study, we evaluated if a variation of mini-PEG spacer length can be used for optimization of targeting properties of the NOTA-conjugated RM26. A series of analogs with different PEG-length (n = 2, 3, 4, 6 was synthesized, radiolabeled and evaluated in vitro and in vivo. The IC50 values of natGa-NOTA-PEGn-RM26 (n = 2, 3, 4, 6 were 3.1 ± 0.2, 3.9 ± 0.3, 5.4 ± 0.4 and 5.8 ± 0.3 nM, respectively. In normal mice all conjugates demonstrated similar biodistribution pattern, however 68Ga-NOTA-PEG3-RM26 showed lower liver uptake. Biodistribution of 68Ga-NOTA-PEG3-RM26 was evaluated in nude mice bearing PC-3 (prostate cancer and BT-474 (breast cancer xenografts. High uptake in tumors (4.6 ± 0.6%ID/g and 2.8 ± 0.4%ID/g for PC-3 and BT-474 xenografts, respectively and high tumor-to-background ratios (tumor/blood of 44 ± 12 and 42 ± 5 for PC-3 and BT-474 xenografts, respectively were found already at 2 h p.i. of 68Ga-NOTA-PEG3-RM26. Results of this study suggest that variation in the length of the PEG spacer can be used for optimization of targeting properties of peptide-chelator conjugates. However, the influence of the mini-PEG length on biodistribution is minor when di-, tri-, tetra- and hexaethylene glycol are compared.

  16. In vitro and in vivo evaluation of a (18F-labeled high affinity NOTA conjugated bombesin antagonist as a PET ligand for GRPR-targeted tumor imaging.

    Directory of Open Access Journals (Sweden)

    Zohreh Varasteh

    Full Text Available Expression of the gastrin-releasing peptide receptor (GRPR in prostate cancer suggests that this receptor can be used as a potential molecular target to visualize and treat these tumors. We have previously investigated an antagonist analog of bombesin (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26 conjugated to 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA via a diethylene glycol (PEG2 spacer (NOTA-P2-RM26 labeled with (68Ga and (111In. We found that this conjugate has favorable properties for in vivo imaging of GRPR-expression. The focus of this study was to develop a (18F-labelled PET agent to visualize GRPR. NOTA-P2-RM26 was labeled with (18F using aluminum-fluoride chelation. Stability, in vitro binding specificity and cellular processing tests were performed. The inhibition efficiency (IC50 of the [(natF]AlF-NOTA-P2-RM26 was compared to that of the (natGa-loaded peptide using (125I-Tyr(4-BBN as the displacement radioligand. The pharmacokinetics and in vivo binding specificity of the compound were studied. NOTA-P2-RM26 was labeled with (18F within 1 h (60-65% decay corrected radiochemical yield, 55 GBq/µmol. The radiopeptide was stable in murine serum and showed high specific binding to PC-3 cells. [(natF]AlF-NOTA-P2-RM26 showed a low nanomolar inhibition efficiency (IC50=4.4±0.8 nM. The internalization rate of the tracer was low. Less than 14% of the cell-bound radioactivity was internalized after 4 h. The biodistribution of [(18F]AlF-NOTA-P2-RM26 demonstrated rapid blood clearance, low liver uptake and low kidney retention. The tumor uptake at 3 h p.i. was 5.5±0.7 %ID/g, and the tumor-to-blood, -muscle and -bone ratios were 87±42, 159±47, 38±16, respectively. The uptake in tumors, pancreas and other GRPR-expressing organs was significantly reduced when excess amount of non-labeled peptide was co-injected. The low uptake in bone suggests a high in vivo stability of the Al-F bond. High contrast PET image was obtained 3 h p

  17. Optimization of the production process of hybrid and multivalent formulation Bombesin/RGD for the opportune detection of breast cancer; Optimizacion del proceso de fabricacion de la formulacion hibrida y multivalente Bombesina/RGD para la deteccion oportuna de cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Robles M, M.

    2013-07-01

    The radiopharmaceuticals of third generation are used in nuclear medicine to obtain images of specific molecular targets, and they are unique in their capacity to detect in vivo specific biochemical sites as receptors that are over-expressed in diverse illness. In cancer cells several types of receptors are over-expressed, as the integrin s α(v)β(3) and α(v)β(5) that specifically recognize the sequence RGD (Arginine-Glycin-Ac. Aspartic) and gastrin-releasing peptide that recognizes specifically to the peptide Lys{sup 3}-Bombesin. The integrin s α(v)β(3) and α(v)β(5) are involved in the tumor angio genesis processes and the gastrin-releasing peptide is over-expressed in breast and prostate cancer. The molecular recognition of the specific receptors is the basis to be utilized as targets of the radiopharmaceuticals {sup 99m}Tc-HYNIC-Bombesin and {sup 99m}Tc-HYNIC-RGD. In this work was developed a lyophilized pharmaceutical formulation effective, stable and safe for the simultaneous obtaining of the radiopharmaceuticals {sup 99m}Tc-HYNIC-Bombesin ({sup 99m}Tc-EDDA/HYNIC-Lys{sup 3}-Bombesin) and {sup 99m}Tc-HYNIC-RGD ({sup 99m}Tc EDDA/HYNIC-E-[c(RGDfK)]{sub 2}). Later on the production process of the product HYNIC-Bombesin/RGD-Sn was optimized using a factorial design and the formulation was transferred to the production plant of radiopharmaceuticals of the Instituto Nacional de Investigaciones Nucleares (ININ). The optimized formulation is described in the following chart: HYNIC-[Lys{sup 3}]-Bombesin - 12.5 μg; HYNIC-E-c[RGDfK]{sub 2} - 12.5 μg; Stannous chloride (SnCl{sub 2}) - 20 μg; Ethylenediamine diacetic acid (EDDA) - 10 mg; N-tris(hydroxymethyl)methyl glycin (Tricine) - 20 mg; Mannitol - 50 mg. The production process was validated and were carried out the stability studies under refrigeration conditions. (Author)

  18. Imaging small human prostate cancer xenografts after pretargeting with bispecific bombesin-antibody complexes and targeting with high specific radioactivity labeled polymer-drug conjugates

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Vishwesh; Gada, Keyur; Panwar, Rajiv; Ferris, Craig; Khaw, Ban-An [Northeastern University, School of Pharmacy, Department of Pharmaceutical Sciences, Boston, MA (United States); Varvarigou, Alexandra [Institute of Radioisotopes and Radiodiagnostics, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Majewski, Stan [West Virginia University, Department of Radiology, Nuclear Medicine Imaging Instrumentation Program, Center for Advanced Imaging, Morgantown, WV (United States); Weisenberger, Andrew [Jefferson LA, Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tekabe, Yared [Columbia University Medical Center, New York, NY (United States)

    2012-05-15

    Pretargeting with bispecific monoclonal antibodies (bsMAb) for tumor imaging was developed to enhance target to background activity ratios. Visualization of tumors was achieved by the delivery of mono- and divalent radiolabeled haptens. To improve the ability to image tumors with bsMAb, we have combined the pretargeting approach with targeting of high specific activity radiotracer labeled negatively charged polymers. The tumor antigen-specific antibody was replaced with bombesin (Bom), a ligand that binds specifically to the growth receptors that are overexpressed by many tumors including prostate cancer. Bom-anti-diethylenetriaminepentaacetic acid (DTPA) bispecific antibody complexes were used to demonstrate pretargeting and imaging of very small human prostate cancer xenografts targeted with high specific activity {sup 111}In- or {sup 99m}Tc-labeled negatively charged polymers. Bispecific antibody complexes consisting of intact anti-DTPA antibody or Fab' linked to Bom via thioether bonds (Bom-bsCx or Bom-bsFCx, respectively) were used to pretarget PC-3 human prostate cancer xenografts in SCID mice. Negative control mice were pretargeted with Bom or anti-DTPA Ab. {sup 111}In-Labeled DTPA-succinyl polylysine (DSPL) was injected intravenously at 24 h (7.03 {+-} 1.74 or 6.88 {+-} 1.89 MBq {sup 111}In-DSPL) after Bom-bsCx or 50 {+-} 5.34 MBq of {sup 99m}Tc-DSPL after Bom-bsFCx pretargeting, respectively. Planar or single photon emission computed tomography (SPECT)/CT gamma images were obtained for up to 3 h and only planar images at 24 h. After imaging, all mice were killed and biodistribution of {sup 111}In or {sup 99m}Tc activities were determined by scintillation counting. Both planar and SPECT/CT imaging enabled detection of PC-3 prostate cancer lesions less than 1-2 mm in diameter in 1-3 h post {sup 111}In-DSPL injection. No lesions were visualized in Bom or anti-DTPA Ab pretargeted controls. {sup 111}In-DSPL activity in Bom-bsCx pretargeted tumors (1

  19. Comparative study on DOTA-derivatized bombesin analog labeled with 90Y and 177Lu: in vitro and in vivo evaluation

    International Nuclear Information System (INIS)

    Introduction: The aim of the study was to compare in vitro and in vivo a novel DOTA-chelated bombesin (BN) analog of the amino acid sequence, QRLGNQWAVGHLM-CONH2 (BN[2-14]NH2), labeled with 90Y and 177Lu, for its potential use in targeted radiotherapy of tumors expressing gastrin releasing peptide (GRP) receptors. The same amino acid sequence, but with different chelator, referred as BN1.1 (Gly-Gly-Cys-Aca-QRLGNQWAVGHLM-CONH2), has already been studied and reported; however, the DOTA-chelated one, suitable for labeling with M+3 type radiometals, was not yet described. Methods: The conditions for labeling of DOTA-BN[2-14]NH2 with noncarrier added 90Y and with 177Lu [specific activity (SA), 15 Ci/mg Lu] were investigated and optimized to provide 90Y-DOTA-BN[2-14]NH2 and 177Lu-DOTA-BN[2-14]NH2 of high SA. The stability of the radiolabeled compounds in human serum was evaluated over a period of 24 h. The human prostate cancer cell line PC-3, known to express GRP receptors, was used for in vitro evaluation of radiolabeled peptide affinity to GRP receptors and for assessment of cytotoxicity of both nonlabeled and radiolabeled peptide. Biodistribution accompanied by receptor blocking was studied in normal Swiss mice. Results: 90Y-DOTA-BN[2-14]NH2 and 177Lu-DOTA-BN[2-14]NH2 were obtained with radiochemical yield >98% and high SA (67.3 GBq 90Y/μmol and 33.6 GBq 177Lu/μmol, respectively). They were stable when incubated in human serum for up to 24 h. The binding affinities of DOTA-BN[2-14]NH2 and both natY- and natLu-labeled analogs to GRP receptors were high (IC50=1.78, 1.99, and 1.34 nM, respectively), especially for the natLu-DOTA-BN[2-14]NH2 complex. The cytotoxicity study of DOTA-BN[2-14]NH2 to PC-3 cells revealed an IC50=6300 nM after 72 h of exposition, while the labeled derivatives showed no significant cytotoxic effect. The internalization rate to PC-3 cells was more rapid for 177Lu-labeled peptide (84.87%) than for the 90Y-labeled one (80.79%), while the efflux

  20. Biokinetics and dosimetry in patients of {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesin: images of GRP receptors; Biocinetica y dosimetria en humanos de {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesina: imagenes de receptores GRP

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C. L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2007-07-01

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [{sup 99m}Tc]EDDA/HYNIC-Lys{sup 3}-bombesin ({sup 99m}Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red

  1. In vitro and in vivo evaluation of Alexa Fluor 680-bombesin[7-14]NH2 peptide conjugate, a high-affinity fluorescent probe with high selectivity for the gastrin-releasing peptide receptor.

    Science.gov (United States)

    Ma, Lixin; Yu, Ping; Veerendra, Bhadrasetty; Rold, Tammy L; Retzloff, Lauren; Prasanphanich, Adam; Sieckman, Gary; Hoffman, Timothy J; Volkert, Wynn A; Smith, Charles J

    2007-01-01

    Gastrin-releasing peptide (GRP) receptors are overexpressed on several types of human cancer cells, including breast, prostate, small cell lung, and pancreatic cancers. Bombesin (BBN), a 14-amino acid peptide that is an analogue of human GRP, binds to GRP receptors with very high affinity and specificity. The aim of this study was to develop a new fluorescent probe based on BBN having high tumor uptake and optimal pharmacokinetics for specific targeting and optical imaging of human breast cancer tissue. In this study, solid-phase peptide synthesis was used to produce H(2)N-glycylglycylglycine-BBN[7-14]NH(2) peptide with the following general sequence: H(2)N-G-G-G-Q-W-A-V-G-H-L-M-(NH(2)). This conjugate was purified by reversed-phase high-performance liquid chromatography and characterized by electrospray-ionization mass spectra. The fluorescent probe Alexa Fluor 680-G-G-G-BBN[7-14]NH(2) conjugate was prepared by reaction of Alexa Fluor 680 succinimidyl ester to H(2)N-G-G-G-BBN[7-14]NH(2) in dimethylformamide (DMF). In vitro competitive binding assays, using (125)I-Tyr(4)-BBN as the radiolabeling gold standard, demonstrated an inhibitory concentration 50% value of 7.7 +/- 1.4 nM in human T-47D breast cancer cells. Confocal fluorescence microscopy images of Alexa Fluor 680-G-G-G-BBN[7-14]NH(2) in human T-47D breast cancer cells indicated specific uptake, internalization, and receptor blocking of the fluorescent bioprobe in vitro. In vivo investigations in SCID mice bearing xenografted T-47D breast cancer lesions demonstrated the ability of this new conjugate to specifically target tumor tissue with high selectivity and affinity.

  2. Optimization, biological evaluation and microPET imaging of copper-64-labeled bombesin agonists, [{sup 64}Cu-NO2A-(X)-BBN(7-14)NH{sub 2}], in a prostate tumor xenografted mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Stephanie R., E-mail: srlf36@mail.missouri.ed [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211 (United States); Nanda, Prasanta [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Rold, Tammy L. [Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Sieckman, Gary L. [Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); Figueroa, Said D. [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); Hoffman, Timothy J. [Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); The Radiopharmaceutical Sciences Institute, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211 (United States); Jurisson, Silvia S. [Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211 (United States); Smith, Charles J., E-mail: smithcj@health.missouri.ed [Department of Radiology, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States); Research Division, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO 65201 (United States); University of Missouri Research Reactor Center, University of Missouri-Columbia, Columbia, MO 65211 (United States); The Radiopharmaceutical Sciences Institute, University of Missouri-Columbia School of Medicine, Columbia, MO 65211 (United States)

    2010-10-15

    Gastrin-releasing peptide receptors (GRPr) are a member of the bombesin (BBN) receptor family. GRPr are expressed in high numbers on specific human cancers, including human prostate cancer. Therefore, copper-64 ({sup 64}Cu) radiolabeled BBN(7-14)NH{sub 2} conjugates could have potential for diagnosis of human prostate cancer via positron-emission tomography (PET). The aim of this study was to produce [{sup 64}Cu-NO2A-(X)-BBN(7-14)NH{sub 2}] conjugates for prostate cancer imaging, where X=pharmacokinetic modifier (beta-alanine, 5-aminovaleric acid, 6-aminohexanoic acid, 8-aminooctanoic acid, 9-aminonanoic acid or para-aminobenzoic acid) and NO2A=1,4,7-triazacyclononane-1,4-diacetic acid [a derivative of NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid)]. Methods: [(X)-BBN(7-14)NH{sub 2}] Conjugates were synthesized by solid-phase peptide synthesis (SPPS), after which NOTA was added via manual conjugation. The new peptide conjugates were radiolabeled with {sup 64}Cu radionuclide. The receptor-binding affinity was determined in human prostate PC-3 cells, and tumor-targeting efficacy was determined in PC-3 tumor-bearing severely combined immunodeficient (SCID) mice. Whole-body maximum intensity microPET/CT images of PC-3 tumor-bearing SCID mice were obtained 18 h postinjection (pi). Results: Competitive binding assays in PC-3 cells indicated high receptor-binding affinity for the [NO2A-(X)-BBN(7-14)NH{sub 2}] and [{sup nat}Cu-NO2A-(X)-BBN(7-14)NH{sub 2}] conjugates. In vivo biodistribution studies of the [{sup 64}Cu-NO2A-(X)-BBN(7-14)NH{sub 2}] conjugates at 1, 4 and 24 h pi showed very high uptake of the tracer in GRPr-positive tissue with little accumulation and retention in nontarget tissues. High-quality, high-contrast microPET images were obtained, with xenografted tumors being clearly visible at 18 h pi. Conclusions: NO2A chelator sufficiently stabilizes copper(II) radiometal under in vivo conditions, producing conjugates with very high uptake and retention in

  3. Optimization, biological evaluation and microPET imaging of copper-64-labeled bombesin agonists, [64Cu-NO2A-(X)-BBN(7-14)NH2], in a prostate tumor xenografted mouse model

    International Nuclear Information System (INIS)

    Gastrin-releasing peptide receptors (GRPr) are a member of the bombesin (BBN) receptor family. GRPr are expressed in high numbers on specific human cancers, including human prostate cancer. Therefore, copper-64 (64Cu) radiolabeled BBN(7-14)NH2 conjugates could have potential for diagnosis of human prostate cancer via positron-emission tomography (PET). The aim of this study was to produce [64Cu-NO2A-(X)-BBN(7-14)NH2] conjugates for prostate cancer imaging, where X=pharmacokinetic modifier (beta-alanine, 5-aminovaleric acid, 6-aminohexanoic acid, 8-aminooctanoic acid, 9-aminonanoic acid or para-aminobenzoic acid) and NO2A=1,4,7-triazacyclononane-1,4-diacetic acid [a derivative of NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid)]. Methods: [(X)-BBN(7-14)NH2] Conjugates were synthesized by solid-phase peptide synthesis (SPPS), after which NOTA was added via manual conjugation. The new peptide conjugates were radiolabeled with 64Cu radionuclide. The receptor-binding affinity was determined in human prostate PC-3 cells, and tumor-targeting efficacy was determined in PC-3 tumor-bearing severely combined immunodeficient (SCID) mice. Whole-body maximum intensity microPET/CT images of PC-3 tumor-bearing SCID mice were obtained 18 h postinjection (pi). Results: Competitive binding assays in PC-3 cells indicated high receptor-binding affinity for the [NO2A-(X)-BBN(7-14)NH2] and [natCu-NO2A-(X)-BBN(7-14)NH2] conjugates. In vivo biodistribution studies of the [64Cu-NO2A-(X)-BBN(7-14)NH2] conjugates at 1, 4 and 24 h pi showed very high uptake of the tracer in GRPr-positive tissue with little accumulation and retention in nontarget tissues. High-quality, high-contrast microPET images were obtained, with xenografted tumors being clearly visible at 18 h pi. Conclusions: NO2A chelator sufficiently stabilizes copper(II) radiometal under in vivo conditions, producing conjugates with very high uptake and retention in targeted GRPr. Preclinical evaluation of these new peptide

  4. 蛙皮素样肽调控胰岛素分泌机制研究进展%Progress on Regulatory Mechanisms of Bombesin-like Peptides on Insulin Secretion

    Institute of Scientific and Technical Information of China (English)

    赵红琼; 姚刚; 夏利宁

    2016-01-01

    Mammalian bombesin-like peptides (BLPs)include gastrin-releasing peptide (GRP),neurome-din C (NMC)and neuromedin B (NMB).Two main receptor subtypes,the GRP-receptor and the NMB-receptor,mediate the biological functions of BLPs.BLPs and their receptors histologically localize in the pancreas.BLPs have been reported to stimulate the secretion of insulin mediated by the GRP-receptor.The efficiency of BLP on insulin secretion is affected by animal species,blood glucose level and energy level. BLPs may act as a neurotransmitter to directly stimulate pancreatic isletβ-cells,or indirectly activate the parasympathetic neuron to increase the secretion of insulin.Moreover,BLPs may activate the inositol triphosphate and promote the secretion of insulin when the cytosolic Ca2 + concentration increased through promoting extracellular Ca2 + influx and mobilization of intracellular calcium stores.The inositol triphos-phate pathway may mediate the BLPs-induced insulin secretion.Studies of BLPs on insulin secretion not only complement the theoretical mechanism of regulation of insulin secretion,but also provide a novel idea for clinical treatment of diabetes.%哺乳动物蛙皮素样肽(BLP)主要包括胃泌素释放肽(GRP)、神经肽 C(NMC)和神经肽 B (NMB),主要通过 GRP-R 和 NMB-R 2种受体亚型介导生物学效应。其受体 BRS-3的内源性配体尚未发现。BLP 已经被证明具有促进胰岛素分泌的作用。从组织定位来看,BLP 及其受体在胰腺均有分布,其调控胰岛素的分泌主要通过 GRP-R 介导,其效能与动物的种属、血糖和能量水平有关。BLP 可能作为胰腺内神经递质直接促进胰岛β细胞或间接通过激活副交感神经促进胰岛素分泌。BLP 还可激活三磷酸肌醇等途径,增加胞外 Ca2+内流或者动员胞内钙库,促进胰岛素分泌。BLP 对胰岛素分泌的研究不仅补充调控胰岛素分泌机制的理论,也为临床糖尿病的治疗提供新的思路。

  5. 乙酰胆碱、蛙皮素和P物质对人食管下括约肌张力调节的细胞内信号转导机制%The study on the intracellular signal transduction pathways in contraction of the human lower esophageal sphincter induced by acetylcholine, bombesin and substance P

    Institute of Scientific and Technical Information of China (English)

    王岩; 刘俊峰; 张鑫; 高庆敏

    2010-01-01

    Objective To investigate the roles of two distinct intracellular signal transduction pathways:Protein Kinase C (PKC)-dependent and calmodulin-dependent, in the contractile mechanism of the clasp and sling fibers, the two parts of human lower esophageal sphincter, in comparison with circular muscle from gastric fundus and esophagus. Meanwhile the roles of extracellular and intracellular Ca2+ in this process were studied. Methods ( 1 ) Cells from the clasp fiber,the sling fiber,the circular muscles of the esophagus and the gastric fundus were contracted by exposure to acetylcholine, bombesin and substance P. (2) When Protein Kinase C (PKC)-dependent pathway inhibitors H7, calmodulin-dependent pathway inhibitor CGS9343B,Ca2 + -free medium or substitution of 4 mmol/L Sr2 + for Ca2 + were used, the cells were incubated in appropriate solution for 5 min before addition of agonists. The length of each cell was measured by video-based motion edge-detection system. Results Maximal contraction of the cells of the clasp fibers was blocked by H7 (5 ± 1 ) %, (5 ± 2 ) % , (6 ± 2 ) % and by incubation in Ca2+ -free medium (4 ± 1 ) % ,(6 ± 1 )%, (3 ±1 )% , but not by the CGS9343B and 4mmol/L Sr2 +. By contrast, Maximal contraction of the cells from sling fibers was blocked only by CGS9343 B ( 3 ± 1 ) %、 (4 ± 2 ) %, ( 6 ± 1 ) % and 4 mmol/L Sr2+ (5 ± 2) %, (3 ± 1 ) %, (6 ± 2 ) %. Conclusion Contraction of the sling fibers and the circular muscle of the gastric fundus depends on release of intracellular calcium and activation of a calmodulin-dependent pathway. While contraction of the clasp fibers and the circular muscle of the esophagus depends on influx of extracellular calcium and activation of a PKC-dependent signal transduction pathway.%目的 观察蛋白激酶C(PKC)和钙调蛋白信号转导通路在乙酰胆碱、蛙皮素和P物质对人食管下括约肌钩状纤维和套索纤维张力调节中的作用.方法 应用PKC信号通路特异性阻断剂H7和

  6. Localization of receptors for bombesin-like peptides in the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Moody, T.W.; Getz, R.; O' Donohue, T.L.; Rosenstein, J.M.

    1988-01-01

    BN-like peptides and receptors are present in discrete areas of the mammalian brain. By radioimmunoassay, endogenous BN/GRP, neuromedin B, and ranatensin-like peptides are present in the rat brain. High-to-moderate concentrations of BN/GRP are present in the rat hypothalamus and thalamus, whereas moderate-to-high densities of neuromedin B and ranatensin-like peptides are present in the olfactory bulb and hippocampus, as well as in the hypothalamus and thalamus. While the distribution of neuromedin B and ranatensin-like peptides appears similar, it is distinct from that of BN/GRP. When released from CNS neurons, these peptides may interact with receptors for BN-like peptides. BN, GRP, ranatensin, and neuromedin B inhibit specific (/sup 125/I-Tyr4)BN binding with high affinity. By use of in vitro autoradiographic techniques to detect binding of (/sup 125/I-Tyr4)BN to receptors for BN-like peptides, high grain densities were found in the olfactory bulb and tubercle, the nucleus accumbens, the suprachiasmatic and paraventricular nucleus of the hypothalamus, the central medial and paraventricular thalamic nuclei, the hippocampus, the dentate gyrus, and the amygdala of the rat brain. Some of these receptors may be biologically active and mediate the biological effects of BN-like peptides. For example, when BN is directly injected into the nucleus accumbens, pronounced grooming results and the effects caused by BN are reversed by spantide and (D-Phe12)BN. Thus, the putative BN receptor antagonists may serve as useful agents to investigate the biological significance of BN-like peptides in the CNS.

  7. Preclinical Evaluation of a Novel In-111-Labeled Bombesin Homodimer for Improved Imaging of GRPR-Positive Prostate Cancer

    NARCIS (Netherlands)

    Carlucci, G.; Ananias, H. J. K.; Yu, Z.; Hoving, H. D.; Helfrich, W.; Dierckx, R. A. J. O.; Liu, S.; de Jong, I. J.; Elsinga, P. H.

    2013-01-01

    Rational-designed multimerization of targeting ligands can be used to improve kinetic and thermodynamic properties. Multimeric targeting ligands may be produced by tethering multiple identical or two or more monomeric ligands of different binding specificities. Consequently, multimeric ligands may s

  8. Gene : CBRC-MMUS-20-0026 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUS-20-0026 X A Bombesin receptors BRS3_MOUSE 0.0 100% ref|NP_033896.2| bombesin-like receptor 3 [Mus... musculus] sp|O54798|BRS3_MOUSE Bombesin receptor subtype-3 (BRS-3) dbj|BAA24404.1| ...bombesin receptor subtype-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI0696...3.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus...] emb|CAM25500.1| bombesin-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus

  9. Synthesis and biological evaluation of novel imidazol-1-ylacetic acid derivatives as non-brain penetrant bombesin receptor subtype-3 (BRS-3) agonists.

    Science.gov (United States)

    Kiyotsuka, Yohei; Shimada, Kousei; Kobayashi, Shozo; Suzuki, Masanori; Akiu, Mayuko; Asano, Masayoshi; Sogawa, Yoshitaka; Hara, Takashi; Konishi, Masahiro; Abe-Ohya, Rie; Izumi, Masanori; Nagai, Yoko; Yoshida, Kazuhiro; Abe, Yasuyuki; Takamori, Hideo; Takahashi, Hisashi

    2016-09-01

    Novel compounds based on 1a were synthesized with the focus of obtaining agonists acting upon peripheral BRS-3. To identify potent anti-obesity compounds without adverse effects on the central nervous system (CNS), a carboxylic acid moiety and a labile carboxylic ester with an antedrug functionality were introduced. Through the extensive synthetic exploration and the pharmacokinetic studies of intravenous administration in mice, the ester 2b was selected owing to its most suitable pharmacological profile. In the evaluation of food intake suppression in C57BL/6N mice, 2b showed significant in vivo efficacy and no clear adverse effects on blood pressure change in dogs administered the compound by intravenous infusion. PMID:27491709

  10. NCBI nr-aa BLAST: CBRC-MLUC-01-0302 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0302 ref|NP_001009215.1| bombesin receptor subtype 3 [Ovis aries] sp|O...97967|BRS3_SHEEP RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAD19639.1| bombesin receptor sub...type 3 [Ovis aries] gb|AAD19642.1| bombesin receptor subtype 3 [Ovis aries] NP_001009215.1 1e-110 84% ...

  11. NCBI nr-aa BLAST: CBRC-HSAP-23-0062 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-HSAP-23-0062 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 0.0 96% ...

  12. NCBI nr-aa BLAST: CBRC-EEUR-01-1457 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-EEUR-01-1457 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 1e-107 55% ...

  13. NCBI nr-aa BLAST: CBRC-OCUN-01-1277 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OCUN-01-1277 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 1e-70 95% ...

  14. NCBI nr-aa BLAST: CBRC-TBEL-01-1031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TBEL-01-1031 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 0.0 89% ...

  15. NCBI nr-aa BLAST: CBRC-XTRO-01-3530 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-XTRO-01-3530 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 1e-142 64% ...

  16. NCBI nr-aa BLAST: CBRC-GGAL-04-0014 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GGAL-04-0014 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 1e-156 68% ...

  17. NCBI nr-aa BLAST: CBRC-FCAT-01-0505 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FCAT-01-0505 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 1e-96 69% ...

  18. NCBI nr-aa BLAST: CBRC-RNOR-21-0248 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RNOR-21-0248 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 0.0 86% ...

  19. InterProScan Result: NM_001134240 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134240 NM_001134240_1_ORF2 8F7EFB5ECDE1E93B PANTHER PTHR19264:SF239 BOMBESIN ...RECEPTOR 6e-157 T IPR001556 Bombesin receptor Molecular Function: bombesin receptor activity (GO:0004946)|Bi

  20. NCBI nr-aa BLAST: CBRC-CFAM-39-0035 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CFAM-39-0035 ref|NP_001028074.1| bombesin-like receptor 3 [Macaca mulatta] sp|Q6H2Y3|BRS3_MACMU Bombes...in receptor subtype-3 (BRS-3) gb|AAR07972.1| bombesin-like receptor subtype 3 [Macaca mulatta] NP_001028074.1 0.0 88% ...

  1. InterProScan Result: NM_001134239 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134239 NM_001134239_3_ORF2 9C6209F61E5A8E68 PANTHER PTHR19264:SF239 BOMBESIN ...RECEPTOR 2.2e-147 T IPR001556 Bombesin receptor Molecular Function: bombesin receptor activity (GO:0004946)|

  2. NCBI nr-aa BLAST: CBRC-MMUS-20-0026 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUS-20-0026 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 85% ...

  3. NCBI nr-aa BLAST: CBRC-GGAL-04-0014 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GGAL-04-0014 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 1e-156 69% ...

  4. NCBI nr-aa BLAST: CBRC-OANA-01-2213 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OANA-01-2213 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 1e-149 66% ...

  5. NCBI nr-aa BLAST: CBRC-PABE-24-0058 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PABE-24-0058 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 99% ...

  6. NCBI nr-aa BLAST: CBRC-RMAC-21-0045 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RMAC-21-0045 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 96% ...

  7. NCBI nr-aa BLAST: CBRC-DNOV-01-2691 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-2691 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 2e-66 88% ...

  8. NCBI nr-aa BLAST: CBRC-PCAP-01-0612 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PCAP-01-0612 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  9. NCBI nr-aa BLAST: CBRC-MMUR-01-1435 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUR-01-1435 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  10. NCBI nr-aa BLAST: CBRC-TSYR-01-0977 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TSYR-01-0977 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  11. NCBI nr-aa BLAST: CBRC-HSAP-23-0062 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-HSAP-23-0062 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 100% ...

  12. NCBI nr-aa BLAST: CBRC-PVAM-01-1008 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PVAM-01-1008 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  13. NCBI nr-aa BLAST: CBRC-OPRI-01-0451 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-0451 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  14. NCBI nr-aa BLAST: CBRC-TBEL-01-1031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TBEL-01-1031 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 89% ...

  15. NCBI nr-aa BLAST: CBRC-FCAT-01-0505 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FCAT-01-0505 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 5e-99 70% ...

  16. NCBI nr-aa BLAST: CBRC-TTRU-01-0489 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0489 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  17. NCBI nr-aa BLAST: CBRC-CJAC-01-0931 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CJAC-01-0931 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 91% ...

  18. NCBI nr-aa BLAST: CBRC-RNOR-21-0248 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RNOR-21-0248 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 86% ...

  19. NCBI nr-aa BLAST: CBRC-OCUN-01-1277 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OCUN-01-1277 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 2e-71 95% ...

  20. NCBI nr-aa BLAST: CBRC-ACAR-01-0305 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0305 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 1e-138 62% ...

  1. NCBI nr-aa BLAST: CBRC-GGOR-01-0733 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GGOR-01-0733 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  2. NCBI nr-aa BLAST: CBRC-CPOR-01-1772 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CPOR-01-1772 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 86% ...

  3. NCBI nr-aa BLAST: CBRC-BTAU-01-1571 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-BTAU-01-1571 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 86% ...

  4. NCBI nr-aa BLAST: CBRC-MEUG-01-1671 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MEUG-01-1671 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  5. NCBI nr-aa BLAST: CBRC-TGUT-07-0000 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-07-0000 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 1e-149 67% ...

  6. NCBI nr-aa BLAST: CBRC-CFAM-39-0035 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CFAM-39-0035 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 89% ...

  7. NCBI nr-aa BLAST: CBRC-MLUC-01-0302 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0302 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  8. NCBI nr-aa BLAST: CBRC-PHAM-01-0161 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PHAM-01-0161 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  9. NCBI nr-aa BLAST: CBRC-STRI-01-2764 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-STRI-01-2764 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  10. NCBI nr-aa BLAST: CBRC-OGAR-01-1270 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OGAR-01-1270 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 1e-174 91% ...

  11. NCBI nr-aa BLAST: CBRC-PABE-01-0050 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PABE-01-0050 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 9.2 23% ...

  12. NCBI nr-aa BLAST: CBRC-PTRO-24-0043 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PTRO-24-0043 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P32247|BRS3_HUMAN Bombes...in receptor subtype-3 (BRS-3) gb|AAA35604.1| bombesin receptor subtype-3 emb|CAA54031.1| uterine bombes...in receptor [Homo sapiens] emb|CAB10731.1| bombesin-like receptor 3 [Homo sapiens] gb|AAT79496.1| bombes...in-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombesin-like receptor... 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic construct] NP_001718.1 0.0 99% ...

  13. NCBI nr-aa BLAST: CBRC-VPAC-01-1508 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-VPAC-01-1508 ref|NP_001718.1| bombesin-like receptor 3 [Homo sapiens] sp|P3224...7|BRS3_HUMAN RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 gb|AAA35604.1| bombesin receptor subtype...-3 [Homo sapiens] emb|CAA54031.1| uterine bombesin receptor [Homo sapiens] emb|CAB10731.1| bombesin-like rec...eptor 3 [Homo sapiens] gb|AAT79496.1| bombesin-like receptor 3 [Homo sapiens] gb|EAW88470.1| bombes...in-like receptor 3 [Homo sapiens] gb|AAI52939.1| Bombesin-like receptor 3 [synthetic const

  14. NCBI nr-aa BLAST: CBRC-MMUS-20-0026 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUS-20-0026 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 100% ...

  15. NCBI nr-aa BLAST: CBRC-PCAP-01-0612 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PCAP-01-0612 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 82% ...

  16. NCBI nr-aa BLAST: CBRC-MLUC-01-0302 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0302 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 1e-104 81% ...

  17. NCBI nr-aa BLAST: CBRC-DNOV-01-2691 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-2691 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 5e-65 86% ...

  18. NCBI nr-aa BLAST: CBRC-RMAC-21-0045 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RMAC-21-0045 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 85% ...

  19. NCBI nr-aa BLAST: CBRC-OPRI-01-0451 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-0451 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 84% ...

  20. NCBI nr-aa BLAST: CBRC-HSAP-23-0062 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-HSAP-23-0062 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 85% ...

  1. NCBI nr-aa BLAST: CBRC-PTRO-24-0043 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PTRO-24-0043 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 85% ...

  2. NCBI nr-aa BLAST: CBRC-OCUN-01-1277 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OCUN-01-1277 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 5e-70 93% ...

  3. NCBI nr-aa BLAST: CBRC-MMUR-01-1435 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUR-01-1435 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 87% ...

  4. NCBI nr-aa BLAST: CBRC-RNOR-21-0248 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RNOR-21-0248 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 96% ...

  5. NCBI nr-aa BLAST: CBRC-TSYR-01-0977 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TSYR-01-0977 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 85% ...

  6. NCBI nr-aa BLAST: CBRC-GGOR-01-0733 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GGOR-01-0733 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 2e-89 79% ...

  7. NCBI nr-aa BLAST: CBRC-OGAR-01-1270 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OGAR-01-1270 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 1e-169 89% ...

  8. NCBI nr-aa BLAST: CBRC-TBEL-01-1031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TBEL-01-1031 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 86% ...

  9. NCBI nr-aa BLAST: CBRC-EEUR-01-1457 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-EEUR-01-1457 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 1e-107 56% ...

  10. NCBI nr-aa BLAST: CBRC-CPOR-01-1772 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CPOR-01-1772 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 83% ...

  11. NCBI nr-aa BLAST: CBRC-PHAM-01-0161 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PHAM-01-0161 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 85% ...

  12. NCBI nr-aa BLAST: CBRC-STRI-01-2764 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-STRI-01-2764 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 87% ...

  13. NCBI nr-aa BLAST: CBRC-PVAM-01-1008 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PVAM-01-1008 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O5479...8|BRS3_MOUSE RecName: Full=Bombesin receptor subtype-3; Short=BRS-3 dbj|BAA24404.1| bombesin receptor subtyp...e-3 [Mus musculus] dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like recep...tor 3 [Mus musculus] gb|AAI06962.1| Bombesin-like receptor 3 [Mus musculus] emb|CAM25500.1| bombes...in-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 1e-172 78% ...

  14. NCBI nr-aa BLAST: CBRC-BTAU-01-1571 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-BTAU-01-1571 ref|NP_033896.2| bombesin-like receptor 3 [Mus musculus] sp|O54798|BRS3_MOUSE Bombes...in receptor subtype-3 (BRS-3) dbj|BAA24404.1| bombesin receptor subtype-3 [Mus musculus] ...dbj|BAC30064.1| unnamed protein product [Mus musculus] gb|AAI06963.1| Bombesin-like receptor 3 [Mus musculus] gb|AAI06962.1| Bombes...in-like receptor 3 [Mus musculus] emb|CAM25500.1| bombesin...-like receptor 3 [Mus musculus] gb|EDL42160.1| bombesin-like receptor 3 [Mus musculus] NP_033896.2 0.0 84% ...

  15. InterProScan Result: NM_001134239 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134239 NM_001134239_3_ORF2 9C6209F61E5A8E68 PRINTS PR00358 BOMBESINR 4.4e-05 T IPR001556 Bombes...in receptor Molecular Function: bombesin receptor activity (GO:0004946)|Biological Process

  16. InterProScan Result: NM_001134240 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134240 NM_001134240_1_ORF2 8F7EFB5ECDE1E93B PRINTS PR00358 BOMBESINR 1.2e-06 T IPR001556 Bombes...in receptor Molecular Function: bombesin receptor activity (GO:0004946)|Biological Process

  17. Gastrin releasing peptide receptor expression is decreased in patients with Crohn’s disease but not in ulcerative colitis

    OpenAIRE

    ter Beek, W P; Muller, E S M; van Hogezand, R A; Biemond, I; Lamers, C B H W

    2004-01-01

    Background: Gastrin releasing peptide (GRP) and neuromedin B are bombesin (BN)-like peptides involved in regulating motility and inflammation in the gastrointestinal tract, which may be useful in treating inflammatory bowel disease (IBD). Three bombesin-like peptide receptors have been reported, but no studies have investigated their localisation in normal and inflamed human intestine.

  18. InterProScan Result: NM_001134240 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134240 NM_001134240_1_ORF2 8F7EFB5ECDE1E93B PRINTS PR00358 BOMBESINR 1.2e-06 T IPR001556 Bombe...sin receptor Molecular Function: bombesin receptor activity (GO:0004946)|Biological Process

  19. InterProScan Result: NM_001134239 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001134239 NM_001134239_3_ORF2 9C6209F61E5A8E68 PRINTS PR00358 BOMBESINR 4.4e-05 T IPR001556 Bombe...sin receptor Molecular Function: bombesin receptor activity (GO:0004946)|Biological Process

  20. Physiological Function of Gastrin-Releasing Peptide and Neuromedin B Receptors in Regulating Itch Scratching Behavior in the Spinal Cord of Mice

    OpenAIRE

    Sukhtankar, Devki D.; Mei-Chuan Ko

    2013-01-01

    Pruritus (itch) is a severe side effect associated with the use of drugs as well as hepatic and hematological disorders. Previous studies in rodents suggest that bombesin receptor subtypes i.e. receptors for gastrin-releasing peptide (GRPr) and neuromedin B (NMBr) differentially regulate itch scratching. However, to what degree spinal GRPr and NMBr regulate scratching evoked by intrathecally administered bombesin-related peptides is not known. The first aim of this study was to pharmacologica...

  1. The Role of Central Gastrin-Releasing Peptide and Neuromedin B Receptors in the Modulation of Scratching Behavior in Rats

    OpenAIRE

    Su, Pin-Yen; Ko, Mei-Chuan

    2011-01-01

    Bombesin is a pruritogenic agent that causes intense itch-scratching activity in rodents. Bombesin has high affinity for the gastrin-releasing peptide (GRP) receptor (GRPr) and the neuromedin B (NMB) receptor (NMBr). The aim of this study was to investigate pharmacologically the ability of GRPr and NMBr to elicit scratching behavior in rats. The intracerebroventricular route was selected for drug delivery because the study focused on supraspinal sites of action. The magnitude and duration of ...

  2. Interrelationship between growth factor-induced pH changes and intracellular Ca/sup 2 +/

    Energy Technology Data Exchange (ETDEWEB)

    Ives, H.E.; Daniel, T.O.

    1987-04-01

    Many mitogens cause rapid changes in intracellular pH and Ca/sup 2 +/. The authors studied the patterns of pH and Ca/sup 2 +/ changes after exposure of murine fibroblasts to platelet-derived growth factor (PDGF), bombesin, phorbol 12-myristate 13-acetate (PMA), and the vasoactive peptide bradykinin. Intracellular pH and Ca/sup 2 +/ were measured by using the fluorescent dyes 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein and fura-2. Three distinct patterns of intracellular pH change were observed. (i) PDGF and bombesin caused a rapid cytoplasmic acidification of 0.03 pH unit followed by a slower alkalinization of approx. = 0.11 pH unit above the resting pH of 6.88. (ii) PMA caused alkalinization without causing the early acidification. (iii) Bradykinin caused rapid acidification without the slower net alkalinization. All acidification responses were amiloride resistant. Patterns of intracellular Ca/sup 2 +/ response were also determined for each agent. In Ca/sup 2 +/-buffered cells, PDGF, bombesin, bradykinin, and ionomycin failed to induce cellular acidification, but alkalinization responses to PDGF, bombesin, and PMA persisted. They propose that the transient acidification seen with PDGF, bombesin, and other agents is the result of increased intracellular Ca/sup 2 +/. However, growth factor-induced alkalinization via the Na/sup +//H/sup +/ exchanger is independent of changes in Ca/sup 2 +/.

  3. Comparison of two peptide radiotracers for prostate carcinoma targeting

    Directory of Open Access Journals (Sweden)

    Bluma Linkowski Faintuch

    2012-01-01

    Full Text Available OBJECTIVES: Scintigraphy is generally not the first choice treatment for prostate cancer, although successful studies using bombesin analog radiopeptides have been performed. Recently, a novel peptide obtained using a phage display library demonstrated an affinity for prostate tumor cells. The aim of this study was to compare the use of a bombesin analog to that of a phage display library peptide (DUP-1 radiolabeled with technetium-99m for the treatment of prostate carcinoma. The peptides were first conjugated to S-acetyl-MAG3 with a 6-carbon spacer, namely aminohexanoic acid. METHODS: The technetium-99m labeling required a sodium tartrate buffer. Radiochemical evaluation was performed using ITLC and was confirmed by high-performance liquid chromatography. The coefficient partition was determined, and in vitro studies were performed using human prostate tumor cells. Biodistribution was evaluated in healthy animals at various time points and also in mice bearing tumors. RESULTS: The radiochemical purity of both radiotracers was greater than 95%. The DUP-1 tracer was more hydrophilic (log P = -2.41 than the bombesin tracer (log P = -0.39. The biodistribution evaluation confirmed this hydrophilicity by revealing the greater kidney uptake of DUP-1. The bombesin concentration in the pancreas was greater than that of DUP-1 due to specific gastrin-releasing peptide receptors. Bombesin internalization occurred for 78.32% of the total binding in tumor cells. The DUP-1 tracer showed very low binding to tumor cells during the in vitro evaluation, although tumor uptake for both tracers was similar. The tumors were primarily blocked by DUP1 and the bombesin radiotracer primarily targeted the pancreas. CONCLUSION: Further studies with the radiolabeled DUP-1 peptide are recommended. With further structural changes, this molecule could become an efficient alternative tracer for prostate tumor diagnosis.

  4. Coexistence of neuropeptides in hydra

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J

    1983-01-01

    Using a technique for simultaneous visualisation of two antigens in one section, oxytocin-like immunoreactivity has been found to coexist with bombesin-like immunoreactivity in neurons of the basal disk, gastric region and tentacles of hydra. Neurons with oxytocin-like immunoreactivity in peduncl......, as well as non-coexistence, of neuropeptides is a phylogenetically old principle....

  5. Physiological function of gastrin-releasing peptide and neuromedin B receptors in regulating itch scratching behavior in the spinal cord of mice.

    Directory of Open Access Journals (Sweden)

    Devki D Sukhtankar

    Full Text Available Pruritus (itch is a severe side effect associated with the use of drugs as well as hepatic and hematological disorders. Previous studies in rodents suggest that bombesin receptor subtypes i.e. receptors for gastrin-releasing peptide (GRPr and neuromedin B (NMBr differentially regulate itch scratching. However, to what degree spinal GRPr and NMBr regulate scratching evoked by intrathecally administered bombesin-related peptides is not known. The first aim of this study was to pharmacologically compare the dose-response curves for scratching induced by intrathecally administered bombesin-related peptides versus morphine, which is known to elicit itch in humans. The second aim was to determine if spinal GRPr and NMBr selectively or generally mediate scratching behavior. Mice received intrathecal injection of bombesin (0.01-0.3 nmol, GRP (0.01-0.3 nmol, NMB (0.1-1 nmol or morphine (0.3-3 nmol and were observed for one hour for scratching activity. Bombesin elicited most profound scratching over one hour followed by GRP and NMB, whereas morphine failed to evoke scratching response indicating the insensitivity of mouse models to intrathecal opioid-induced itch. Intrathecal pretreatment with GRPr antagonist RC-3095 (0.03-0.1 nmol produced a parallel rightward shift in the dose response curve of GRP-induced scratching but not NMB-induced scratching. Similarly, PD168368 (1-3 nmol only attenuated NMB but not GRP-induced scratching. Individual or co-administration of RC-3095 and PD168368 failed to alter bombesin-evoked scratching. A higher dose of RC-3095 (0.3 nmol generally suppressed scratching induced by all three peptides but also compromised motor function in the rotarod test. Together, these data indicate that spinal GRPr and NMBr independently drive itch neurotransmission in mice and may not mediate bombesin-induced scratching. GRPr antagonists at functionally receptor-selective doses only block spinal GRP-elicited scratching but the suppression of

  6. Physiological function of gastrin-releasing peptide and neuromedin B receptors in regulating itch scratching behavior in the spinal cord of mice.

    Science.gov (United States)

    Sukhtankar, Devki D; Ko, Mei-Chuan

    2013-01-01

    Pruritus (itch) is a severe side effect associated with the use of drugs as well as hepatic and hematological disorders. Previous studies in rodents suggest that bombesin receptor subtypes i.e. receptors for gastrin-releasing peptide (GRPr) and neuromedin B (NMBr) differentially regulate itch scratching. However, to what degree spinal GRPr and NMBr regulate scratching evoked by intrathecally administered bombesin-related peptides is not known. The first aim of this study was to pharmacologically compare the dose-response curves for scratching induced by intrathecally administered bombesin-related peptides versus morphine, which is known to elicit itch in humans. The second aim was to determine if spinal GRPr and NMBr selectively or generally mediate scratching behavior. Mice received intrathecal injection of bombesin (0.01-0.3 nmol), GRP (0.01-0.3 nmol), NMB (0.1-1 nmol) or morphine (0.3-3 nmol) and were observed for one hour for scratching activity. Bombesin elicited most profound scratching over one hour followed by GRP and NMB, whereas morphine failed to evoke scratching response indicating the insensitivity of mouse models to intrathecal opioid-induced itch. Intrathecal pretreatment with GRPr antagonist RC-3095 (0.03-0.1 nmol) produced a parallel rightward shift in the dose response curve of GRP-induced scratching but not NMB-induced scratching. Similarly, PD168368 (1-3 nmol) only attenuated NMB but not GRP-induced scratching. Individual or co-administration of RC-3095 and PD168368 failed to alter bombesin-evoked scratching. A higher dose of RC-3095 (0.3 nmol) generally suppressed scratching induced by all three peptides but also compromised motor function in the rotarod test. Together, these data indicate that spinal GRPr and NMBr independently drive itch neurotransmission in mice and may not mediate bombesin-induced scratching. GRPr antagonists at functionally receptor-selective doses only block spinal GRP-elicited scratching but the suppression of scratching

  7. NCBI nr-aa BLAST: CBRC-MDOM-02-0380 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MDOM-02-0380 ref|NP_002502.2| neuromedin B receptor [Homo sapiens] sp|P28336|N...eceptor emb|CAH70473.1| neuromedin B receptor [Homo sapiens] gb|EAW47886.1| neuromedin B receptor [Homo sapiens] NP_002502.2 0.0 85% ... ...MBR_HUMAN RecName: Full=Neuromedin-B receptor; Short=NMB-R; AltName: Full=Neuromedin-B-preferring bombesin r

  8. NCBI nr-aa BLAST: CBRC-PVAM-01-1297 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PVAM-01-1297 ref|NP_002502.2| neuromedin B receptor [Homo sapiens] sp|P28336|N...eceptor emb|CAH70473.1| neuromedin B receptor [Homo sapiens] gb|EAW47886.1| neuromedin B receptor [Homo sapiens] NP_002502.2 2e-67 89% ... ...MBR_HUMAN RecName: Full=Neuromedin-B receptor; Short=NMB-R; AltName: Full=Neuromedin-B-preferring bombesin r

  9. NCBI nr-aa BLAST: CBRC-GGOR-01-0405 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GGOR-01-0405 ref|NP_002502.2| neuromedin B receptor [Homo sapiens] sp|P28336|N...eceptor emb|CAH70473.1| neuromedin B receptor [Homo sapiens] gb|EAW47886.1| neuromedin B receptor [Homo sapiens] NP_002502.2 4e-60 98% ... ...MBR_HUMAN RecName: Full=Neuromedin-B receptor; Short=NMB-R; AltName: Full=Neuromedin-B-preferring bombesin r

  10. NCBI nr-aa BLAST: CBRC-MLUC-01-0869 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0869 ref|NP_002502.2| neuromedin B receptor [Homo sapiens] sp|P28336|N...eceptor emb|CAH70473.1| neuromedin B receptor [Homo sapiens] gb|EAW47886.1| neuromedin B receptor [Homo sapiens] NP_002502.2 1e-159 78% ... ...MBR_HUMAN RecName: Full=Neuromedin-B receptor; Short=NMB-R; AltName: Full=Neuromedin-B-preferring bombesin r

  11. NCBI nr-aa BLAST: CBRC-OPRI-01-0886 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-0886 ref|NP_002502.2| neuromedin B receptor [Homo sapiens] sp|P28336|N...eceptor emb|CAH70473.1| neuromedin B receptor [Homo sapiens] gb|EAW47886.1| neuromedin B receptor [Homo sapiens] NP_002502.2 1e-59 85% ... ...MBR_HUMAN RecName: Full=Neuromedin-B receptor; Short=NMB-R; AltName: Full=Neuromedin-B-preferring bombesin r

  12. Organelle selection determines agonist-specific Ca2+ signals in pancreatic acinar and beta cells

    OpenAIRE

    Yamasaki, M.; Masgrau, R.; Morgan, A. J.; Churchill, G. C.; Patel, S.; Ashcroft, S. J. H.; Galione, A

    2004-01-01

    How different extracellular stimuli can evoke different spatiotemporal Ca2+ signals is uncertain. We have elucidated a novel paradigm whereby different agonists use different Ca2+-storing organelles ("organelle seleetion") to evoke unique responses. Some agonists select the endoplasmic reticulum (ER), and others select lysosome-related (acidic) organelles, evoking spatial Ca2+ responses that mirror the organellar distribution. In pancreatic acinar cells, acetylcholine and bombesin exclusively...

  13. The interaction of bioactive peptides with an immobilized phosphatidylcholine monolayer.

    OpenAIRE

    Mozsolits, H; Lee, T. H.; Wirth, H J; Perlmutter, P; Aguilar, M I

    1999-01-01

    The interaction of three bioactive peptides, bombesin, beta-endorphin, and glucagon with a phosphatidylcholine monolayer that was immobilized to porous silica particles and packed into a stainless steel column cartridge, has been studied using dynamic elution techniques. This immobilized lipid monolayer provides a biophysical model system with which to study the binding of peptides to a lipid membrane. In particular, the influence of temperature and methanol concentration on the affinity of e...

  14. Isolation and sequence of a cDNA encoding the precursor of a bombesinlike peptide from brain and early embryos of Xenopus laevis.

    OpenAIRE

    Wechselberger, C; Kreil, G; Richter, K.

    1992-01-01

    A cDNA encoding the precursor of a bombesinlike peptide was isolated from brain of Xenopus laevis. The predicted end product resembles neuromedin B, which was originally isolated from mammalian spinal cord. The mRNA for this precursor was also present in gastrointestinal tract and in ovaries. Moreover, it could be detected in early embryos (stage 2 and stage 10) of X. laevis. These findings suggest novel roles for peptides of the bombesin family in oocyte maturation and early amphibian develo...

  15. Conformational ensembles of neuromedin C reveal a progressive coil-helix transition within a binding-induced folding mechanism

    OpenAIRE

    Roca Adrover, Miquel; Sanchis, Pilar; Vilanova, Bartolome; Pauwels, Kris; Martorell, Gabriel; Pérez González, Juan Jesús

    2015-01-01

    Neuromedin C (NMC) is a peptide that regulates various processes in the central nervous system and gastrointestinal tract through its interaction with the bombesin receptor subtype-2 (BB2R). Hence, BB2R antagonists hold the potential to treat disorders that occur as a result of NMC dysfunction or misregulation. However, their efficient design requires a detailed understanding of the structural features of NMC, which hitherto are unknown. Herein, we describe the conformational ensembles of NMC...

  16. Neuromedin B and Its Receptor: Gene Cloning, Tissue Distribution and Expression Levels of the Reproductive Axis in Pigs

    OpenAIRE

    Zhiyu Ma; Juan Su; Tingting Guo; Mengmeng Jin; Xiang Li; Zhihai Lei; Yuanlong Hou; Xiaoliang Li; Cuicui Jia; Zheng Zhang; Ejlal Ahmed

    2016-01-01

    Neuromedin B is one member of a family of bombesin-like peptides, which performs a variety of physiological functions via their receptor (NMBR) in most mammals. However, the genes encoding NMB and NMBR and their functions especially reproduction of the pigs are currently not fully understood. To research the physiological functions of NMB, we cloned and analyzed the NMB and NMBR genes, and systematically investigated the expression levels of NMB and NMBR mRNA using relative real-time PCR and ...

  17. Novel dimeric DOTA-coupled peptidic Y1-receptor antagonists for targeting of neuropeptide Y receptor-expressing cancers

    OpenAIRE

    Chatenet, David; Cescato, Renzo; Waser, Beatrice; Erchegyi, Judit; Jean E Rivier; Reubi, Jean Claude

    2011-01-01

    Background Several peptide hormone receptors were identified that are specifically over-expressed on the cell surface of certain human tumors. For example, high incidence and density of the Y1 subtype of neuropeptide Y (NPY) receptors are found in breast tumors. Recently, we demonstrated that the use of potent radiolabeled somatostatin or bombesin receptor antagonists considerably improved the sensitivity of in vivo imaging when compared to agonists. We report here on the first DOTA-coupled p...

  18. NCBI nr-aa BLAST: CBRC-FRUB-02-0194 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FRUB-02-0194 ref|NP_005305.1| gastrin-releasing peptide receptor [Homo sapiens...] sp|P30550|GRPR_HUMAN Gastrin-releasing peptide receptor (GRP-R) (GRP-preferring bombesin receptor) gb|AAA88050.1| gastrin releasing... peptide receptor gb|AAB27329.1| gastrin-releasing peptide receptor, GRP receptor=b...ng peptide receptor [Homo sapiens] gb|AAH74733.1| Gastrin-releasing peptide recepto...r [Homo sapiens] gb|EAW98909.1| gastrin-releasing peptide receptor [Homo sapiens] NP_005305.1 1e-128 66% ...

  19. NCBI nr-aa BLAST: CBRC-RMAC-21-0006 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RMAC-21-0006 ref|NP_005305.1| gastrin-releasing peptide receptor [Homo sapiens...] sp|P30550|GRPR_HUMAN Gastrin-releasing peptide receptor (GRP-R) (GRP-preferring bombesin receptor) gb|AAA88050.1| gastrin releasing... peptide receptor gb|AAB27329.1| gastrin-releasing peptide receptor, GRP receptor=b...ng peptide receptor [Homo sapiens] gb|AAH74733.1| Gastrin-releasing peptide recepto...r [Homo sapiens] gb|EAW98909.1| gastrin-releasing peptide receptor [Homo sapiens] NP_005305.1 0.0 98% ...

  20. Role of neuromedin B in the control of the release of thyrotropin in the rat.

    OpenAIRE

    Rettori, V; Milenkovic, L; Fahim, A M; J. Polak; Bloom, S R; McCann, S M

    1989-01-01

    Neuromedin B (NB), a bombesin-like peptide, was first isolated from porcine spinal cord and subsequently found in the central nervous systems of rat, cat, and human. Immunocytochemical studies have shown that NB is present in hypothalamus and various other regions of the brain and in thyrotrophs of the anterior pituitary of the rat. The possible physiological role of NB in the hypothalamic-pituitary axis is not known. Therefore, we studied the in vivo effect of this peptide on the plasma leve...

  1. Neuromedin B receptors regulate EGF receptor tyrosine phosphorylation in lung cancer cells

    OpenAIRE

    Moody, Terry W.; Berna, Marc J.; Mantey, Samuel; Sancho, Veronica; Ridnour, Lisa; Wink, David A.; Chan, Daniel; Giaccone, Giuseppe; Jensen, Robert T.

    2010-01-01

    Neuromedin B (NMB), a member of the bombesin family of peptides, is an autocrine growth factor for many lung cancer cells. The present study investigated the ability of NMB to cause transactivation of the epidermal growth factor (EGF) receptor in lung cancer cells. By Western blot, addition of NMB or related peptides to NCI-H1299 human non-small cell lung cancer (NSCLC) cells, caused phosphorylation of Tyr1068 of the EGF receptor. The signal was amplified using NCI-H1299 cells stably transect...

  2. Synthesis, stabilization and formulation of [177Lu]Lu-AMBA, a systemic radiotherapeutic agent for Gastrin Releasing Peptide receptor positive tumors

    International Nuclear Information System (INIS)

    A robust formulation was developed for [177Lu]Lu-AMBA (177Lu-DO3A-CH2CO-G-[4-aminobenzoyl]-QWAVGHLM-NH2), a Bombesin-like agonist with high affinity for Gastrin Releasing Peptide (GRP) receptors. During optimization of labeling, the effect of several radiostabilizers was evaluated; a combination of selenomethionine and ascorbic acid showed superiority over other tested radiostabilizers. The resulting two-vial formulation maintains a radiochemical purity (RCP) of >90% for at least 2 days at room temperature. The method of stabilization should be useful for other methionine-containing peptide radiopharmaceuticals in diagnostic and therapeutic applications

  3. FMRFamide immunoreactivity in the nervous system of the medusa Polyorchis penicillatus

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J; Spencer, A N

    1984-01-01

    Three different antisera to the molluscan neuropeptide Phe-Met-Arg-Phe-amide (FMRFamide) and two different antisera to the fragment RFamide were used to stain sections or whole mounts of the hydrozoan medusa Polyorchis penicillatus. All antisera stained the same neuronal structures. Strong immuno...... with several antisera to oxytocin/vasopressin and bombesin/gastrin-releasing peptide. The morphology and location of most FMRFamide-immunoreactive neurons in Polyorchis coincides with two identified neuronal systems, which have been recently discovered from neurophysiological studies....

  4. Development of PET molecular targeting agents with gallium-68

    International Nuclear Information System (INIS)

    The utilization of positron emission tomography (PET) is increasing due to its superior imaging quality and its ability to be used for in vivo quantification. Radionuclides that decay by positron emission can be attached to the same chelators used for radiotherapy applications in diagnosis and staging. One such isotope is 68Ga (T1/2 = 68 min), which can be obtained from a long-lived generator by decay of the parent 68Ge (T1/2 = 270.8 d). The availability of 68Ga from a generator plus its ability to be stably incorporated with a variety of chelates hold promise for expanding PET utilization to facilities unable to afford their own cyclotron. In collaboration with researchers at the University of Missouri, we have developed and evaluated peptides that target the melanocortin-1 receptor and the gastrin-releasing peptide (GRP) receptor for peptide guided imaging and therapy. The melanocortin-1 receptor is an attractive target for peptide guided melanoma imaging and therapy. The limited number of receptors per cell, approximately 900-5000, requires high specific activity radiolabeled peptide ligands to prevent target saturation and ensure optimal cellular uptake. GRP receptors are over-expressed by a variety of human cancers such as breast, lung, pancreatic and prostate tumors, and due to bombesin's toxicity, it is necessary to label it in high specific activity. Results are presented on NOTA and DOTA bifunctionalized α-MSH and bombesin peptides, highlighting the differences in specific activity, preparation time and in vivo characteristics.

  5. Biokinetics and dosimetry of several radiolabelled peptides in cancer cells

    Science.gov (United States)

    Rodríguez-Cortés, J.; Ferro-Flores, G.; de Murphy, C. Arteaga; Pedraza-López, M.; Ramírez-Iglesias, M. A. T.

    Radiolabelled peptides have been used as target-specific radiopharmaceuticals. The goal of this research was the in vitro assessment of the uptake, internalization, externalization, and efflux of five radiolabelled peptides in cancer cells to estimate radiation-absorbed doses from experimental biokinetic data. 177Lu-DOTA-octreotate, 188Re-lanreotide, and 99mTc-HYNIC-octreotide were studied in the AR42J cell line. The PC3 and NCIH69 cells were used for 99mTc-HYNIC-bombesin and 177Lu-DOTA-minigastrin, respectively. The cumulated activities in the membrane and cytoplasm were calculated by integration of the experimental time-activity curves and used for dosimetry calculations according to the Medical Internal Radiation Dose (MIRD) cellular methodology. The mean absorbed dose to the cell nucleus were 0.69±0.09, 0.11±0.08, 0.55±0.09, 3.45±0.48, and 3.30±0.65 Gy/Bq for 99mTc-HYNIC-bombesin, 99mTc-HYNIC-octreotide, 177Lu-DOTA-minigastrin, 177Lu-DOTA-octreotate, and 188Re-lanreotide, respectively. If radiopharmaceutical cell kinetics were not used and only uptake data were considered, the calculated doses would be overestimated up to 25 times.

  6. Influence of breast feeding on blood level of gastrointestinal hormone in preterm infants%母乳喂养对早产新生儿血胃肠激素水平的影响

    Institute of Scientific and Technical Information of China (English)

    刘晓莹; 孙建华; 李菁; 步军; 谢恩萍

    2013-01-01

    Objective To understand the influence of breast feeding on the blood level of gastrointestinal hormone in preterm infants. Methods Radio-immunoassay was used to detect the blood levels of gastrin and bombesin of 27 cases ( experimental group ) with breast feeding at 3rd, 7th and 14th day of enteral feeding. Another 33 preterm infants fed with formula milk were taken as control group. Meanwhile the blood levels of gastrin and bombesin at 3rd and 7th day after delivery were detected. Results The levels of gastrin and bombesin of infants with breast feeding were higher on the 3rd day than those on the 7th day after delivery ( t = 6. 526, P = 0. 000; t = 2. 222,P =0. 042 ). Within 2 weeks of enteral feeding, the blood level of gastrin in experimental group had no significant change( F =0. 335,P =0. 722 ), but that of bombesin was descending( F = 5.060,P =0. 021 )and it descended significantly on the 14th day ( F =7. 932,P =0. 009 ). However, in the control group the blood level of gastrin was increasing( F = 5. 147,P =0. 015 ), and that on the 7th day was obviously higher than that on the 3rd day ( F = 5. 126, P < 0. 05 ). The blood level of bombesin had no significant change( F = 1. 147,P =0. 334 ). Conclusion The blood levels of gastrin and bombesin in preterm infants with breast feeding are relatively high, and they are descending within 1 week after delivery. The change tendency of the blood levels of gastrin and bombesin is different between the experimental group and the control group, and it needs further study.%目的 探讨母乳喂养对早产新生儿血胃肠激素水平的影响.方法 采用放射免疫法测定27例母乳喂养早产儿(实验组)肠内喂养第3天、7天及14天时餐前血清胃泌素、血浆蛙皮素浓度,并以33例早产配方奶粉喂养早产儿作为对照组;同时测定分娩后第3天、7天早产母乳胃泌素、蛙皮素浓度.结果 分娩后第3天早产母乳胃泌素、蛙皮素浓度均高于分娩后第7天(t=6

  7. Receptors for sensory neuropeptides in human inflammatory diseases: Implications for the effector role of sensory neurons

    International Nuclear Information System (INIS)

    Glutamate and several neuropeptides are synthesized and released by subpopulations of primary afferent neurons. These sensory neurons play a role in regulating the inflammatory and immune responses in peripheral tissues. Using quantitative receptor autoradiography we have explored what changes occur in the location and concentration of receptor binding sites for sensory neurotransmitters in the colon in two human inflammatory diseases, ulcerative colitis and Crohn's disease. The sensory neurotransmitter receptors examined included bombesin, calcitonin gene related peptide-alpha, cholecystokinin, galanin, glutamate, somatostatin, neurokinin A (substance K), substance P, and vasoactive intestinal polypeptide. Of the nine receptor binding sites examined only substance P binding sites associated with arterioles, venules and lymph nodules were dramatically up-regulated in the inflamed tissue. These data suggest that substance P is involved in regulating the inflammatory and immune responses in human inflammatory diseases and indicate a specificity of efferent action for each sensory neurotransmitter in peripheral tissues

  8. Involvement of the mitogen-activated protein (MAP kinase signalling pathway in host cell invasion by Toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Robert-Gangneux F.

    2000-06-01

    Full Text Available Little is known about signalling in Toxoplasma gondii, but it is likely that protein kinases might play a key role in the parasite proliferation, differentiation and probably invasion. We previously characterized Mitogen-Activated Protein (MAP kinases in T. gondii lysates. In this study, cultured cells were tested for their susceptibility to Toxoplasma gondii infection after tachyzoite pretreatment with drugs interfering with AMP kinase activation pathways. Protein kinases inhibitors, i.e. genistein, R031-8220 and PD098059, reduced tachyzoite infectivity by 38 ± 4.5 %, 85.5 ± 9 % and 56 ± 10 %, respectively. Conversely, protein kinases activators, i.e. bombesin and PMA, markedly increased infectivity (by 202 ± 37 % and 258 ± 14 %, respectively. These results suggest that signalling pathways involving PKC and AAAP kinases play a role in host cell invasion by Toxoplasma.

  9. Radiolabelled peptides for oncological diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Laverman, Peter; Boerman, Otto C.; Oyen, Wim J.G. [Radboud University Nijmegen Medical Centre, Department of Nuclear Medicine, Nijmegen (Netherlands); Sosabowski, Jane K. [Queen Mary University of London, Centre for Molecular Oncology, Barts Cancer Institute, London (United Kingdom)

    2012-02-15

    Radiolabelled receptor-binding peptides targeting receptors (over)expressed on tumour cells are widely under investigation for tumour diagnosis and therapy. The concept of using radiolabelled receptor-binding peptides to target receptor-expressing tissues in vivo has stimulated a large body of research in nuclear medicine. The {sup 111}In-labelled somatostatin analogue octreotide (OctreoScan trademark) is the most successful radiopeptide for tumour imaging, and was the first to be approved for diagnostic use. Based on the success of these studies, other receptor-targeting peptides such as cholecystokinin/gastrin analogues, glucagon-like peptide-1, bombesin (BN), chemokine receptor CXCR4 targeting peptides, and RGD peptides are currently under development or undergoing clinical trials. In this review, we discuss some of these peptides and their analogues, with regard to their potential for radionuclide imaging of tumours. (orig.)

  10. Radiolabeled Peptides: Valuable Tools for the Detection and Treatment of Cancer

    Directory of Open Access Journals (Sweden)

    M. Fani, H. R. Maecke, S. M. Okarvi

    2012-01-01

    Full Text Available Human cancer cells overexpress many peptide receptors as molecular targets. Radiolabeled peptides that bind with high affinity and specificity to the receptors on tumor cells hold great potential for both diagnostic imaging and targeted radionuclide therapy. The advantage of solid-phase peptide synthesis, the availability of different chelating agents and prosthetic groups and bioconjugation techniques permit the facile preparation of a wide variety of peptide-based targeting molecules with diverse biological and tumor targeting properties. Some of these peptides, including somatostatin, bombesin, vasoactive intestinal peptide, gastrin, neurotensin, exendin and RGD are currently under investigation. It is anticipated that in the near future many of these peptides may find applications in nuclear oncology. This article presents recent developments in the field of small peptides, and their applications in the diagnosis and treatment of cancer.

  11. Interactions of Gastrointestinal Peptides: Ghrelin and Its Anorexigenic Antagonists

    Directory of Open Access Journals (Sweden)

    Anna-Sophia Wisser

    2010-01-01

    Full Text Available Food intake behaviour and energy homeostasis are strongly regulated by a complex system of humoral factors and nerval structures constituting the brain-gut-axis. To date the only known peripherally produced and centrally acting peptide that stimulates food intake is ghrelin, which is mainly synthesized in the stomach. Recent data indicate that the orexigenic effect of ghrelin might be influenced by other gastrointestinal peptides such as cholecystokinin (CCK, bombesin, desacyl ghrelin, peptide YY (PYY, as well as glucagon-like peptide (GLP. Therefore, we will review on the interactions of ghrelin with several gastrointestinal factors known to be involved in appetite regulation in order to elucidate the interdependency of peripheral orexigenic and anorexigenic peptides in the control of appetite.

  12. Immunohistochemical study on distribution of endocrine cells in gastrointestinal tract of flower fish (Pseudophoxinus antalyae)

    Institute of Scientific and Technical Information of China (English)

    Kenan (C)inar; Nurgül (S)enol; M Rü(s)tü (O)zen

    2006-01-01

    AIM:To detect distribution and relative frequency of endocrine cells in gastrointestinal tract of flower fish (Pseudophoxinus antalyae ).METHOIS:The intestinal tract of flower fish was divided into four portions from proximal to distal;the enlarged area after oesophagus and anterior, middle and posterior intestine. Immunohistochemical method using the peroxidase anti-peroxidase complex was employed.All antisera between four portions of flower fish were compared using ANOVA.RESULTS:Eleven types of gut endocrine cells were determined; they were immunoreactive for calcitonin gene related peptide, substance P, vasoactive intestinal peptide, bombesin, somatostatin-14, secretin, TrkA, TrkB,TrkC, neurotensin, neuropeptide Y, which were found in almost all portions of the gastrointestinal tract.CONCLUSION:The regional distribution and relative frequency of immunoreactive cells in the flower fish,Pseudophoxinus antalyae, are essentially similar to those of other fish.

  13. Development of PET molecular targeting agents with gallium-68

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, C.S.; Cantorias, M. [Univ. of Missouri Research Reactor Center (MURR), Columbia, MO (United States). Radiopharmaceutical Sciences Inst.; Sisay, N. [Univ. of Missouri, Columbia, MO (United States). Dept. of Chemistry; Galazzi, F.; Quinn, T.P. [Univ. of Missouri, Columbia, MO (United States). Dept. of Biochemistry; Smith, C.J. [Univ. of Missouri School of Medicine and Harry S. Truman Memorial Veterans Hospital, Columbia, MO (United States). Dept. of Radiology and Research Reactor Center

    2011-07-01

    The utilization of positron emission tomography (PET) is increasing due to its superior imaging quality and its ability to be used for in vivo quantification. Radionuclides that decay by positron emission can be attached to the same chelators used for radiotherapy applications in diagnosis and staging. One such isotope is {sup 68}Ga (T{sub 1/2} = 68 min), which can be obtained from a long-lived generator by decay of the parent {sup 68}Ge (T{sub 1/2} = 270.8 d). The availability of {sup 68}Ga from a generator plus its ability to be stably incorporated with a variety of chelates hold promise for expanding PET utilization to facilities unable to afford their own cyclotron. In collaboration with researchers at the University of Missouri, we have developed and evaluated peptides that target the melanocortin-1 receptor and the gastrin-releasing peptide (GRP) receptor for peptide guided imaging and therapy. The melanocortin-1 receptor is an attractive target for peptide guided melanoma imaging and therapy. The limited number of receptors per cell, approximately 900-5000, requires high specific activity radiolabeled peptide ligands to prevent target saturation and ensure optimal cellular uptake. GRP receptors are over-expressed by a variety of human cancers such as breast, lung, pancreatic and prostate tumors, and due to bombesin's toxicity, it is necessary to label it in high specific activity. Results are presented on NOTA and DOTA bifunctionalized {alpha}-MSH and bombesin peptides, highlighting the differences in specific activity, preparation time and in vivo characteristics.

  14. Radiolabelled peptides for tumour therapy: current status and future directions. Plenary lecture at the EANM 2002

    International Nuclear Information System (INIS)

    On their plasma membranes, cells express receptor proteins with high affinity for regulatory peptides, such as somatostatin. Changes in the density of these receptors during disease, e.g. overexpression in many tumours, provide the basis for new imaging methods. The first peptide analogues successfully applied for visualisation of receptor-positive tumours were radiolabelled somatostatin analogues. The next step was to label these analogues with therapeutic radionuclides for peptide receptor radionuclide therapy (PRRT). Results from preclinical and clinical multicentre studies have already shown an effective therapeutic response when using radiolabelled somatostatin analogues to treat receptor-positive tumours. Infusion of positively charged amino acids reduces kidney uptake, enlarging the therapeutic window. For PRRT of CCK-B receptor-positive tumours, such as medullary thyroid carcinoma, radiolabelled minigastrin analogues are currently being successfully applied. The combination of different therapy modalities holds interest as a means of improving the clinical therapeutic effects of radiolabelled peptides. The combination of different radionuclides, such as 177Lu- and 90Y-labelled somatostatin analogues, to reach a wider tumour region of high curability, has been described. A variety of other peptide-based radioligands, such as bombesin and NPY(Y1) analogues, receptors for which are expressed on common cancers such as prostate and breast cancer, are currently under development and in different phases of (pre)clinical investigation. Multi-receptor tumour targeting using the combination of bombesin and NPY(Y1) analogues is promising for scintigraphy and PRRT of breast carcinomas and their lymph node metastases. (orig.)

  15. An analysis of cosecretion and coexpression of gut hormones from male rat proximal and distal small intestine.

    Science.gov (United States)

    Svendsen, Berit; Pedersen, Jens; Albrechtsen, Nicolai Jacob Wewer; Hartmann, Bolette; Toräng, Signe; Rehfeld, Jens F; Poulsen, Steen Seier; Holst, Jens Juul

    2015-03-01

    Gut endocrine cells are generally thought to have distinct localization and secretory products. Recent studies suggested that the cells are highly related and have potential to express more than one hormone. We studied the coexpression and cosecretion of gut hormones in separate segments of rat small intestine. We measured secretion of glucagon-like peptide-1 (GLP-1), peptide YY (PYY), neurotensin, glucose-dependent insulinotropic polypeptide (GIP), and cholecystokinin (CCK) from proximal and distal half of the small intestine, isolated from male rats and perfused ex vivo. Hormone secretion was stimulated by bombesin, the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine, and peptones. Furthermore, tissue samples collected along the intestine were analyzed for expression, hormone content, and cell densities including colocalization. Most hormones responded to all three stimuli (but no GIP response to bombesin). GLP-1 secretion was similar from proximal and distal intestine, whereas PYY was secreted only from the distal half. CCK and GIP were mainly secreted proximally, whereas neurotensin was equally secreted from both parts. Cell densities, hormone concentrations, and expression patterns were generally parallel, with increasing values distally for GLP-1 and PYY, an exclusively proximal pattern for CCK, even distribution for neurotensin and GIP except for the most distal segments. PYY nearly always colocalized with GLP-1. Approximately 20% of GLP-1 cells colocalized with CCK and neurotensin, whereas GLP-1/GIP colocalization was rare. Our findings indicate that two L cell types exist, a proximal one secreting GLP-1 (and possibly CCK and neurotensin), and a distal one secreting GLP-1 and PYY. GIP seems to be secreted from cells that are not cosecreting other peptides.

  16. Neuromedin B stimulates the hypothalamic-pituitary-gonadal axis in male rats.

    Science.gov (United States)

    Boughton, C K; Patel, S A; Thompson, E L; Patterson, M; Curtis, A E; Amin, A; Chen, K; Ghatei, M A; Bloom, S R; Murphy, K G

    2013-11-10

    Neuromedin B (NMB) is a highly conserved bombesin-related peptide found in mammals. NMB mRNA is detected in the central nervous system (CNS) and is highly expressed in the rat hypothalamus, in particular the medial preoptic area and the arcuate nucleus. The mammalian bombesin family of receptors consists of three closely related G protein coupled receptors, BB1, BB2 and BB3. The BB1 receptor subtype has the highest affinity for NMB. NMB has well documented roles in the regulation of the thyroid axis and the stress axis in rats. However, there is little available data regarding the role of NMB in the regulation of the hypothalamic-pituitary-gonadal (HPG) axis. It is known that the NMB receptor is expressed in immortalised gonadotrophin releasing hormone (GnRH) releasing GT1-7 cells and murine forebrain GnRH neurons, and that anterior pituitary NMB-immunoreactivity is altered by changes in the sex steroid environment. The objective of these studies was thus to further investigate the effects of NMB on the HPG axis. Intracerebroventricular (ICV) administration of NMB (10 nmol) to adult male rats significantly increased plasma luteinising hormone (LH) levels 30 min after injection (plasma LH ng/ml; saline 0.69±0.07, 10 nmol NMB 1.33±0.17, P<0.01). In vitro, NMB stimulated GnRH release from hypothalamic explants from male rats and from hypothalamic GT1-7 cells. NMB had no significant effect on LH release from anterior pituitary explants from male rats, or from pituitary LβT2 cells in vitro. These results suggest a previously unreported role for NMB in the stimulation of the HPG axis via hypothalamic GnRH. Further work is now required to determine the receptor mediating the effects of NMB on the reproductive axis and the physiological role of NMB in reproduction. PMID:24120470

  17. Radiopharmaceutical development of radiolabelled peptides

    Energy Technology Data Exchange (ETDEWEB)

    Fani, Melpomeni; Maecke, Helmut R. [University Hospital Freiburg, Department of Nuclear Medicine, Freiburg (Germany)

    2012-02-15

    Receptor targeting with radiolabelled peptides has become very important in nuclear medicine and oncology in the past few years. The overexpression of many peptide receptors in numerous cancers, compared to their relatively low density in physiological organs, represents the molecular basis for in vivo imaging and targeted radionuclide therapy with radiolabelled peptide-based probes. The prototypes are analogs of somatostatin which are routinely used in the clinic. More recent developments include somatostatin analogs with a broader receptor subtype profile or with antagonistic properties. Many other peptide families such as bombesin, cholecystokinin/gastrin, glucagon-like peptide-1 (GLP-1)/exendin, arginine-glycine-aspartic acid (RGD) etc. have been explored during the last few years and quite a number of potential radiolabelled probes have been derived from them. On the other hand, a variety of strategies and optimized protocols for efficient labelling of peptides with clinically relevant radionuclides such as {sup 99m}Tc, M{sup 3+} radiometals ({sup 111}In, {sup 86/90}Y, {sup 177}Lu, {sup 67/68}Ga), {sup 64/67}Cu, {sup 18}F or radioisotopes of iodine have been developed. The labelling approaches include direct labelling, the use of bifunctional chelators or prosthetic groups. The choice of the labelling approach is driven by the nature and the chemical properties of the radionuclide. Additionally, chemical strategies, including modification of the amino acid sequence and introduction of linkers/spacers with different characteristics, have been explored for the improvement of the overall performance of the radiopeptides, e.g. metabolic stability and pharmacokinetics. Herein, we discuss the development of peptides as radiopharmaceuticals starting from the choice of the labelling method and the conditions to the design and optimization of the peptide probe, as well as some recent developments, focusing on a selected list of peptide families, including somatostatin

  18. The Nutrient-Responsive Hormone CCHamide-2 Controls Growth by Regulating Insulin-like Peptides in the Brain of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Hiroko Sano

    2015-05-01

    Full Text Available The coordination of growth with nutritional status is essential for proper development and physiology. Nutritional information is mostly perceived by peripheral organs before being relayed to the brain, which modulates physiological responses. Hormonal signaling ensures this organ-to-organ communication, and the failure of endocrine regulation in humans can cause diseases including obesity and diabetes. In Drosophila melanogaster, the fat body (adipose tissue has been suggested to play an important role in coupling growth with nutritional status. Here, we show that the peripheral tissue-derived peptide hormone CCHamide-2 (CCHa2 acts as a nutrient-dependent regulator of Drosophila insulin-like peptides (Dilps. A BAC-based transgenic reporter revealed strong expression of CCHa2 receptor (CCHa2-R in insulin-producing cells (IPCs in the brain. Calcium imaging of brain explants and IPC-specific CCHa2-R knockdown demonstrated that peripheral-tissue derived CCHa2 directly activates IPCs. Interestingly, genetic disruption of either CCHa2 or CCHa2-R caused almost identical defects in larval growth and developmental timing. Consistent with these phenotypes, the expression of dilp5, and the release of both Dilp2 and Dilp5, were severely reduced. Furthermore, transcription of CCHa2 is altered in response to nutritional levels, particularly of glucose. These findings demonstrate that CCHa2 and CCHa2-R form a direct link between peripheral tissues and the brain, and that this pathway is essential for the coordination of systemic growth with nutritional availability. A mammalian homologue of CCHa2-R, Bombesin receptor subtype-3 (Brs3, is an orphan receptor that is expressed in the islet β-cells; however, the role of Brs3 in insulin regulation remains elusive. Our genetic approach in Drosophila melanogaster provides the first evidence, to our knowledge, that bombesin receptor signaling with its endogenous ligand promotes insulin production.

  19. Neurotransmitters and putative neuromodulators in the gut of Anguilla anguilla (L.. Localizations in the enteric nervous and endocrine systems

    Directory of Open Access Journals (Sweden)

    A Veggetti

    2009-12-01

    Full Text Available The gut of silver eels (Anguilla anguilla L. was investigated in order to describe both the cholinergic and adrenergic intramural innervations, and the localization of possible accessory neuromediators. Histochemical reactions for the demonstration of nicotinamide adenine dinucleotide phosphate, reduced form-(NADPH-diaphorase and acetylcholinesterese (AChEase were performed, as well as the immunohistochemical testing of tyrosine hydroxylase, met-enkephalin, substance P, calcitonin gene-related peptide (CGRP, bombesin, vasoactive intestinal peptide (VIP, neuropeptide Y (NPY, somatostatin, cholecystokinin-octapeptide (CCK-8, serotonin, cholineacetyltransferase. The results evidenced a different pattern in comparison with other vertebrates, namely mammals, and with other fish. Both NADPH-diaphorase and AChEase activities were histochemically detected all along the gut in the myenteric plexus, the inner musculature and the propria-submucosa. Tyrosine hydroxylase immunoreactivity was observed in the intestinal tract only, both in the myenteric plexus and in the inner musculature. Several neuropeptides (metenkephalin, CGRP, bombesin, substance P, VIP, NPY, somatostatin were, in addition, detected in the intramural innervation; some of them also in epithelial cells of the diffuse endocrine system (met-enkephalin, substance P, NPY, somatostatin. Serotonin was only present in endocrine cells. Tyrosine hydroxylase immunoreactivity was present in localizations to those of similar NADPHdiaphorase- reactivity, and in the same nerve bundles in which substance P- and CGRP-likeimmunoreactivities were detectable in the intestinal tract. In addition, NADPH-diaphorase-reactive neurons showed an anatomical relationship with AChEase-reactive nerve terminals, and a similar relationship existed between the latter and substance P-like immunoreactivity.

  20. Diagnostic criteria and follow-up in neuroendocrine cell hyperplasia of infancy: a case series

    Directory of Open Access Journals (Sweden)

    Vivianne Calheiros Chaves Gomes

    2013-09-01

    Full Text Available OBJECTIVE: Neuroendocrine cell hyperplasia of infancy (NEHI is a form of childhood interstitial lung disease characterized by tachypnea, retractions, crackles, and hypoxia. The aim of this study was to report and discuss the clinical, imaging, and histopathological findings in a series of NEHI cases at a tertiary pediatric hospital, with an emphasis on diagnostic criteria and clinical outcomes. METHODS: Between 2003 and 2011, 12 full-term infants were diagnosed with NEHI, based on clinical and tomographic findings. Those infants were followed for 1-91 months. Four infants were biopsied, and the histopathological specimens were stained with bombesin antibody. RESULTS: In this case series, symptoms appeared at birth in 6 infants and by 3 months of age in the remaining 6. In all of the cases, NEHI was associated with acute respiratory infection. The most common initial chest HRCT findings were ground-glass opacities that were in the middle lobe/lingula in 12 patients and in other medullary areas in 10. Air trapping was the second most common finding, being observed in 7 patients. Follow-up HRCT scans (performed in 10 patients revealed normal results in 1 patient and improvement in 9. The biopsy findings were nonspecific, and the staining was positive for bombesin in all samples. Confirmation of NEHI was primarily based on clinical and tomographic findings. Symptoms improved during the follow-up period (mean, 41 months. A clinical cure was achieved in 4 patients. CONCLUSIONS: In this sample of patients, the diagnosis of NEHI was made on the basis of the clinical and tomographic findings, independent of the lung biopsy results. Most of the patients showed clinical improvement and persistent tomographic changes during the follow-up period, regardless of the initial severity of the disease or type of treatment.

  1. Radiolabelled peptides for tumour therapy: current status and future directions. Plenary lecture at the EANM 2002

    Energy Technology Data Exchange (ETDEWEB)

    Jong, Marion de; Kwekkeboom, Dik; Valkema, Roelf; Krenning, Eric P. [Department of Nuclear Medicine, L2, Erasmus MC, 3015 GD, Rotterdam (Netherlands)

    2003-03-01

    On their plasma membranes, cells express receptor proteins with high affinity for regulatory peptides, such as somatostatin. Changes in the density of these receptors during disease, e.g. overexpression in many tumours, provide the basis for new imaging methods. The first peptide analogues successfully applied for visualisation of receptor-positive tumours were radiolabelled somatostatin analogues. The next step was to label these analogues with therapeutic radionuclides for peptide receptor radionuclide therapy (PRRT). Results from preclinical and clinical multicentre studies have already shown an effective therapeutic response when using radiolabelled somatostatin analogues to treat receptor-positive tumours. Infusion of positively charged amino acids reduces kidney uptake, enlarging the therapeutic window. For PRRT of CCK-B receptor-positive tumours, such as medullary thyroid carcinoma, radiolabelled minigastrin analogues are currently being successfully applied. The combination of different therapy modalities holds interest as a means of improving the clinical therapeutic effects of radiolabelled peptides. The combination of different radionuclides, such as {sup 177}Lu- and {sup 90}Y-labelled somatostatin analogues, to reach a wider tumour region of high curability, has been described. A variety of other peptide-based radioligands, such as bombesin and NPY(Y{sub 1}) analogues, receptors for which are expressed on common cancers such as prostate and breast cancer, are currently under development and in different phases of (pre)clinical investigation. Multi-receptor tumour targeting using the combination of bombesin and NPY(Y{sub 1}) analogues is promising for scintigraphy and PRRT of breast carcinomas and their lymph node metastases. (orig.)

  2. Preparation of the radiopharmaceutical {sup 99m} Tc-HYNIC-[Lys{sup 3}]-BN; Preparacion del radiofarmaco {sup 99m} Tc-HYNIC-[Lys{sup 3}]-BN

    Energy Technology Data Exchange (ETDEWEB)

    Conde S, E. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, 50000 Toluca, Estado de Mexico (Mexico)

    2007-07-01

    In accordance with their design, the radiopharmaceuticals can be divided in three generations. The radiopharmaceuticals of third generation are used in nuclear medicine to obtain images of specific molecular targets, and they are only in their capacity to detect in vivo such specific biochemical places as receivers and enzymes. The receivers of regulator peptides are over expressed in numerous carcinogenic cells. Those receivers have been used as molecular targets of radiolabelled peptides to locate cancerous tumors. The small peptide bombesin (BN, 14 amino acids) it was isolated of the frog skin and it belongs to a wide neuropeptides group with many biological functions. The equivalent human is the liberator peptide of the gastrin (GRP, 27 amino acids) and his receivers (r-GRP) that are on expressed in the membranes of the tumor cells. The receiving subtype 2 of bombesin (receiving GRP) it is on expressed in several human tumors including breast, prostate, lung cells and pancreatic cancer. Some radiopharmaceuticals similar of BN has been developed that were prepared to be used in nuclear medicine for the detection of wicked tumors and to evidence prostate cancers, breast and of lymphatic nodules. A technique was developed to allow the conjugation of HYNIC-[Lys3]-BN that allowed to obtain this product with a high purity. The identity was determined by HPLC chromatography. It was necessary the validation of the method and the HPLC system, to assure that the results were reliable. Linearity, specificity, accuracy and precision parameters were analyzed, that are those required by the Mexican pharmacopoeia for chromatographic methods. With this conjugated a formulation for lyophilized kits were analyzed, with the purpose of obtaining a radiochemical purity, after the labelled one with {sup 99m}Tc, bigger to 95%; the components used in the nucleus-equipment should favor the conjugation of the {sup 99m}Tc by means of a ligands exchange between the tricine and the

  3. Preparation of the radiopharmaceutical 99m Tc-HYNIC-[Lys3]-BN

    International Nuclear Information System (INIS)

    In accordance with their design, the radiopharmaceuticals can be divided in three generations. The radiopharmaceuticals of third generation are used in nuclear medicine to obtain images of specific molecular targets, and they are only in their capacity to detect in vivo such specific biochemical places as receivers and enzymes. The receivers of regulator peptides are over expressed in numerous carcinogenic cells. Those receivers have been used as molecular targets of radiolabelled peptides to locate cancerous tumors. The small peptide bombesin (BN, 14 amino acids) it was isolated of the frog skin and it belongs to a wide neuropeptides group with many biological functions. The equivalent human is the liberator peptide of the gastrin (GRP, 27 amino acids) and his receivers (r-GRP) that are on expressed in the membranes of the tumor cells. The receiving subtype 2 of bombesin (receiving GRP) it is on expressed in several human tumors including breast, prostate, lung cells and pancreatic cancer. Some radiopharmaceuticals similar of BN has been developed that were prepared to be used in nuclear medicine for the detection of wicked tumors and to evidence prostate cancers, breast and of lymphatic nodules. A technique was developed to allow the conjugation of HYNIC-[Lys3]-BN that allowed to obtain this product with a high purity. The identity was determined by HPLC chromatography. It was necessary the validation of the method and the HPLC system, to assure that the results were reliable. Linearity, specificity, accuracy and precision parameters were analyzed, that are those required by the Mexican pharmacopoeia for chromatographic methods. With this conjugated a formulation for lyophilized kits were analyzed, with the purpose of obtaining a radiochemical purity, after the labelled one with 99mTc, bigger to 95%; the components used in the nucleus-equipment should favor the conjugation of the 99mTc by means of a ligands exchange between the tricine and the

  4. Calculus of spatial distribution of absorbed dose to cellular level by Monte Carlo simulation for a radio-labelled peptide with {sup 188}Re and with nuclear internalization : preliminary results; Calculo de la distribucion espacial de dosis absorbida a nivel celular por simulacion Monte Carlo para un peptido radiomarcado con {sup 188}Re y con internalizacion nuclear : resultados preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E. L. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Santos C, C. L. [Universidad Autonoma del Estado de Mexico, Paseo Tollocan y Jesus Carranza, Toluca 50120, Estado de Mexico (Mexico)], e-mail: leticia.rojas@inin.gob.mx

    2009-10-15

    The {sup 188}Re is a radionuclide of radiation gamma emitter, useful in obtaining of gamma-graphic images, but it is also emitter of beta radiations and Auger electrons. A bio-molecule directed to a specific receptor of a cancer cell labeled with a emitter radionuclide of beta particles and Auger electrons, as the {sup 188}Re-Tat-Bombesin, it has the potential to be used in radiotherapy of molecular targets for its capacity to penetrate to cellular nucleus. In this system, the radiation dose is distributed in way located at microscopic levels in sub cellular specific places, where Auger emissions contributes of significant way in absorbed dose. The cellular dosimetry is realized in most of cases, using analytic or semi analytical methods, for example the cellular MIRD methodology. However, it is required to complement these calculations simulating the electrons transport and considering experimental bio kinetics data. Therefore, in this work preliminary results are presented of dosimetric calculation to sub cellular level for {sup 188}Re-Tat-Bombesin by Monte Carlo simulation, using the 2008 version of PENELOPE: PENEASY code. The spatial distribution of absorbed dose in membrane, cytoplasm and nucleus, was calculated with geometry of a cell of 10 {mu}m of diameter, a nucleus of 2 {mu}m of ratio and membrane of 0.2 {mu}m of thickness, considering elementary constitution for each cellular compartment proposal in literature. The total number of disintegrations at sub cellular level was evaluated integrating the activity in function of time starting from experimental bio kinetics data in mamma cancer cells MDA-MB231. The preliminary results show that 46.4% of total disintegrations for unit of captured activity by cell occurs in nucleus, 38.4% in membrane and 15.2% in cytoplasm. The due absorbed dose to Auger electrons for 1 Bq of {sup 188}Re located in cellular membrane were respectively of 1.32E-1 and 1.43E-1 Gy in cytoplasm and nucleus. (Author)

  5. Frequency Domain Fluorescent Molecular Tomography and Molecular Probes for Small Animal Imaging

    Science.gov (United States)

    Kujala, Naresh Gandhi

    Fluorescent molecular tomography (FMT) is a noninvasive biomedical optical imaging that enables 3-dimensional quantitative determination of fluorochromes distributed in biological tissues. There are three methods for imaging large volume tissues based on different light sources: (a) using a light source of constant intensity, through a continuous or constant wave, (b) using a light source that is intensity modulated with a radio frequency (RF), and (c) using ultrafast pulses in the femtosecond range. In this study, we have developed a frequency domain fluorescent molecular tomographic system based on the heterodyne technique, using a single source and detector pair that can be used for small animal imaging. In our system, the intensity of the laser source is modulated with a RF frequency to produce a diffuse photon density wave in the tissue. The phase of the diffuse photon density wave is measured by comparing the reference signal with the signal from the tissue using a phasemeter. The data acquisition was performed by using a Labview program. The results suggest that we can measure the phase change from the heterogeneous inside tissue. Combined with fiber optics and filter sets, the system can be used to sensitively image the targeted fluorescent molecular probes, allowing the detection of cancer at an early stage. We used the system to detect the tumor-targeting molecular probe Alexa Fluor 680 and Alexa Fluor 750 bombesin peptide conjugates in phantoms as well as mouse tissues. We also developed and evaluated fluorescent Bombesin (BBN) probes to target gastrin-releasing peptide (GRP) receptors for optical molecular imaging. GRP receptors are over-expressed in several types of human cancer cells, including breast, prostate, small cell lung, and pancreatic cancers. BBN is a 14 amino acid peptide that is an analogue to human gastrin-releasing peptide that binds specifically to GRPr receptors. BBN conjugates are significant in cancer detection and therapy. The

  6. Molecular basis for high affinity and selectivity of peptide antagonist, Bantag-1, for the orphan BB3 receptor.

    Science.gov (United States)

    Nakamura, Taichi; Ramos-Álvarez, Irene; Iordanskaia, Tatiana; Moreno, Paola; Mantey, Samuel A; Jensen, R T

    2016-09-01

    Bombesin-receptor-subtype-3 (BB3 receptor) is a G-protein-coupled-orphan-receptor classified in the mammalian Bombesin-family because of high homology to gastrin-releasing peptide (BB2 receptor)/neuromedin-B receptors (BB1 receptor). There is increased interest in BB3 receptor because studies primarily from knockout-mice suggest it plays roles in energy/glucose metabolism, insulin-secretion, as well as motility and tumor-growth. Investigations into its roles in physiological/pathophysiological processes are limited because of lack of selective ligands. Recently, a selective, peptide-antagonist, Bantag-1, was described. However, because BB3 receptor has low-affinity for all natural, Bn-related peptides, little is known of the molecular basis of its high-affinity/selectivity. This was systematically investigated in this study for Bantag-1 using a chimeric-approach making both Bantag-1 loss-/gain-of-affinity-chimeras, by exchanging extracellular (EC) domains of BB3/BB2 receptor, and using site-directed-mutagenesis. Receptors were transiently expressed and affinities determined by binding studies. Bantag-1 had >5000-fold selectivity for BB3 receptor over BB2/BB1 receptors and substitution of the first EC-domain (EC1) in loss-/gain-of affinity-chimeras greatly affected affinity. Mutagenesis of each amino acid difference in EC1 between BB3 receptor/BB2 receptor showed replacement of His(107) in BB3 receptor by Lys(107) (H107K-BB3 receptor-mutant) from BB2 receptor, decreased affinity 60-fold, and three replacements [H107K, E11D, G112R] decreased affinity 500-fold. Mutagenesis in EC1's surrounding transmembrane-regions (TMs) demonstrated TM2 differences were not important, but R127Q in TM3 alone decreased affinity 400-fold. Additional mutants in EC1/TM3 explored the molecular basis for these changes demonstrated in EC1, particularly important is the presence of aromatic-interactions by His(107), rather than hydrogen-bonding or charge-charge interactions, for determining

  7. Expression of feeding-related peptide receptors mRNA in GT1-7 cell line and roles of leptin and orexins in control of GnRH secretion

    Institute of Scientific and Technical Information of China (English)

    Ying YANG; Li-bin ZHOU; Shang-quan LIU; Jing-feng TANG; Feng-yin LI; Rong-ying LI; Huai-dong SONG; Ming-dao CHEN

    2005-01-01

    Aim: To investigate the expression of feeding-related peptide receptors mRNA in GT1-7 cell line and roles of leptin and orexins in the control of GnRH secretion.Methods: Receptors of bombesin3, cholecystokinin (CCK)-A, CCK-B, glucagonlike peptide (GLP)1, melanin-concentrating hormone (MCH)1, orexinl, orexin2,neuromedin-B, neuropeptide Y (NPY) 1 and NPY5, neurotensin (NT) 1, NT2, NT3,and leptin receptor long form mRNA in GT1-7 cells were detected by reversed transcriptase-polymerase chain reaction. GT1-7 cells were treated with leptin,orexin A and orexin B at a cohort of concentrations for different lengths of time,and GnRH in medium was determined by radioimmunoassay (RIA). Results:Receptors of bombesin 3, CCK-B, GLP1, MCH1, orexinl, neuromedin-B, NPY1,NPY5, NT1, NT3, and leptin receptor long form mRNA were expressed in GT1-7cells, of which, receptors of GLP1, neuromedin-B, NPY1, and NT3 were highly expressed. No amplified fragments of orexin2, NT2, and CCK-A receptor cDNA were generated with GT1-7 RNA, indicating that the GT1-7 cells did not express mRNA of them. Leptin induced a significant stimulation of GnRH release, the results being most significant at 0.1 nmol/L for 15 min. In contrast to other studies in hypothalamic explants, neither orexin A nor orexin B affected basal GnRH secretion over a wide range of concentrations ranging from 1 nmol/L to 500 nmol/Lat 15, 30, and 60 min. Conclusion: Feeding and reproductive function are closely linked. Many orexigenic and anorexigenic signals may control feeding behavior as well as alter GnRH secretion through their receptors on GnRH neurons.

  8. 胃泌素释放肽在炎性疾病中的作用%Roles of gastrin-releasing peptide in inflammatory diseases

    Institute of Scientific and Technical Information of China (English)

    郭龙; 阮林星; 李金宝

    2016-01-01

    Background Gastrin-releasing peptide (GRP), a neuropeptide, belongs to the bombesin (BB) and is expressed in various organs (such as gastrointestinal system, respiratory system, nervous system, endocrine gland and skeletal muscles).Gastrin-releasing peptide receptors (GRPR) is a kind of G protein coupled receptors (GPCRs).In recent years, more and more studies have focused on potential roles of GRP in inflammatory diseases.RC-3095, as a specific GRPR antagonist, has been found to have antiinflammatory properties.Objective To investigate the potential roles and research situation of GRP-GRPR in inflammatory diseases.Content Mainly focusing on reviewing sepsis, arthritis, gastroenteritis, and uveitis, we summarized the roles of GRP-GRPR in inflammatory diseases.Trend In conclusion, GRP and its receptor is a potential therapeutic target in inflammatory diseases as well as the possible transformation from preclinical findings to clinical application.%背景 胃泌素释放肽(gastrin-releasing peptide,GRP)是一种神经肽,属于铃蟾肽类(bombesin,BB),表达于多种组织(胃肠系统、呼吸系统、神经系统、内分泌腺以及骨骼肌等).胃泌素释放肽受体(gastrin-releasing peptide receptor,GRPR)属于G蛋白耦联受体(G protein coupled receptors,GPCRs).近年来,GRP在炎症性疾病中的作用备受关注,研究显示RC-3095作为GRPR特异性拮抗剂具有抗炎作用.目的 探讨GRP在炎性疾病中的作用及其研究现状.内容 主要从脓毒症、关节炎、胃肠炎、眼葡萄膜炎等炎性疾病着手,对GRP在炎症疾病中的作用进行归纳总结.趋向 GRP-GRPR将有可能成为炎性疾病的潜在治疗靶点,并有望实现从基础研究到临床应用的转化.

  9. Paul Scherrer Institut Scientific Report 2001. Volume II: Life Sciences

    Energy Technology Data Exchange (ETDEWEB)

    Jaussi, R.; Gschwend, B. (eds.)

    2002-03-01

    The IMR group investigated some new approaches to tumour therapy. Several candidate molecules for targeting the tumour vasculature have been identified and are being produced for in vivo studies in tumour-bearing mice. The liposome technology is well established in this group and the goal is to produce suitably tagged liposomes for delivering a variety of cytotoxic agents to tumours. The Centre for Radiopharmaceutical Science, a joint venture with the ETH Zurich and the University of Zurich, pursues a number of projects that should eventually lead to novel radiopharmaceuticals for tumour diagnosis and therapy. Functionally, these radioactive drugs consist of a tumour targeting part, a radionuclide and a linking moiety, which stably connects the two. Optimisation of the components and their combination in terms of in vitro and in vivo properties as well as the efficient large-scale production of promising candidates for eventual first clinical trials is a demanding task. The major emphasis is still on using antibodies, antibody derivatives or peptides as tumour targeting vehicles. In collaboration with the Queens Medical Centre Nottingham, the first patients were treated with a {sup 67}Cu labelled antibody targeting bladder carcinomas. When completed, these studies should give us important information on the usefulness of {sup 67}Cu as a therapeutic radionuclide. Neuropeptides such as neurotensin and bombesin are promising starting points for tumour targeting as their receptors are over expressed on certain tumour cells. Presently, the efforts concentrate on preparing for further clinical studies with neurotensin derivatives (diagnosis of pancreatic tumours using {sup 99m}Tc) and further improving the stability and pharmacological properties of bombesin derivatives. In both these projects the ultimate goal is to label the optimised compounds with {sup 186}Re, a therapeutic radionuclide that can be attached in the stable tricarbonyl form which is easily accessible by

  10. Gastrin-releasing peptide is a transmitter mediating porcine gallbladder contraction

    DEFF Research Database (Denmark)

    Schjoldager, Birgit; Poulsen, S.S.; Schmidt, P.;

    1991-01-01

    We studied the role of gastrin-releasing peptide (GRP) for porcine gallbladder motility. Immunohistochemistry visualized nerve fibers containing GRP-like immunoreactivity in muscularis. GRP concentration dependently stimulated contractions of muscularis strips (ED50, 2.9 nM). Neuromedin B was less...... potent (ED50, 0.1 microM), suggesting existence of GRP-preferring receptors. GRP-induced contractions were unaffected by muscarinic antagonism (1 microM atropine), axonal blockade (1 microM tetrodotoxin), cholecystokinin (CCK) receptor antagonism (10 microM MK-329), or substance P desensitization (1...... microM), supporting the existence of myogenic GRP receptors. The bombesin (BN) analogue D-Phe6-BN-(6-13)propylamide (PA) stimulated contractions (ED50, 3.3 nM) with low efficacy (29% of that of GRP). D-Phe6-BN-(6-13)PA (1 microM) shifted GRP concentration-response curves one log to the right. D-Phe6-BN...

  11. Capillary zone electrophoresis analysis and detection of mid-spectrum biological warfare agents

    Energy Technology Data Exchange (ETDEWEB)

    Boulet, C.A.; Townsley, C.

    1995-04-01

    DRE Suffield has initiated a research program to develop methods and equipment for field detection and laboratory identification of mid-spectrum agents, molecules of biological origin such as proteins, peptides and toxins. In this study, a highly efficient and reproducible capillary zone electrophoresis method was developed to separate and identify a series of nine peptides of defence interest: bradykinin, bradykinin fragment 1-5, substance P,ARG8-vasopressin, luteinizing hormone releasing hormone, bombesin, leucine enkephalin, methionine enkephalin, and oxytocin. Using a 50 micrometer x 47 cm capillary column, 22.5 kV separation voltage and a 100 mM pH 2.5 phosphate buffer, all nine peptide could separated in under 10 minutes. Three strategies, which could be used in a fully automated field detection and identification system, were demonstrated for the identification of unknown peptides: comparison of migration times, comparison of electrophoretic mobilities, and co-injection of multiple reference standards. These experiments demonstrate that a separation based analytical method such as capillary electrophoresis could form the basis of a generic detection system for mid-spectrum protein and peptide toxins.

  12. Regulatory peptides in the upper respiratory system and oral cavity of man. An immunocytochemical and radioimmunological study

    International Nuclear Information System (INIS)

    In the present study a dense network of peptide-immunoreactive nerve fibres in the upper respiratory system and the oral cavity of man was investigated. The occurrence, distribution and concentrations of regulatory peptide immunoreactivities in human nasal mucosa, soft palate, ventricular fold, vocal cord, epiglottis, subglottis, glandula submandibularis and glandula parotis were investigated using highly efficient immunocytochemical and radio-immunological methods. In the tissues investigated vasoactive intestinal polypeptide (VIP) and other derivatives from the VIP-precursor (peptide histidine methionine = PHM), prepro VIP (111-122)), neuropeptide tyrosine (NPY) and its C-flanking peptide (CPON), calcitonin gene-related peptide (CGRP), substance P, neurokinin A, bombesin-flanking peptide and somatostatin were detected. The regulatory peptides demonstrated also included the recently isolated peptides helospectin and pituitary adenylate cyclase activating peptide (PACAP). Single endocrine-like cells were for the first time demonstrated within the respiratory epithelium and in the lamina propria of the nasal mucosa and soft palate and in groups within ducts. Ultrastructural immunelectronmicroscopy was performed using an ABC-pre-embedding method. In addition, semithin Epon resin sections were immunostained. The concentrations of VIP, NPY, CGRP, substance P and neurokinin A were measured using radioimmunological methods. The peptide immunoreactivities demonstrated in a dense network of neuronal structures and endocrine cells give indication for the presence of a complex regulatory system with potent physiological mechanisms in the upper respiratory system and allocated tissues of man

  13. Automated synthesis, characterization and biological evaluation of [{sup 68}Ga]Ga-AMBA, and the synthesis and characterization of {sup nat}Ga-AMBA and [{sup 67}Ga]Ga-AMBA

    Energy Technology Data Exchange (ETDEWEB)

    Cagnolini, Aldo; Chen Jianqing; Ramos, Kimberly; Marie Skedzielewski, Tina; Lantry, Laura E.; Nunn, Adrian D.; Swenson, Rolf E. [Ernst Felder Laboratories, Bracco Research USA Inc., 305 College Road East, Princeton, NJ 08540 (United States); Linder, Karen E., E-mail: karen.e.linder@gmail.co [Ernst Felder Laboratories, Bracco Research USA Inc., 305 College Road East, Princeton, NJ 08540 (United States)

    2010-12-15

    Ga-AMBA (Ga-DO3A-CH{sub 2}CO-G-[4-aminobenzoyl]-QWAVGHLM-NH{sub 2}) is a bombesin-like agonist with high affinity for gastrin releasing peptide receptors (GRP-R). Syntheses for {sup nat}Ga-AMBA, [{sup 67}Ga]Ga-AMBA and [{sup 68}Ga]Ga-AMBA were developed. The preparation of HPLC-purified and Sep-Pak purified [{sup 68}Ga]Ga-AMBA were fully automated, using the built-in radiodetector of the Tracerlab FX F-N synthesizer to monitor fractionated {sup 68}Ge/{sup 68}Ga generator elution and purification. The total synthesis time, including the fractional elution of the generator, was 20 min for Sep-Pak purified material and 40 min for HPLC-purified [{sup 68}Ga]Ga-AMBA. Both [{sup 67}Ga]Ga-AMBA and [{sup 177}Lu]Lu-AMBA showed comparable high affinity for GRP-R in the human prostate cancer cell line PC-3 in vitro (k{sub D}=0.46{+-}0.07; 0.44{+-}0.08 nM), high internalization (78; 77%) and low efflux from cells at 2 h (2.4{+-}0.7; 2.9{+-}1.8%). Biodistribution results in PC-3 tumor-bearing male nude mice showed comparable uptake for [{sup 177}Lu]Lu-, [{sup 111}In]In-, [{sup 67}Ga]Ga- and [{sup 68}Ga]Ga-AMBA.

  14. Genetic induction of the gastrin releasing peptide receptor on tumor cells for radiolabeled peptide binding

    International Nuclear Information System (INIS)

    Purpose/Objective: To improve upon existing radioimmunotherapy (RAIT) approaches, we have devised a strategy to genetically induce high levels of new membrane-associated receptors on human cancer cells targetable by radiolabeled peptides. In this context, we report successful adenoviral-mediated transduction of tumor cells to express the murine gastrin releasing peptide receptor (mGRPr) as demonstrated by125 I-labeled bombesin binding. Materials and Methods: To demonstrate the feasibility of our strategy and to provide rapid proof of principle, we constructed a plasmid encoding the mGRPr gene. We cloned the mGRPr gene into the adenoviral shuttle vector pACMVpLpARS+ (F. Graham). We then utilized the methodology of adenovirus-polylysine-mediated transfection (AdpLmGRPr) to accomplish transient gene expression of mGRPr in two human cancer cell lines including A427 non-small cell lung cancer cells and HeLa cervical cancer cells. Murine GRPr expression was then measured by a live-cell binding assay using 125I-labeled bombesin. In order to develop this strategy further, it was necessary to construct a vector that would be more efficient for in vivo transduction. In this regard, we constructed a recombinant adenoviral vector (AdCMVGRPr) encoding the mGRPr under the control of the CMV promoter based on in vivo homologous recombination methods. The recombinant shuttle vector containing mGRPr was co-transfected with the adenoviral rescue plasmid pJM17 into the E1A trans complementing cell line 293 allowing for derivation of replication-incompetent, recombinant adenoviral vector. Individual plaques were isolated and subjected to two further rounds of plaque purification. The identity of the virus was confirmed at each step by PCR employing primers for mGRPr. The absence of wild-type adenovirus was confirmed by PCR using primers to the adenoviral E1A gene. SKOV3.ip1 human ovarian cancer cells and MDA-MB-231 human breast cancer cells were transduced in vitro with AdCMVGRPr at

  15. Obese and lean Zucker rats respond similarly to intraperitoneal administration of gastrin-releasing peptides.

    Science.gov (United States)

    Washington, Martha C; Park, Karen H; Sayegh, Ayman I

    2014-08-01

    The Zucker rat is an animal model used to study obesity and the control of food intake by various satiety peptides. The amphibian peptide bombesin (Bn) reduces cumulative food intake similarly in both obese and lean weanling Zucker rats. Here, we hypothesized that intraperitoneal (i.p) administration of gastrin-releasing peptides-10, -27 and -29 (GRP-10, GRP-27, GRP-29), which are the mammalian forms of Bn, would reduce first meal size (MS, 10% sucrose) and prolong the intermeal interval (IMI, time between first and second meals) similarly in obese and lean adult Zucker rats. To test this hypothesis, we administered GRP-10, GRP-27 and GRP-29 (0, 2.1, 4.1 and 10.3 nmol/kg) i.p. to obese and lean male Zucker rats (who were deprived of overnight food but not water) and then measured the first and second MS, IMI and satiety ratio (SR, IMI/MS). We found that in both obese and lean rats, all forms of GRP reduced the first MS, and in lean rats, they also decreased the second MS. Additionally, GRP-10 and GRP-29 prolonged the IMI in both obese and lean rats, but GRP-27 only prolonged it in lean rats. Finally, we found that all forms of GRP increased the SR in both obese and lean rats. In agreement with our hypothesis, we conclude that all forms of GRP reduce food intake in obese and lean adult Zucker rats similar to Bn in weanling rats.

  16. Gastrin-releasing peptide stimulates glycoconjugate release from feline trachea

    International Nuclear Information System (INIS)

    The effect of gastrin-releasing peptide (GRP) on respiratory glycoconjugate (RGC) secretion was investigated in a feline tracheal organ culture model. RGC secretion was stimulated by GRP in a dose-dependent fashion at concentrations from 10(-8) to 10(-5) M (range 15-38% increase above control) with a peak effect within 0.5-1 h of incubation. GRP-(14-27), the receptor binding portion of GRP, and the related molecule, bombesin, also stimulated RGC secretion by approximately 20% above control. Acetyl-GRP-(20-27) stimulated RGC release by 10%, whereas GRP-(1-16) was inactive. Autoradiographic studies with 125I-GRP revealed that specific binding was restricted to the submucosal glands and the surface epithelium. A specific radioimmunoassay showed the content of GRP in feline trachea after extraction with ethanol-acetic acid to be 156 +/- 91 fmol/g wet wt. Indirect immunohistochemistry indicated that ganglion cells located just outside the cartilage contained GRP-immunoreactive materials. GRP is a novel mucus secretagogue that may participate in regulating airway mucosal gland secretion

  17. D-Arg1,D-Phe5,D-Trp7,9,Leu11 substance P, a neuropeptide antagonist, blocks binding, Ca2(+)-mobilizing, and mitogenic effects of endothelin and vasoactive intestinal contractor in mouse 3T3 cells

    International Nuclear Information System (INIS)

    Endothelin (ET1) and vasoactive intestinal contractor (VIC) stimulate quiescent Swiss 3T3 cells to resume DNA synthesis acting synergistically with epidermal growth factors (EGF) and other mitogens. The peptide [D-Arg1,D-Phe5,D-Trp7,9,Leu11] substance P has been identified as a broad spectrum neuropeptide antagonist which blocks the binding and biological effects of the Ca2(+)-mobilizing neuropeptides bombesin, vasopressin, and bradykinin. In the present study we show that [D-Arg1,D-Phe5,D-Trp7,9,Leu11] substance P also acts as an ET1/VIC antagonist as judged by the following criteria: (a) inhibition of specific 125I-labelled ET1 binding to a ET1/VIC receptor in a competitive and dose-dependent manner; (b) blocking of the rapid increase in the cytosolic Ca2+ concentration promoted by ET1 or VIC; and (c) inhibition of DNA synthesis stimulated by VIC in the presence of EGF. The inhibitory effects of [D-Arg1,D-Phe5,D-Trp7,9,Leu 11] substance P on Ca2+ mobilization and DNA synthesis were reversed by increasing the concentration of VIC. This is the first time that a peptide structurally unrelated to ET1 or VIC is shown to block the binding and mitogenic effects of peptides of the endothelin family

  18. The next generation of positron emission tomography radiopharmaceuticals in oncology.

    Science.gov (United States)

    Rice, Samuel L; Roney, Celeste A; Daumar, Pierre; Lewis, Jason S

    2011-07-01

    Although (18)F-fluorodeoxyglucose ((18)F-FDG) is still the most widely used positron emission tomography (PET) radiotracer, there are a few well-known limitations to its use. The last decade has seen the development of new PET probes for in vivo visualization of specific molecular targets, along with important technical advances in the production of positron-emitting radionuclides and their related labeling methods. As such, a broad range of new PET tracers are in preclinical development or have recently entered clinical trials. The topics covered in this review include labeling methods, biological targets, and the most recent preclinical or clinical data of some of the next generation of PET radiopharmaceuticals. This review, which is by no means exhaustive, has been separated into sections related to the PET radionuclide used for radiolabeling: fluorine-18, for the labeling of agents such as FACBC, FDHT, choline, and Galacto-RGD; carbon-11, for the labeling of choline; gallium-68, for the labeling of peptides such as DOTATOC and bombesin analogs; and the long-lived radionuclides iodine-124 and zirconium-89 for the labeling of monoclonal antibodies cG250, and J591 and trastuzumab, respectively.

  19. Bacterial mimetics of endocrine secretory granules as immobilized in vivo depots for functional protein drugs

    Science.gov (United States)

    Céspedes, María Virtudes; Fernández, Yolanda; Unzueta, Ugutz; Mendoza, Rosa; Seras-Franzoso, Joaquin; Sánchez-Chardi, Alejando; Álamo, Patricia; Toledo-Rubio, Verónica; Ferrer-Miralles, Neus; Vázquez, Esther; Schwartz, Simó; Abasolo, Ibane; Corchero, José Luis; Mangues, Ramon; Villaverde, Antonio

    2016-01-01

    In the human endocrine system many protein hormones including urotensin, glucagon, obestatin, bombesin and secretin, among others, are supplied from amyloidal secretory granules. These granules form part of the so called functional amyloids, which within the whole aggregome appear to be more abundant than formerly believed. Bacterial inclusion bodies (IBs) are non-toxic, nanostructured functional amyloids whose biological fabrication can be tailored to render materials with defined biophysical properties. Since under physiological conditions they steadily release their building block protein in a soluble and functional form, IBs are considered as mimetics of endocrine secretory granules. We have explored here if the in vivo implantation of functional IBs in a given tissue would represent a stable local source of functional protein. Upon intratumoral injection of bacterial IBs formed by a potent protein ligand of CXCR4 we have observed high stability and prevalence of the material in absence of toxicity, accompanied by apoptosis of CXCR4+ cells and tumor ablation. Then, the local immobilization of bacterial amyloids formed by therapeutic proteins in tumors or other tissues might represent a promising strategy for a sustained local delivery of protein drugs by mimicking the functional amyloidal architecture of the mammals’ endocrine system. PMID:27775083

  20. Identification of Miscellaneous Peptides from the Skin Secretion of the European Edible Frog, Pelophylax kl. Esculentus.

    Science.gov (United States)

    Chen, Xiaole; Wang, He; Wang, Lei; Zhou, Mei; Chen, Tianbao; Shaw, Chris

    2016-08-01

    The chemical compounds synthesised and secreted from the dermal glands of amphibian have diverse bioactivities that play key roles in the hosts' innate immune system and in causing diverse pharmacological effects in predators that may ingest the defensive skin secretions. As new biotechnological methods have developed, increasing numbers of novel peptides with novel activities have been discovered from this source of natural compounds. In this study, a number of defensive skin secretion peptide sequences were obtained from the European edible frog, P. kl. esculentus, using a 'shotgun' cloning technique developed previously within our laboratory. Some of these sequences have been previously reported but had either obtained from other species or were isolated using different methods. Two new skin peptides are described here for the first time. Esculentin-2c and Brevinin-2Tbe belong to the Esculentin-2 and Brevinin-2 families, respectively, and both are very similar to their respective analogues but with a few amino acid differences. Further, [Asn-3, Lys-6, Phe-13] 3-14-bombesin isolated previously from the skin of the marsh frog, Rana ridibunda, was identified here in the skin of P. kl. esculentus. Studies such as this can provide a rapid elucidation of peptide and corresponding DNA sequences from unstudied species of frogs and can rapidly provide a basis for related scientific studies such as those involved in systematic or the evolution of a large diverse gene family and usage by biomedical researchers as a source of potential novel drug leads or pharmacological agents. PMID:27402449

  1. D-Arg1,D-Phe5,D-Trp7,9,Leu11 substance P, a neuropeptide antagonist, blocks binding, Ca2(+)-mobilizing, and mitogenic effects of endothelin and vasoactive intestinal contractor in mouse 3T3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Fabregat, I.; Rozengurt, E. (Imperial Cancer Research Fund, London (England))

    1990-10-01

    Endothelin (ET1) and vasoactive intestinal contractor (VIC) stimulate quiescent Swiss 3T3 cells to resume DNA synthesis acting synergistically with epidermal growth factors (EGF) and other mitogens. The peptide (D-Arg1,D-Phe5,D-Trp7,9,Leu11) substance P has been identified as a broad spectrum neuropeptide antagonist which blocks the binding and biological effects of the Ca2(+)-mobilizing neuropeptides bombesin, vasopressin, and bradykinin. In the present study we show that (D-Arg1,D-Phe5,D-Trp7,9,Leu11) substance P also acts as an ET1/VIC antagonist as judged by the following criteria: (a) inhibition of specific 125I-labelled ET1 binding to a ET1/VIC receptor in a competitive and dose-dependent manner; (b) blocking of the rapid increase in the cytosolic Ca2+ concentration promoted by ET1 or VIC; and (c) inhibition of DNA synthesis stimulated by VIC in the presence of EGF. The inhibitory effects of (D-Arg1,D-Phe5,D-Trp7,9,Leu 11) substance P on Ca2+ mobilization and DNA synthesis were reversed by increasing the concentration of VIC. This is the first time that a peptide structurally unrelated to ET1 or VIC is shown to block the binding and mitogenic effects of peptides of the endothelin family.

  2. Autocrine effects of neuromedin B stimulate the proliferation of rat primary osteoblasts.

    Science.gov (United States)

    Saito, Hiroki; Nakamachi, Tomoya; Inoue, Kazuhiko; Ikeda, Ryuji; Kitamura, Kazuo; Minamino, Naoto; Shioda, Seiji; Miyata, Atsuro

    2013-05-01

    Neuromedin B (NMB) is a mammalian bombesin-like peptide that regulates exocrine/endocrine secretion, smooth muscle contraction, body temperature, and the proliferation of some cell types. Here, we show that mRNA encoding Nmb and its receptor (Nmbr) are expressed in rat bone tissue. Immunohistochemical analysis demonstrated that NMB and NMBR colocalize in osteoblasts, epiphyseal chondrocytes, and proliferative chondrocytes of growth plates from mouse hind limbs. Then, we investigated the effect of NMB on the proliferation of rat primary cultured osteoblasts. Proliferation assays and 5-bromo-2'-deoxyuridine incorporation assays demonstrated that NMB augments the cell number and enhances DNA synthesis in osteoblasts. Pretreatment with the NMBR antagonist BIM23127 inhibited NMB-induced cell proliferation and DNA synthesis. Western blot analysis showed that NMB activates ERK1/2 MAPK signaling in osteoblasts. Pretreatment with the MAPK/ERK kinase inhibitor U0126 attenuated NMB-induced cell proliferation and DNA synthesis. We also investigated the effects of molecules that contribute to osteoblast proliferation and differentiation on Nmb expression in osteoblasts. Real-time PCR analysis demonstrated that 17β-estradiol (E2) and transforming growth factor β1 increase and decrease Nmb mRNA expression levels respectively. Finally, proliferation assays revealed that the NMBR antagonist BIM23127 suppresses E2-induced osteoblast proliferation. These results suggest that NMB/NMBR signaling plays an autocrine or paracrine role in osteoblast proliferation and contributes to the regulation of bone formation. PMID:23428580

  3. Hypoxia regulates the expression of the neuromedin B receptor through a mechanism dependent on hypoxia-inducible factor-1α.

    Directory of Open Access Journals (Sweden)

    Hyun-Joo Park

    Full Text Available The neuromedin B receptor (NMB-R, a member of the mammalian bombesin receptor family, is frequently overexpressed in various tumors. In the present study, we found that exposure to hypoxic conditions increases the levels of NMBR mRNA and protein in breast cancer cells, which are tightly regulated by hypoxia-inducible factor-1α (HIF-1α. We confirmed the effect of HIF-1α on NMBR transcription by performing an NMBR promoter-driven reporter assay and then identified a functional hypoxia-responsive element (HRE in the human NMBR promoter region. Further, the binding of HIF-1α to the NMBR promoter was corroborated by electrophoretic mobility shift and chromatin immunoprecipitation assays, which showed that HIF-1α specifically and directly bound to the NMBR promoter in response to hypoxia. Immunohistochemical analysis of a xenograft and a human breast cancer tissue array revealed a significant correlation between NMB-R and HIF-1α expression. Taken together, our findings indicate that hypoxia induces NMB-R expression through a novel mechanism to regulate HIF-1α expression in breast cancer cells.

  4. The peptidergic control circuit for sighing.

    Science.gov (United States)

    Li, Peng; Janczewski, Wiktor A; Yackle, Kevin; Kam, Kaiwen; Pagliardini, Silvia; Krasnow, Mark A; Feldman, Jack L

    2016-02-18

    Sighs are long, deep breaths expressing sadness, relief or exhaustion. Sighs also occur spontaneously every few minutes to reinflate alveoli, and sighing increases under hypoxia, stress, and certain psychiatric conditions. Here we use molecular, genetic, and pharmacologic approaches to identify a peptidergic sigh control circuit in murine brain. Small neural subpopulations in a key breathing control centre, the retrotrapezoid nucleus/parafacial respiratory group (RTN/pFRG), express bombesin-like neuropeptide genes neuromedin B (Nmb) or gastrin-releasing peptide (Grp). These project to the preBötzinger Complex (preBötC), the respiratory rhythm generator, which expresses NMB and GRP receptors in overlapping subsets of ~200 neurons. Introducing either neuropeptide into preBötC or onto preBötC slices, induced sighing or in vitro sigh activity, whereas elimination or inhibition of either receptor reduced basal sighing, and inhibition of both abolished it. Ablating receptor-expressing neurons eliminated basal and hypoxia-induced sighing, but left breathing otherwise intact initially. We propose that these overlapping peptidergic pathways comprise the core of a sigh control circuit that integrates physiological and perhaps emotional input to transform normal breaths into sighs. PMID:26855425

  5. Cloning of neuromedin B and its receptor in the rabbit and generating a polyclonal antibody to the neuromedin B protein.

    Science.gov (United States)

    Guo, Ting-Ting; Su, Juan; Ma, Zhi-Yu; Ma, Jun-Xiao; Jin, Meng-Meng; Li, Xiang; Lei, Zhi-Hai

    2015-06-10

    Neuromedin B (NMB) is a highly conserved bombesin-related neuropeptide found in mammals. Neuromedin B (NMB) executes its effect by binding to the cell surface receptor, neuromedin B receptor (NMBR). In this study, we cloned the rabbit NMB and NMBR genes. The similarity and phylogenetic analyses of NMB and NMBR gene sequences were performed. The expression of NMB and NMBR mRNA in the rabbit was investigated using real-time RT-PCR. Our bioinformatic analysis demonstrated that the cloned rabbit NMB precursor cDNA encoded Gly-His-Phe-Met-NH2 amino acids at the C-terminus, and that its receptor possessed typical transmembrane features. The NMB mRNA was highly expressed in the CNS, while the NMBR mRNA was widely expressed in many tissues, with the highest expression in the gastrointestinal tract. The studies on the NMB distribution and function are limited by the lack of a specific antibody to this neuropeptide. In this paper, polyclonal NMB antibody was generated in mice. Western blotting analysis revealed that the prepared antibody could specifically recognize the recombinant and the endogenous NMB proteins. Immunohistochemistry analysis indicated that the NMB protein was localized in the cytoplasm of the pituitary cells. The existence of NMB protein in the hypothalamic-pituitary-gonadal axis suggests that NMB might function in rabbit reproduction. PMID:25796599

  6. Interrogating the Role of Receptor-Mediated Mechanisms: Biological Fate of Peptide-Functionalized Radiolabeled Gold Nanoparticles in Tumor Mice.

    Science.gov (United States)

    Silva, Francisco; Zambre, Ajit; Campello, Maria Paula Cabral; Gano, Lurdes; Santos, Isabel; Ferraria, Ana Maria; Ferreira, Maria João; Singh, Amolak; Upendran, Anandhi; Paulo, António; Kannan, Raghuraman

    2016-04-20

    To get a better insight on the transport mechanism of peptide-conjugated nanoparticles to tumors, we performed in vivo biological studies of bombesin (BBN) peptide functionalized gold nanoparticles (AuNPs) in human prostate tumor bearing mice. Initially, we sought to compare AuNPs with thiol derivatives of acyclic and macrocyclic chelators of DTPA and DOTA types. The DTPA derivatives were unable to provide a stable coordination of (67)Ga, and therefore, the functionalization with the BBN analogues was pursued for the DOTA-containing AuNPs. The DOTA-coated AuNPs were functionalized with BBN[7-14] using a unidentate cysteine group or a bidentate thioctic group to attach the peptide. AuNPs functionalized with thioctic-BBN displayed the highest in vitro cellular internalization (≈ 25%, 15 min) in gastrin releasing peptide (GRP) receptor expressing cancer cells. However, these results fail to translate to in vivo tumor uptake. Biodistribution studies following intravenous (IV) and intraperitoneal (IP) administration of nanoconjugates in tumor bearing mice indicated that the presence of BBN influences to some degree the biological profile of the nanoconstructs. For IV administration, the receptor-mediated pathway appears to be outweighed by the EPR effect. By contrast, in IP administration, it is reasoned that the GRPr-mediated mechanism plays a role in pancreas uptake. PMID:27003101

  7. 68Ga-AMBA and 18 F-FDG for preclinical PET imaging of breast cancer: effect of tamoxifen treatment on tracer uptake by tumor

    International Nuclear Information System (INIS)

    Introduction: AMBA is a bombesin analogue that binds to GRPr. In a mouse model of estrogen-dependent human breast cancer, we tested whether 68Ga-AMBA can be used for PET detection of GRPr-expressing tumors and could be more accurate than 18F-FDG to monitor tumor response to hormone therapy. Methods: The radiolabeling of 68Ga-AMBA was automated using a R and D Synchrom module. ZR75-1, a breast cancer cell line, was xenografted in nude mice. 68Ga-AMBA tumor uptake was compared with that of 18F-FDG before and after treatment with tamoxifen. Results: AMBA was 68Ga-radiolabelled in 30 min with 95.3% yield and purity ≥ 98%. Prior to treatment, 68Ga-AMBA was highly concentrated into tumors (tumor to non-tumor ratio = 2.4 vs. 1.3 with 18F-FDG). With tamoxifen treatment (n = 6) 68Ga-AMBA uptake plateaued after 1 week and decreased after 2 weeks, with a significant reduction compared to controls (n = 4). In contrast the effect of tamoxifen treatment could not be appreciated using 18F-FDG. Conclusions: 68Ga-AMBA appeared better than 18F-FDG to visualize and monitor the response to hormone treatment in this breast cancer model

  8. A solvent resistant lab-on-chip platform for radiochemistry applications.

    Science.gov (United States)

    Rensch, Christian; Lindner, Simon; Salvamoser, Ruben; Leidner, Stephanie; Böld, Christoph; Samper, Victor; Taylor, David; Baller, Marko; Riese, Stefan; Bartenstein, Peter; Wängler, Carmen; Wängler, Björn

    2014-07-21

    The application of microfluidics to the synthesis of Positron Emission Tomography (PET) tracers has been explored for more than a decade. Microfluidic benefits such as superior temperature control have been successfully applied to PET tracer synthesis. However, the design of a compact microfluidic platform capable of executing a complete PET tracer synthesis workflow while maintaining prospects for commercialization remains a significant challenge. This study uses an integral system design approach to tackle commercialization challenges such as the material to process compatibility with a path towards cost effective lab-on-chip mass manufacturing from the start. It integrates all functional elements required for a simple PET tracer synthesis into one compact radiochemistry platform. For the lab-on-chip this includes the integration of on-chip valves, on-chip solid phase extraction (SPE), on-chip reactors and a reversible fluid interface while maintaining compatibility with all process chemicals, temperatures and chip mass manufacturing techniques. For the radiochemistry device it includes an automated chip-machine interface enabling one-move connection of all valve actuators and fluid connectors. A vial-based reagent supply as well as methods to transfer reagents efficiently from the vials to the chip has been integrated. After validation of all those functional elements, the microfluidic platform was exemplarily employed for the automated synthesis of a Gastrin-releasing peptide receptor (GRP-R) binding the PEGylated Bombesin BN(7-14)-derivative ([(18)F]PESIN) based PET tracer.

  9. Conformational Dynamics of the Focal Adhesion Targeting Domain Control Specific Functions of Focal Adhesion Kinase in Cells

    KAUST Repository

    Kadaré, Gress

    2015-01-02

    Focal adhesion (FA) kinase (FAK) regulates cell survival and motility by transducing signals from membrane receptors. The C-terminal FA targeting (FAT) domain of FAK fulfils multiple functions, including recruitment to FAs through paxillin binding. Phosphorylation of FAT on Tyr925 facilitates FA disassembly and connects to the MAPK pathway through Grb2 association, but requires dissociation of the first helix (H1) of the four-helix bundle of FAT. We investigated the importance of H1 opening in cells by comparing the properties of FAK molecules containing wild-type or mutated FAT with impaired or facilitated H1 openings. These mutations did not alter the activation of FAK, but selectively affected its cellular functions, including self-association, Tyr925 phosphorylation, paxillin binding, and FA targeting and turnover. Phosphorylation of Tyr861, located between the kinase and FAT domains, was also enhanced by the mutation that opened the FAT bundle. Similarly phosphorylation of Ser910 by ERK in response to bombesin was increased by FAT opening. Although FAK molecules with the mutation favoring FAT opening were poorly recruited at FAs, they efficiently restored FA turnover and cell shape in FAK-deficient cells. In contrast, the mutation preventing H1 opening markedly impaired FAK function. Our data support the biological importance of conformational dynamics of the FAT domain and its functional interactions with other parts of the molecule.

  10. Insights into the Binding Sites of Organometallic Ruthenium Anticancer Compounds on Peptides Using Ultra-High Resolution Mass Spectrometry

    Science.gov (United States)

    Wills, Rebecca H.; Habtemariam, Abraha; Lopez-Clavijo, Andrea F.; Barrow, Mark P.; Sadler, Peter J.; O'Connor, Peter B.

    2014-04-01

    The binding sites of two ruthenium(II) organometallic complexes of the form [(η6-arene)Ru( N, N)Cl]+, where arene/ N, N = biphenyl (bip)/bipyridine (bipy) for complex AH076, and biphenyl (bip)/ o-phenylenediamine ( o-pda) for complex AH078, on the peptides angiotensin and bombesin have been investigated using Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. Fragmentation was performed using collisionally activated dissociation (CAD), with, in some cases, additional data being provided by electron capture dissociation (ECD). The primary binding sites were identified as methionine and histidine, with further coordination to phenylalanine, potentially through a π-stacking interaction, which has been observed here for the first time. This initial peptide study was expanded to investigate protein binding through reaction with insulin, on which the binding sites proposed are histidine, glutamic acid, and tyrosine. Further reaction of the ruthenium complexes with the oxidized B chain of insulin, in which two cysteine residues are oxidized to cysteine sulfonic acid (Cys-SO3H), and glutathione, which had been oxidized with hydrogen peroxide to convert the cysteine to cysteine sulfonic acid, provided further support for histidine and glutamic acid binding, respectively.

  11. Structural and functional localization of airway effects from episodic exposure of infant monkeys to allergen and/or ozone

    International Nuclear Information System (INIS)

    Both allergen and ozone exposure increase asthma symptoms and airway responsiveness in children. Little is known about how these inhalants may differentially modify airway responsiveness in large proximal as compared to small distal airways. We evaluated whether bronchi and respiratory bronchioles from infant monkeys exposed episodically to allergen and/or ozone differentially develop intrinsic hyperresponsiveness to methacholine and whether eosinophils and/or pulmonary neuroendocrine cells play a role. Infant monkeys were exposed episodically for 5 months to: (1) filtered air, (2) aerosolized house dust mite allergen, (3) ozone 0.5 ppm, or (4) house dust mite allergen + ozone. Studying the function/structure relationship of the same lung slices, we evaluated methacholine airway responsiveness and histology of bronchi and respiratory bronchioles. In bronchi, intrinsic responsiveness was increased by allergen exposure, an effect reduced by bombesin antagonist. In respiratory bronchioles, intrinsic airway responsiveness was increased by allergen + ozone exposure. Eosinophils were increased by allergen and allergen + ozone exposure in bronchi and by allergen exposure in respiratory bronchioles. In both airways, exposure to allergen + ozone resulted in fewer tissue eosinophils than did allergen exposure alone. In bronchi, but not in respiratory bronchioles, the number of eosinophils and neuroendocrine cells correlated with airway responsiveness. We conclude that episodically exposing infant monkeys to house dust mite allergen with or without ozone increased intrinsic airway responsiveness to methacholine in bronchi differently than in respiratory bronchioles. In bronchi, eosinophils and neuroendocrine cells may play a role in the development of airway hyperresponsiveness

  12. Afferent signals regulating food intake.

    Science.gov (United States)

    Bray, G A

    2000-08-01

    Food intake is a regulated system. Afferent signals provide information to the central nervous system, which is the centre for the control of satiety or food seeking. Such signals can begin even before food is ingested through visual, auditory and olfactory stimuli. One of the recent interesting findings is the demonstration that there are selective fatty acid taste receptors on the tongue of rodents. The suppression of food intake by essential fatty acids infused into the stomach and the suppression of electrical signals in taste buds reflect activation of a K rectifier channel (K 1.5). In animals that become fat eating a high-fat diet the suppression of this current by linoleic acid is less than that in animals that are resistant to obesity induced by dietary fat. Inhibition of fatty acid oxidation with either mercaptoacetate (which blocks acetyl-CoA dehydrogenase) or methylpalmoxirate will increase food intake. When animals have a choice of food, mercaptoacetate stimulates the intake of protein and carbohydrate, but not fat. Afferent gut signals also signal satiety. The first of these gut signals to be identified was cholecystokinin (CCK). When CCK acts on CCK-A receptors in the gastrointestinal tract, food intake is suppressed. These signals are transmitted by the vagus nerve to the nucleus tractus solitarius and thence to higher centres including the lateral parabrachial nucleus, amygdala, and other sites. Rats that lack the CCK-A receptor become obese, but transgenic mice lacking CCK-A receptors do not become obese. CCK inhibits food intake in human subjects. Enterostatin, the pentapeptide produced when pancreatic colipase is cleaved in the gut, has been shown to reduce food intake. This peptide differs in its action from CCK by selectively reducing fat intake. Enterostatin reduces hunger ratings in human subjects. Bombesin and its human analogue, gastrin inhibitory peptide (also gastrin-insulin peptide), reduce food intake in obese and lean subjects. Animals

  13. Expression of early growth response factor-1 in rats with cerulein-induced acute pancreatitis and its significance

    Institute of Scientific and Technical Information of China (English)

    Lan-Bo Gong; Li He; Yang Liu; Xue-Qing Chen; Bo Jiang

    2005-01-01

    AIM: To observe the expressions of early growth response factor-1 (Egr-L) and tissue factor (TF) in rats with cerulein-induced acute pancreatitis and to explore its significance.METHODS: A large dose of cerulein was used to create the experimental acute pancreatitis model in rats. The changes of Egr-1 mRNA and protein in rats were observed during 30 min to 4 h after the treatment and immunohistochemical method was used to observe the localized expression of Egr-1 in tissues. In addition to the mRNA expression of Egr-1 target gene, TF was also observed. A blank control group, and a bombesinadministered group were used for comparison.RESULTS: After the stimulation of a large dose of cerulein,the rats showed typical inflammatory changes of acute pancreatitis. Thirty minutes after the stimulation, the mRNA expression of Egr-1 in the pancreatic tissue reached its peak and then declined, while the expression of Egr-1protein reached its peak 2 h after the stimulation.Histologically, 2 h after the stimulation, almost all pancreatic acinar cells had the expression of Egr-1 protein,which was focused in the nuclei. The mRNA expression of TF occurred 1 h after the stimulation and gradually increased within 4 h. However, a large dose of bombesin only stimulated the pancreatic tissue to produce a little mRNA expression of Egr-1 and no mRNA expression of Egr-1 protein and TF.CONCLUSION: Egr-1 as a pro-inflammatory transcription factor may play an important role in the pathogenesis of acute pancreatitis by modulating the expression of TF.

  14. Feeding and the rhodopsin family G-Protein Coupled Receptors (GPCRs in nematodes and arthropods

    Directory of Open Access Journals (Sweden)

    Joao Carlos dos Reis Cardoso

    2012-12-01

    Full Text Available In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologues of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster, suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologues of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors.

  15. Feeding and the rhodopsin family g-protein coupled receptors in nematodes and arthropods.

    Science.gov (United States)

    Cardoso, João C R; Félix, Rute C; Fonseca, Vera G; Power, Deborah M

    2012-01-01

    In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors. PMID:23264768

  16. Preclinical Study on GRPR-Targeted (68)Ga-Probes for PET Imaging of Prostate Cancer.

    Science.gov (United States)

    Sun, Yao; Ma, Xiaowei; Zhang, Zhe; Sun, Ziyan; Loft, Mathias; Ding, Bingbing; Liu, Changhao; Xu, Liying; Yang, Meng; Jiang, Yuxin; Liu, Jianfeng; Xiao, Yuling; Cheng, Zhen; Hong, Xuechuan

    2016-08-17

    Gastrin-releasing peptide receptor (GRPR) targeted positron emission tomography (PET) is a highly promising approach for imaging of prostate cancer (PCa) in small animal models and patients. Developing a GRPR-targeted PET probe with excellent in vivo performance such as high tumor uptake, high contrast, and optimal pharmacokinetics is still very challenging. Herein, a novel bombesin (BBN) analogue (named SCH1) based on JMV594 peptide modified with an 8-amino octanoic acid spacer (AOC) was thus designed and conjugated with the metal chelator 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA). The resulting NODAGA-SCH1 was then radiolabeled with (68)Ga and evaluated for PET imaging of PCa. Compared with (68)Ga-NODAGA-JMV594 probe, (68)Ga-NODAGA-SCH1 exhibited excellent PET/CT imaging properties on PC-3 tumor-bearing nude mice, such as high tumor uptake (5.80 ± 0.42 vs 3.78 ± 0.28%ID/g, 2 h) and high tumor/muscle contrast (16.6 ± 1.50 vs 8.42 ± 0.61%ID/g, 2 h). Importantly, biodistribution data indicated a relatively similar accumulation of (68)Ga-NODAGA-SCH1 was observed in the liver (4.21 ± 0.42%ID/g) and kidney (3.41 ± 0.46%ID/g) suggesting that the clearance is through both the kidney and the liver. Overall, (68)Ga-NODAGA-SCH1 showed promising in vivo properties and is a promising candidate for translation into clinical PET-imaging of PCa patients. PMID:27399868

  17. Neuromedin B and Its Receptor: Gene Cloning, Tissue Distribution and Expression Levels of the Reproductive Axis in Pigs

    Science.gov (United States)

    Ma, Zhiyu; Su, Juan; Guo, Tingting; Jin, Mengmeng; Li, Xiang; Lei, Zhihai; Hou, Yuanlong; Li, Xiaoliang; Jia, Cuicui; Zhang, Zheng; Ahmed, Ejlal

    2016-01-01

    Neuromedin B is one member of a family of bombesin-like peptides, which performs a variety of physiological functions via their receptor (NMBR) in most mammals. However, the genes encoding NMB and NMBR and their functions especially reproduction of the pigs are currently not fully understood. To research the physiological functions of NMB, we cloned and analyzed the NMB and NMBR genes, and systematically investigated the expression levels of NMB and NMBR mRNA using relative real-time PCR and the distribution of NMBR by immunohistochemistry (IHC). Experimental results show that the sequences of the amino acid and gene of NMB and NMBR were highly conservative and homology in many species, Significantly, the relative RT-PCR results revealed that NMB was mainly expressed in the central nervous system (CNS), whereas NMBR is highly expressed in peripheral tissues and organs, such as endocrine tissues, glands and reproductive organs. The IHC results show that NMBR positive cells were widely distributed in the body, such as respiratory and circulatory system, digestive system, urogenital system, in lymphatic organs and in the endocrine system. We also systematically investigated expression levels of NMB and NMBR in the reproductive axis using relative real-time PCR. In sow estrous cycle, the hypothalamic levels of both NMB and NMBR mRAN were similar, but the expression levels of the pituitary were negatively correlated. Expression levels in the ovarian system are lowest in metestrus phases and highest in proestrus and estrus phases. In boar post-natal development stages, the hypothalamic, pituitary and testicular levels of NMB and NMBR mRNAs showed developmental changes on postnatal day 30, 60, 90 and 120. Taken together, this study provided molecular and morphological data necessary for further research of physiological function of NMB/NMBR system in the pigs. PMID:27010315

  18. Co-expressed peptide receptors in breast cancer as a molecular basis for in vivo multireceptor tumour targeting

    International Nuclear Information System (INIS)

    Breast cancers can express different types of peptide receptors such as somatostatin, vasoactive intestinal peptide (VIP), gastrin-releasing peptide (GRP) and NPY(Y1) receptors. The aim of this in vitro study was to evaluate which is the most appropriate peptide receptor or peptide receptor combination for in vivo diagnostic and therapeutic targeting of breast cancers. Seventy-seven primary breast cancers and 15 breast cancer lymph node metastases were investigated in vitro for their expression of somatostatin, VPAC1, GRP and NPY(Y1) receptors using in vitro receptor autoradiography on successive tissue sections with 125I-[Tyr3]-octreotide, 125I-VIP, 125I-[Tyr4]-bombesin and 125I-[Leu31,Pro34]-PYY respectively. This study identified two groups of tumours: a group of 68 tumours (88%) with at least one receptor expressed at high density (>2,000 dpm/mg tissue) that may provide a strong predictive value for successful in vivo targeting, and a group of nine tumours (12%) with no receptors or only a low density of them (1) receptors, 25 (37%) expressed VPAC1 receptors and 14 (21%) expressed somatostatin receptors. Mean density was 9,819±530 dpm/mg tissue for GRP receptors, 9,135±579 dpm/mg for NPY(Y1) receptors, 4,337±528 dpm/mg for somatostatin receptors and 3,437±306 dpm/mg for VPAC1 receptors. It is of note that tumours expressing NPY(Y1) or GRP receptors, or both, were found in 63/68 (93%) cases. Lymph node metastases showed a similar receptor profile to the corresponding primary tumour. This in vitro study strongly suggests that the combination of radiolabelled GRP and Y1 analogues should allow targeting of breast carcinomas and their lymph node metastases for in vivo peptide receptor scintigraphy and radiotherapy. (orig.)

  19. Neuromedin B and Its Receptor: Gene Cloning, Tissue Distribution and Expression Levels of the Reproductive Axis in Pigs.

    Directory of Open Access Journals (Sweden)

    Zhiyu Ma

    Full Text Available Neuromedin B is one member of a family of bombesin-like peptides, which performs a variety of physiological functions via their receptor (NMBR in most mammals. However, the genes encoding NMB and NMBR and their functions especially reproduction of the pigs are currently not fully understood. To research the physiological functions of NMB, we cloned and analyzed the NMB and NMBR genes, and systematically investigated the expression levels of NMB and NMBR mRNA using relative real-time PCR and the distribution of NMBR by immunohistochemistry (IHC. Experimental results show that the sequences of the amino acid and gene of NMB and NMBR were highly conservative and homology in many species, Significantly, the relative RT-PCR results revealed that NMB was mainly expressed in the central nervous system (CNS, whereas NMBR is highly expressed in peripheral tissues and organs, such as endocrine tissues, glands and reproductive organs. The IHC results show that NMBR positive cells were widely distributed in the body, such as respiratory and circulatory system, digestive system, urogenital system, in lymphatic organs and in the endocrine system. We also systematically investigated expression levels of NMB and NMBR in the reproductive axis using relative real-time PCR. In sow estrous cycle, the hypothalamic levels of both NMB and NMBR mRAN were similar, but the expression levels of the pituitary were negatively correlated. Expression levels in the ovarian system are lowest in metestrus phases and highest in proestrus and estrus phases. In boar post-natal development stages, the hypothalamic, pituitary and testicular levels of NMB and NMBR mRNAs showed developmental changes on postnatal day 30, 60, 90 and 120. Taken together, this study provided molecular and morphological data necessary for further research of physiological function of NMB/NMBR system in the pigs.

  20. Neuromedin B and Its Receptor: Gene Cloning, Tissue Distribution and Expression Levels of the Reproductive Axis in Pigs.

    Science.gov (United States)

    Ma, Zhiyu; Su, Juan; Guo, Tingting; Jin, Mengmeng; Li, Xiang; Lei, Zhihai; Hou, Yuanlong; Li, Xiaoliang; Jia, Cuicui; Zhang, Zheng; Ahmed, Ejlal

    2016-01-01

    Neuromedin B is one member of a family of bombesin-like peptides, which performs a variety of physiological functions via their receptor (NMBR) in most mammals. However, the genes encoding NMB and NMBR and their functions especially reproduction of the pigs are currently not fully understood. To research the physiological functions of NMB, we cloned and analyzed the NMB and NMBR genes, and systematically investigated the expression levels of NMB and NMBR mRNA using relative real-time PCR and the distribution of NMBR by immunohistochemistry (IHC). Experimental results show that the sequences of the amino acid and gene of NMB and NMBR were highly conservative and homology in many species, Significantly, the relative RT-PCR results revealed that NMB was mainly expressed in the central nervous system (CNS), whereas NMBR is highly expressed in peripheral tissues and organs, such as endocrine tissues, glands and reproductive organs. The IHC results show that NMBR positive cells were widely distributed in the body, such as respiratory and circulatory system, digestive system, urogenital system, in lymphatic organs and in the endocrine system. We also systematically investigated expression levels of NMB and NMBR in the reproductive axis using relative real-time PCR. In sow estrous cycle, the hypothalamic levels of both NMB and NMBR mRAN were similar, but the expression levels of the pituitary were negatively correlated. Expression levels in the ovarian system are lowest in metestrus phases and highest in proestrus and estrus phases. In boar post-natal development stages, the hypothalamic, pituitary and testicular levels of NMB and NMBR mRNAs showed developmental changes on postnatal day 30, 60, 90 and 120. Taken together, this study provided molecular and morphological data necessary for further research of physiological function of NMB/NMBR system in the pigs. PMID:27010315

  1. VALIDATION OF NEUROTENSIN TETRA-BRANCHED PEPTIDES AS TUMOR TARGETING AGENTS IN PANCREAS, COLON AND BLADDER CARCINOMA

    Directory of Open Access Journals (Sweden)

    N. Ravenni

    2012-05-01

    Full Text Available The identification of new tumor targeting agents, which might allow either cancer cell tracing or ther- apy, is a crucial issue in cancer research. Membrane receptors for endogenous peptides such as neu- rotensin, somatostatin, bombesin and many others are over-expressed in different human cancers and could therefore be targeted as tumor-specific antigens. In the meantime the extremely short half-life of pep- tides impeded their development for effective pep- tide-based tumor targeting strategies. We synthesized tetra-branched neurotensin peptides (NT4, which ensure extremely long half-life main- taining peptide specificity and increasing avidity through multimeric binding. Moreover this bio-syn- thetical strategy allows a considerable modularity of peptides through the conjugation of different func- tional unit, such as fluorophore, radioactive moieties or chemotherapeutic drugs. Aim of our studies is to validate NT4 for cancer cell tracing in different human tumors. In this view we use fluorophore-conjugated NT4 to discriminate be- tween tumor and healthy tissue obtained by surgical samples from pancreas, colon and bladder carcinoma. Peptide binding on tumor and healthy biopsies was measured in each patient by quantitative analysis of confocal microscopy images. These results show a considerable difference in fluorescence emission be- tween healthy and tumor samples in colon, pancreas and bladder cancer, opening the way to the develop- ment of NT4 as selective diagnostic tools for these pathologies. Moreover our peptides can be conju- gated with different chemotherapeutic moieties in order to allow the selective killing of tumor cells.

  2. Gastrin-releasing peptide signaling plays a limited and subtle role in amygdala physiology and aversive memory.

    Directory of Open Access Journals (Sweden)

    Frederique Chaperon

    Full Text Available Links between synaptic plasticity in the lateral amygdala (LA and Pavlovian fear learning are well established. Neuropeptides including gastrin-releasing peptide (GRP can modulate LA function. GRP increases inhibition in the LA and mice lacking the GRP receptor (GRPR KO show more pronounced and persistent fear after single-trial associative learning. Here, we confirmed these initial findings and examined whether they extrapolate to more aspects of amygdala physiology and to other forms of aversive associative learning. GRP application in brain slices from wildtype but not GRPR KO mice increased spontaneous inhibitory activity in LA pyramidal neurons. In amygdala slices from GRPR KO mice, GRP did not increase inhibitory activity. In comparison to wildtype, short- but not long-term plasticity was increased in the cortico-lateral amygdala (LA pathway of GRPR KO amygdala slices, whereas no changes were detected in the thalamo-LA pathway. In addition, GRPR KO mice showed enhanced fear evoked by single-trial conditioning and reduced spontaneous firing of neurons in the central nucleus of the amygdala (CeA. Altogether, these results are consistent with a potentially important modulatory role of GRP/GRPR signaling in the amygdala. However, administration of GRP or the GRPR antagonist (D-Phe(6, Leu-NHEt(13, des-Met(14-Bombesin (6-14 did not affect amygdala LTP in brain slices, nor did they affect the expression of conditioned fear following intra-amygdala administration. GRPR KO mice also failed to show differences in fear expression and extinction after multiple-trial fear conditioning, and there were no differences in conditioned taste aversion or gustatory neophobia. Collectively, our data indicate that GRP/GRPR signaling modulates amygdala physiology in a paradigm-specific fashion that likely is insufficient to generate therapeutic effects across amygdala-dependent disorders.

  3. Gastrin-releasing peptide signaling plays a limited and subtle role in amygdala physiology and aversive memory.

    Science.gov (United States)

    Chaperon, Frederique; Fendt, Markus; Kelly, Peter H; Lingenhoehl, Kurt; Mosbacher, Johannes; Olpe, Hans-Rudolf; Schmid, Peter; Sturchler, Christine; McAllister, Kevin H; van der Putten, P Herman; Gee, Christine E

    2012-01-01

    Links between synaptic plasticity in the lateral amygdala (LA) and Pavlovian fear learning are well established. Neuropeptides including gastrin-releasing peptide (GRP) can modulate LA function. GRP increases inhibition in the LA and mice lacking the GRP receptor (GRPR KO) show more pronounced and persistent fear after single-trial associative learning. Here, we confirmed these initial findings and examined whether they extrapolate to more aspects of amygdala physiology and to other forms of aversive associative learning. GRP application in brain slices from wildtype but not GRPR KO mice increased spontaneous inhibitory activity in LA pyramidal neurons. In amygdala slices from GRPR KO mice, GRP did not increase inhibitory activity. In comparison to wildtype, short- but not long-term plasticity was increased in the cortico-lateral amygdala (LA) pathway of GRPR KO amygdala slices, whereas no changes were detected in the thalamo-LA pathway. In addition, GRPR KO mice showed enhanced fear evoked by single-trial conditioning and reduced spontaneous firing of neurons in the central nucleus of the amygdala (CeA). Altogether, these results are consistent with a potentially important modulatory role of GRP/GRPR signaling in the amygdala. However, administration of GRP or the GRPR antagonist (D-Phe(6), Leu-NHEt(13), des-Met(14))-Bombesin (6-14) did not affect amygdala LTP in brain slices, nor did they affect the expression of conditioned fear following intra-amygdala administration. GRPR KO mice also failed to show differences in fear expression and extinction after multiple-trial fear conditioning, and there were no differences in conditioned taste aversion or gustatory neophobia. Collectively, our data indicate that GRP/GRPR signaling modulates amygdala physiology in a paradigm-specific fashion that likely is insufficient to generate therapeutic effects across amygdala-dependent disorders.

  4. Cross-inhibition of NMBR and GRPR signaling maintains normal histaminergic itch transmission.

    Science.gov (United States)

    Zhao, Zhong-Qiu; Wan, Li; Liu, Xian-Yu; Huo, Fu-Quan; Li, Hui; Barry, Devin M; Krieger, Stephanie; Kim, Seungil; Liu, Zhong-Chun; Xu, Jinbin; Rogers, Buck E; Li, Yun-Qing; Chen, Zhou-Feng

    2014-09-10

    We previously showed that gastrin-releasing peptide receptor (GRPR) in the spinal cord is important for mediating nonhistaminergic itch. Neuromedin B receptor (NMBR), the second member of the mammalian bombesin receptor family, is expressed in a largely nonoverlapping pattern with GRPR in the superficial spinal cord, and its role in itch transmission remains unclear. Here, we report that Nmbr knock-out (KO) mice exhibited normal scratching behavior in response to intradermal injection of pruritogens. However, mice lacking both Nmbr and Grpr (DKO mice) showed significant deficits in histaminergic itch. In contrast, the chloroquine (CQ)-evoked scratching behavior of DKO mice is not further reduced compared with Grpr KO mice. These results suggest that NMBR and GRPR could compensate for the loss of each other to maintain normal histamine-evoked itch, whereas GRPR is exclusively required for CQ-evoked scratching behavior. Interestingly, GRPR activity is enhanced in Nmbr KO mice despite the lack of upregulation of Grpr expression; so is NMBR in Grpr KO mice. We found that NMB acts exclusively through NMBR for itch transmission, whereas GRP can signal through both receptors, albeit to NMBR to a much lesser extent. Although NMBR and NMBR(+) neurons are dispensable for histaminergic itch, GRPR(+) neurons are likely to act downstream of NMBR(+) neurons to integrate NMB-NMBR-encoded histaminergic itch information in normal physiological conditions. Together, we define the respective function of NMBR and GRPR in itch transmission, and reveal an unexpected relationship not only between the two receptors but also between the two populations of interneurons in itch signaling. PMID:25209280

  5. The majority of dorsal spinal cord gastrin releasing peptide is synthesized locally whereas neuromedin B is highly expressed in pain- and itch-sensing somatosensory neurons

    Directory of Open Access Journals (Sweden)

    Fleming Michael S

    2012-07-01

    Full Text Available Abstract Background Itch is one of the major somatosensory modalities. Some recent findings have proposed that gastrin releasing peptide (Grp is expressed in a subset of dorsal root ganglion (DRG neurons and functions as a selective neurotransmitter for transferring itch information to spinal cord interneurons. However, expression data from public databases and earlier literatures indicate that Grp mRNA is only detected in dorsal spinal cord (dSC whereas its family member neuromedin B (Nmb is highly expressed in DRG neurons. These contradictory results argue that a thorough characterization of the expression of Grp and Nmb is warranted. Findings Grp mRNA is highly expressed in dSC but is barely detectable in DRGs of juvenile and adult mice. Anti-bombesin serum specifically recognizes Grp but not Nmb. Grp is present in a small number of small-diameter DRG neurons and in abundance in layers I and II of the spinal cord. The reduction of dSC Grp after dorsal root rhizotomy is significantly different from those of DRG derived markers but similar to that of a spinal cord neuronal marker. Double fluorescent in situ of Nmb and other molecular markers indicate that Nmb is highly and selectively expressed in nociceptive and itch-sensitive DRG neurons. Conclusion The majority of dSC Grp is synthesized locally in dorsal spinal cord neurons. On the other hand, Nmb is highly expressed in pain- and itch-sensing DRG neurons. Our findings provide direct anatomic evidence that Grp could function locally in the dorsal spinal cord in addition to its roles in DRG neurons and that Nmb has potential roles in nociceptive and itch-sensitive neurons. These results will improve our understanding about roles of Grp and Nmb in mediating itch sensation.

  6. Radiochemical investigations of 177Lu-DOTA-8-Aoc-BBN[7-14]NH2: an in vitro/in vivo assessment of the targeting ability of this new radiopharmaceutical for PC-3 human prostate cancer cells

    International Nuclear Information System (INIS)

    Bombesin (BBN), a 14 amino acid peptide, is an analogue of human gastrin releasing peptide (GRP) that binds to GRP receptors (GRPr) with high affinity and specificity. The GRPr is over expressed on a variety of human cancer cells including prostate, breast, lung, and pancreatic cancers. The specific aim of this study was to identify a BBN analogue that can be radiolabeled with 177Lu and maintains high specificity for GRPr positive prostate cancer tumors in vivo. A preselected synthetic sequence via solid phase peptide synthesis (SPPS) was designed to produce a DOTA-BBN (DOTA 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) conjugate with the following general structure: DOTA-X-Q-W-A-V-G-H-L-M-(NH2), where the spacer group, X = ω-NH2(CH2)7COOH (8-Aoc). The BBN-construct was purified by reversed phase-HPLC (RP-HPLC). Electrospray Mass Spectrometry (ES-MS) was used to characterize both metallated and non-metallated BBN-conjugates. The new DOTA-conjugate was metallated with 177Lu(III)Cl3 or non-radioactive Lu(III)Cl3. The 177Lu(III)- and non-radiolabeled Lu(III)-conjugates exhibit the same retention times under identical RP-HPLC conditions. The 177Lu-DOTA-8-Aoc-BBN[7-14]NH2 conjugate was found to exhibit optimal pharmacokinetic properties in CF-1 normal mice. In vitro and in vivo models demonstrated the ability of the 177Lu-DOTA-8-Aoc-BBN[7-14]NH2 conjugate to specifically target GRP receptors expressed on PC-3 human prostate cancer cells

  7. Regulation of feeding behavior and food intake by appetite-regulating peptides in wild-type and growth hormone-transgenic coho salmon.

    Science.gov (United States)

    White, Samantha L; Volkoff, Helene; Devlin, Robert H

    2016-08-01

    Survival, competition, growth and reproductive success in fishes are highly dependent on food intake, food availability and feeding behavior and are all influenced by a complex set of metabolic and neuroendocrine mechanisms. Overexpression of growth hormone (GH) in transgenic fish can result in greatly enhanced growth rates, feed conversion, feeding motivation and food intake. The objectives of this study were to compare seasonal feeding behavior of non-transgenic wild-type (NT) and GH-transgenic (T) coho salmon (Oncorhynchus kisutch), and to examine the effects of intraperitoneal injections of the appetite-regulating peptides cholecystokinin (CCK-8), bombesin (BBS), glucagon-like peptide-1 (GLP-1), and alpha-melanocyte-stimulating hormone (α-MSH) on feeding behavior. T salmon fed consistently across all seasons, whereas NT dramatically reduced their food intake in winter, indicating the seasonal regulation of appetite can be altered by overexpression of GH in T fish. Intraperitoneal injections of CCK-8 and BBS caused a significant and rapid decrease in food intake for both genotypes. Treatment with either GLP-1 or α-MSH resulted in a significant suppression of food intake for NT but had no effect in T coho salmon. The differential response of T and NT fish to α-MSH is consistent with the melanocortin-4 receptor system being a significant pathway by which GH acts to stimulate appetite. Taken together, these results suggest that chronically increased levels of GH alter feeding regulatory pathways to different extents for individual peptides, and that altered feeding behavior in transgenic coho salmon may arise, in part, from changes in sensitivity to peripheral appetite-regulating signals. PMID:27149948

  8. Evaluation of the internalization kinetics of the radiopharmaceutical 99mTc-N2S2-Tat(49-57)Lys3-Bn with diagnostic purposes, using comet assay

    International Nuclear Information System (INIS)

    Gastrin-rea leasing peptide receptors (GRP-r) are over expressed in breast and prostate cancer cells. Bombesin (Bn) binds specifically and strongly to GRP-r and this is the base for to label the Bn with radionuclides by gamma rays. Tat (49-57) is a peptide that across the cell membrane easily so that, when it is conjugated to different proteins, it can works as a Trojan horse, facilitating the drug internalization to the cells. The radiopharmaceutical 99mTc-N2S2-Tat(49-57)-Lys3-Bn was prepared for diagnosis and therapy at early stage of breast cancer. The objective of this study was to determine the role of Tat in the internalization kinetics of radiopharmaceuticals measured by DNA damage induced by means of comet assay. Human lymphocytes were treated with the following protocols: a) Tat-Bn, b) 99mTc-Bn, or c) 99mTc-N2S2-Tat(49-57)-Lys3-Bn, also an untreated group was conformed. The internalization was evaluated at 0, 5, 10, 15, 30 and 60 min after exposure with three repetitions each one, and for radiopharmaceuticals with 2.9, 6.6, 9.0 and 14.8 MBq activities. DNA damage was scored in 100 cells per time and treatment, as tail length and tail moment. A Kruskal-Wallis variance analysis with p≤ 0.05 was applied for comparison between treatments. The results showed that the damage caused by 99mTc-N2S2-Tat(49-57)-Lys3-Bn is significantly higher than that caused by 99mTc-Bn and Tat-Bn, showing that Tat favors the internalization of the radiopharmaceutical. (Author)

  9. Role of neuropeptides in appetite regulation and obesity--a review.

    Science.gov (United States)

    Arora, Sarika; Anubhuti

    2006-12-01

    Obesity represents the most prevalent nutritional problem worldwide which in the long run predisposes to development of diabetes mellitus, hypertension, endometrial carcinoma, osteoarthritis, gall stones and cardiovascular diseases. Despite significant reductions in dietary fat consumption, the prevalence of obesity is on a rise and is taking on pandemic proportions. Obesity develops when energy intake exceeds energy expenditure over time. Recently, a close evolutionary relationship between the peripheral and hypothalamic neuropeptides has become apparent. The hypothalamus being the central feeding organ mediates regulation of short-term and long-term dietary intake via synthesis of various orexigenic and anorectic neuropeptides. The structure and function of many hypothalamic peptides (neuropeptide Y (NPY), melanocortins, agouti-related peptide (AGRP), cocaine and amphetamine regulated transcript (CART), melanin concentrating hormone (MCH), orexins have been characterized in rodent models The peripheral neuropeptides such as cholecystokinin (CCK), ghrelin, peptide YY (PYY3-36), amylin, bombesin regulate important gastrointestinal functions such as motility, secretion, absorption, provide feedback to the central nervous system on availability of nutrients and may play a part in regulating food intake. The pharmacological potential of several endogenous peripheral peptides released prior to, during and/or after feeding are being explored. Long-term regulation is provided by the main circulating hormones leptin and insulin. These systems implicated in hypothalamic appetite regulation provide potential targets for treatment of obesity which could potentially pass into clinical development in the next 5 years. This review summarizes various effects and interrelationship of these central and peripheral neuropeptides in metabolism, obesity and their potential role as targets for treatment of obesity.

  10. Evaluation of the internalization kinetics of the radiopharmaceutical {sup 99m}Tc-N{sub 2}S{sub 2}-Tat(49-57)Lys{sup 3}-Bn with diagnostic purposes, using comet assay; Evaluacion de la cinetica de internalizacion del radiofarmaco {sup 99m}Tc-N{sub 2}S{sub 2}-TAT(49-57)Lys{sup 3}-BN con fines diagnosticos, empleando ensayo cometa

    Energy Technology Data Exchange (ETDEWEB)

    Luna G, M. A.

    2011-07-01

    Gastrin-rea leasing peptide receptors (GRP-r) are over expressed in breast and prostate cancer cells. Bombesin (Bn) binds specifically and strongly to GRP-r and this is the base for to label the Bn with radionuclides by gamma rays. Tat (49-57) is a peptide that across the cell membrane easily so that, when it is conjugated to different proteins, it can works as a Trojan horse, facilitating the drug internalization to the cells. The radiopharmaceutical {sup 99m}Tc-N{sub 2}S{sub 2}-Tat(49-57)-Lys{sup 3}-Bn was prepared for diagnosis and therapy at early stage of breast cancer. The objective of this study was to determine the role of Tat in the internalization kinetics of radiopharmaceuticals measured by DNA damage induced by means of comet assay. Human lymphocytes were treated with the following protocols: a) Tat-Bn, b) {sup 99m}Tc-Bn, or c) {sup 99m}Tc-N{sub 2}S{sub 2}-Tat(49-57)-Lys{sup 3}-Bn, also an untreated group was conformed. The internalization was evaluated at 0, 5, 10, 15, 30 and 60 min after exposure with three repetitions each one, and for radiopharmaceuticals with 2.9, 6.6, 9.0 and 14.8 MBq activities. DNA damage was scored in 100 cells per time and treatment, as tail length and tail moment. A Kruskal-Wallis variance analysis with p{<=} 0.05 was applied for comparison between treatments. The results showed that the damage caused by {sup 99m}Tc-N{sub 2}S{sub 2}-Tat(49-57)-Lys{sup 3}-Bn is significantly higher than that caused by {sup 99m}Tc-Bn and Tat-Bn, showing that Tat favors the internalization of the radiopharmaceutical. (Author)

  11. Multilabel immunofluorescence and antigen reprobing on formalin-fixed paraffin-embedded sections: novel applications for precision pathology diagnosis.

    Science.gov (United States)

    Pan, Jie; Thoeni, Cornelia; Muise, Aleixo; Yeger, Herman; Cutz, Ernest

    2016-06-01

    We report new methods for multilabel immunofluorescence (MIF) and reprobing of antigen epitopes on the same formalin-fixed paraffin-embedded (FFPE) sections. The MIF method includes an antigen-retrieval step followed by multilabel immunostaining and examination by confocal microscopy. As examples, we illustrate epitopes localized to the apical and basolateral membranes, and the cytoplasm of enterocytes of normal small intestine and in cases of congenital enteropathies (microvillous inclusion disease and congenital tufting enteropathy). We also demonstrate localization of the bile salt excretion pump protein (BSEP) in bile canalicular membrane of normal hepatocytes and in cases of primary sclerosing cholangitis. To demonstrate colocalization of cytoplasmic and nuclear epitopes we analyzed normal control and hyperplastic pulmonary neuroendocrine cells (PNEC) and neuroepithelial bodies (NEBs), presumed airway sensors in the lungs of infants with bronchopulmonary dysplasia (BPD). As cytoplasmic markers we used anti-bombesin or anti-synaptic vesicle protein 2 (SV2) antibody, respectively, and for nuclear localization, antibodies against neurogenic genes mammalian achaete-scute homolog (Mash1) and prospero homeobox 1 (Prox1), essential for NEB cells differentiation and maturation, hypoxia-inducible factor 1α (HIF1α) a downstream modulator of hypoxia response and a proliferation marker Ki67. The reprobing method consisted of removal of the previously immunolabeled target and immunostaining with different antibodies, facilitating colocalization of enterocyte brush border epitopes as well as HIF1α, Mash1 and Prox1 in PNEC/NEB PNEC and NEBs. As these methods are suitable for routine FFPE pathology samples from various tissues, allowing visualization of multiple epitopes in the same cells/sections with superior contrast and resolution, they are suitable for a wide range of applications in diagnostic pathology and may be particularly well suited for precision medicine

  12. 糖尿病/星型胶质细胞富集磷蛋白酶-15的表达对急性胰腺炎腺泡细胞凋亡的影响%Effects of diabetes mellitus/astrocyte enriched phosphorus protease 15 expression on the apoptosis of acinar cells in acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    胡明星; 王玉柱; 刘传江; 秦涛

    2015-01-01

    目的 观察糖尿病/星型胶质细胞富集磷蛋白酶-15(PED/PEA-15)的表达对蛙皮素诱导的体外急性胰腺炎(AP)模型腺泡细胞凋亡的影响.方法 建立体外AP模型:用10 nmol/L的蛙皮素处理胰腺腺泡细胞株(AR42J细胞)建立AP模型,4h后检测培养液淀粉酶水平,实时荧光定量反转录聚合酶链反应(RT-PCR)检测PED/PEA-15的mRNA表达,吖啶橙/溴乙锭(AO/EB)法检测AR42J细胞的凋亡.构建PED/PEA-15的真核表达载体pcDNA3和空载体,利用脂质体转染AR42J细胞,72 h后加入10 nmol/L的蛙皮素处理,RT-PCR检测PED/PEA-15的mRNA表达水平,AO/EB法检测AR42J细胞的凋亡.结果 蛙皮素处理的AR42J细胞培养液淀粉酶水平较未处理细胞明显升高[(748.75±42.90) U/L较(249.75±27.16) U/L,P<0.05],PED/PEA-15的mRNA表达降低(5.24±0.66)倍(P<0.05),细胞凋亡率[(78.75±0.03)%]较未处理组[(17.50±0.04)%]升高(P<0.05).PED/PEA-15-pcDNA组AR42J细胞较空载体组PED/PEA-15的mRNA表达升高(4.27±0.78)倍(P<0.05),淀粉酶水平[(528.71±34.92) U/L]较空载体组[(856.29±52.39) U/L]明显下降(P<0.05),细胞凋亡率[(22.19±1.21)%]较空载体组[(68.92±1.83)%]降低(P<0.05),转染空载体组各项指标与未转染组差异无统计学意义(P>0.05).结论 PED/PEA-15蛋白在胰腺腺泡细胞的表达升高,能够抑制蛙皮素诱导的AR42J胰腺腺泡细胞凋亡.%Objective To investigate the effect of diabetes mellitus/astrocyte enriched phosphorus protease 15 (PED/PEA-15) expression on the apoptosis of acinar cells in bombesin-induced acute pancreatitis.Methods A model of acute pancreatitis with bombesin of 10 nmol/L was established.Amylase was determined 4 h later.The real-time reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of PED/PEA-15 mRNA.The pcDNA or empty vehicle was created and transfected into AR42J cells.After the AR42J cells were treated with 10 nmol/L bombesin for 72 h, the

  13. Ligation-based assembly for constructing mouse synthetic scFv libraries by chain shuffling with in vivo-amplified VH and VL fragments.

    Science.gov (United States)

    Nishi, Michiru; Jian, Nan; Yamamoto, Keiko; Seto, Haruyo; Nishida, Yuichi; Tonoyama, Yasuhiro; Shimizu, Nobuyoshi; Nishi, Yoshisuke

    2014-10-01

    In vitro assembly of two or three PCR fragments using primers is a common method of constructing scFv fragments for display on the surface of phage. However, mismatch annealing often occurs during in this step, leading to cloning and display of incomplete Fab or scFv fragments. To overcome this limitation, we developed a ligation-based two-fragment assembly (LTFA) protocol that involved separately cloning VH and Vκ fragments into the high-copy-number plasmid pUC18. The VH and Vκ fragments had randomized complementarity-determining region 3 (CDR3) and were joined with a peptidyl linker composed of (G4S)3. Using this approach, complete sequences of scFv fragments were successfully constructed, and the sequencing of 83 scFv clones revealed that none of the sequences, including the linker region, contained deletions or mutations. In contrast, linker sequences generated using a conventional two-fragment PCR assembly (TFPA) protocol often contained sequence anomalies, including large truncations. Using the LTFA protocol, a final library size of 1.0×10(8)cfu was achieved. Examination of the amino acid profiles of the generated scFv fragments within the randomized regions introduced using degenerate codons did not detect any bias from that expected based on stochastic distribution. After several cycles of panning with this library, antigen-specific scFvs against two reference antigens, hen egg lysozyme and streptavidin were detected. In addition, scFvs with specificity against peptidyl antigens in the loop region of the Medaka ortholog of human C6orf89, which encodes a histone deacetylase enhancer that interacts with the bombesin receptor, were also obtained. The LTFA protocol developed here is robust and allows for the easy construction of integral scFv fragments compared with conventional TFPA. Utilizing LTFA, other CDRs can be readily combined. This approach also allows for the in vitro maturation of scFv fragments by separately introducing randomization in CDRs or

  14. Radio-peptides targeting g-protein coupled receptors in cancer: from bench to bed

    International Nuclear Information System (INIS)

    Full text of publication follows. In the development of targeted imaging and therapy agents the most important challenge and prerequisite is to identify and validate the molecular targets of any disease. The targets should be specific, relevant, easily accessible and highly expressed. In addition they should have no or at least very low expression in normal tissue. Among the many drug targets is the large family of G-protein coupled receptors (GPCRs). It is the most important family of marketed drugs and the basic accomplishments in the field were recognised by the award of the recent Nobel price in chemistry. GPCRs also play a role in cancer. Several of these receptors are massively over-expressed in different human tumors such as neuroendocrine tumors (over-expression of the somatostatin receptor family), prostate and breast tumors (bombesin receptor family), brain tumors (NK1 receptor) etc.. This allows to develop (nuclear, MRI, optical) probes for imaging and potentially targeted therapy (theragnostics). Natural ligands targeting GPCRs are often peptides. They need to be modified for metabolic stability, modified for labeling with radio-metals (conjugation of bifunctional chelators) or radio-halogens (prosthetic groups). Preserved biological integrity after modification and labeling needs to be assured, long retention times in the tumor is important, conferred by internalisation. Radio-metal labeling in particular needs to be reasonably fast and the radio metal complexes have to show high stability with regard to radio-metal release. These prerequisites will be discussed for somatostatin receptor based radio-peptides in particular. For a successful clinical application preclinical imaging and biodistribution in adequate animal models are mandatory. New tracers for positron emission tomography (PET) and single photon emission computed tomography (SPECT) will be presented for neuroendocrine tumors and prostate cancer. In particular radiolabeled antagonists will

  15. Evaluation the influence of Polyethylene glycol in circulation and biodistribution of pH-sensitive liposomes, radiolabeled with Technetium 99m in experimental models

    International Nuclear Information System (INIS)

    Liposomes are lipid vesicles widely studied throughout the world as nanocarriers for different substances. The hydrophilic polymer polyethylene glycol (PEG) might be added onto the surface of liposomes to prolong the circulation time by reducing the opsonization of the vesicles, leading to a reduced uptake by the mononuclear phagocyte system (MPS). Several studies claim that the molecular weight of the PEG, as well as combination of different types of PEG with different molecular weights may alter the pharmacokinetics of the liposome. Therefore, the purpose of this study was to evaluate the influence of molecular weight and PEG combinations with different chain sizes in the pharmacokinetics and biodistribution of pH-sensitive liposomes containing 99mTc-HYNIC-βAla-Bombesin complex (7-14 ) in tumor models (4T1 and Ehrlich). Eight liposomal formulations were prepared, the results showed that the liposomes exhibited adequate chemical and physical-chemical properties, such as mean diameter less than 300nm, monodisperse populations, neutral zeta potential, and encapsulation content of 26.4 to 38.7%. The images obtained by transmission electron cryomicroscopy (cryo-TEM) allowed visualization of unilamellar vesicles with an average diameter of 90 nm. There was no difference in blood half-life (T1/2), thereby for the composition of liposomes used in this study, PEG did not increase blood circulation time. Biodistribution studies and scintigraphic images showed high uptake by organs of the SMF, liver and spleen. The PEG2000 formulation showed higher concentration in blood. Liposomes with DSPE, PEG2000 or PEG1000 / 5000 showed higher uptake in the tumor compared to the contralateral muscle, but there was no statistical difference between the formulations when tumor-to-muscle ratio, obtained in the biodistribution studies or scintigraphic images, was analyzed. The results suggest that for this specific formulation, the addition of PEG was not efficient for increasing the

  16. SU-E-I-82: PET Radiopharmaceuticals for Prostate Cancer Imaging: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, F [Delfin Farmacos e Derivados Ltda, Lauro De Freitas, Bahia (Brazil); Escola Bahiana de Medicina e Saude Publica, Salvador, Bahia (Brazil); Silva, D da [Delfin Farmacos e Derivados Ltda, Lauro De Freitas, Bahia (Brazil); Rodrigues, L [Escola Bahiana de Medicina e Saude Publica, Salvador, Bahia (Brazil)

    2015-06-15

    Purpose: The aim of this work was to review new and clinical practice PET radiopharmaceuticals for prostate cancer imaging. Methods: PET radiopharmaceuticals were reviewed on the main databases. Availability, dosimetry, accuracy and limitations were considered. Results: The following radioisotopes with respective physical half-life and mean positron energy were found: {sup 18}F (109,7 min, 249,8 keV), {sup 89}Zr (78,4 hs, 395,5 keV), {sup 11}C (20,4 min, 385,7 keV) and {sup 68}Ga (67,8 min, 836 keV). {sup 68}Ga was the only one not produced by cyclotron. Radiopharmaceuticals uptake by glucose metabolism ({sup 18}F-FDG), lipogenesis ({sup 11}C-Choline and {sup 11}C-Acetate), amino acid transport (Anti-{sup 18}F-FACBC), bone matrix ({sup 18}F-NaF), prostatespecific membrane antigen ({sup 68}Ga-PSMA and {sup 89}Zr-J591), CXCR receptors ({sup 89}Ga-Pentixafor), adrenal receptors ({sup 18}F-FDHT) and gastrin release peptide receptor (bombesin analogue). Most of radiopharmaceuticals are urinary excretion, so bladder is the critical organ. 11C-choline (pancreas), Anti-{sup 18}FFACBC (liver) and {sup 18}F-FBDC (stomach wall) are the exception. Higher effective dose was seen {sup 18}F-NaF (27 μSv/MBq) while the lowest was {sup 11}CAcetate (3,5 μSv/MBq). Conclusion: Even though {sup 18}F-FDG has a large availability its high urinary excretion and poor uptake to slow growing disease offers weak results for prostate cancer. Better accuracy is obtained when {sup 18}F-NaF is used for bone metastatic investigation although physicians tend to choose bone scintigraphy probably due to its cost and practice. Many guidelines in oncology consider {sup 11}C or {sup 18}F labeled with Choline the gold standard for biochemical relapse after radical treatment. Local, lymph node and distant metastatic relapse can be evaluated at same time with this radiopharmaceutical. There is no consensus over bigger urinary excretion for {sup 18}F labeling. Anti-{sup 18}F-FACBC, {sup 68}Ga-PSMA and {sup

  17. Co-expressed peptide receptors in breast cancer as a molecular basis for in vivo multireceptor tumour targeting

    Energy Technology Data Exchange (ETDEWEB)

    Reubi, Jean Claude; Gugger, Mathias; Waser, Beatrice [Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne (Switzerland)

    2002-07-01

    Breast cancers can express different types of peptide receptors such as somatostatin, vasoactive intestinal peptide (VIP), gastrin-releasing peptide (GRP) and NPY(Y{sub 1}) receptors. The aim of this in vitro study was to evaluate which is the most appropriate peptide receptor or peptide receptor combination for in vivo diagnostic and therapeutic targeting of breast cancers. Seventy-seven primary breast cancers and 15 breast cancer lymph node metastases were investigated in vitro for their expression of somatostatin, VPAC{sub 1}, GRP and NPY(Y{sub 1}) receptors using in vitro receptor autoradiography on successive tissue sections with {sup 125}I-[Tyr{sup 3}]-octreotide, {sup 125}I-VIP, {sup 125}I-[Tyr{sup 4}]-bombesin and {sup 125}I-[Leu{sup 31},Pro{sup 34}]-PYY respectively. This study identified two groups of tumours: a group of 68 tumours (88%) with at least one receptor expressed at high density (>2,000 dpm/mg tissue) that may provide a strong predictive value for successful in vivo targeting, and a group of nine tumours (12%) with no receptors or only a low density of them (<2,000 dpm/mg tissue). In the group with high receptor density, 50 of the 68 tumours (74%) expressed GRP receptors, 45 (66%) expressed NPY(Y{sub 1}) receptors, 25 (37%) expressed VPAC{sub 1} receptors and 14 (21%) expressed somatostatin receptors. Mean density was 9,819{+-}530 dpm/mg tissue for GRP receptors, 9,135{+-}579 dpm/mg for NPY(Y{sub 1}) receptors, 4,337{+-}528 dpm/mg for somatostatin receptors and 3,437{+-}306 dpm/mg for VPAC{sub 1} receptors. It is of note that tumours expressing NPY(Y{sub 1}) or GRP receptors, or both, were found in 63/68 (93%) cases. Lymph node metastases showed a similar receptor profile to the corresponding primary tumour. This in vitro study strongly suggests that the combination of radiolabelled GRP and Y{sub 1} analogues should allow targeting of breast carcinomas and their lymph node metastases for in vivo peptide receptor scintigraphy and radiotherapy

  18. Evaluation the influence of Polyethylene glycol in circulation and biodistribution of pH-sensitive liposomes, radiolabeled with Technetium 99m in experimental models; Avaliacao da influencia do polietilenoglicol na circulacao e biodistribuicao de lipossomas pH-sensiveis, radiomarcados com Tecnecio 99m em modelos experimentais

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Shirleide Santos

    2016-07-01

    Liposomes are lipid vesicles widely studied throughout the world as nanocarriers for different substances. The hydrophilic polymer polyethylene glycol (PEG) might be added onto the surface of liposomes to prolong the circulation time by reducing the opsonization of the vesicles, leading to a reduced uptake by the mononuclear phagocyte system (MPS). Several studies claim that the molecular weight of the PEG, as well as combination of different types of PEG with different molecular weights may alter the pharmacokinetics of the liposome. Therefore, the purpose of this study was to evaluate the influence of molecular weight and PEG combinations with different chain sizes in the pharmacokinetics and biodistribution of pH-sensitive liposomes containing {sup 99m}Tc-HYNIC-βAla-Bombesin complex (7-14 ) in tumor models (4T1 and Ehrlich). Eight liposomal formulations were prepared, the results showed that the liposomes exhibited adequate chemical and physical-chemical properties, such as mean diameter less than 300nm, monodisperse populations, neutral zeta potential, and encapsulation content of 26.4 to 38.7%. The images obtained by transmission electron cryomicroscopy (cryo-TEM) allowed visualization of unilamellar vesicles with an average diameter of 90 nm. There was no difference in blood half-life (T1/2), thereby for the composition of liposomes used in this study, PEG did not increase blood circulation time. Biodistribution studies and scintigraphic images showed high uptake by organs of the SMF, liver and spleen. The PEG2000 formulation showed higher concentration in blood. Liposomes with DSPE, PEG2000 or PEG1000 / 5000 showed higher uptake in the tumor compared to the contralateral muscle, but there was no statistical difference between the formulations when tumor-to-muscle ratio, obtained in the biodistribution studies or scintigraphic images, was analyzed. The results suggest that for this specific formulation, the addition of PEG was not efficient for increasing

  19. Development of a specific radiopharmaceutical based on gold nanoparticles functionalized with HYNIC-peptide/mannose for the sentinel lymph node detection in breast cancer; Desarrollo de un radiofarmaco especifico basado en nanoparticulas de oro funcionalizadas con HYNIC-peptido/manosa para la deteccion de ganglio centinela en cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Ocampo G, B. E.

    2012-07-01

    ) which was retained during 24 h with minimal kidney accumulation (0.98 {+-} 0.10% Id) and negligible uptake in all other tissues. In order to design a pharmaceutical formulation for the instant preparation of stable m ultimeric systems with target-specific molecular recognition based on gold nanoparticles, a freeze-dried kit formulation of {sup 99m}Tc-ethylenediamine-N, N-diacetic acid (EDDA)/hydrazino nicotinyl (HYNIC)-Tyr{sup 3}-octreotide ({sup 99m}Tc-EDDA/HYNIC-TOC, previously approved by the Mexican Ministry of Health) (vial 1) and a second vial containing 1.5 ml of Au-Np solution plus 10 {mu}L of thiol-mannose, Lys{sup 3}-bombesin, or cyclo[Arg-Gly-Asp-D-Phe-Lys-(Cys)] (c[RGDfK(C)] (approximately 285 molecules per Au-Np) (vial 2) were prepared. M ultimeric radiopharmaceuticals prepared from kit showed a radiochemical purity of 96 {+-} 2%. The far-infrared spectra showed a characteristic band at 279 {+-} 1 cm{sup -1}, which was assigned to the Au-S bond. UV-Vis and XP S also indicated that the Au-Np were functionalized with peptides or mannose. Radiopharmaceuticals showed specific recognition for receptors expressed in cancer cells or rat liver cells. Micro-SPECT/CT images showed clear tumour uptake and lymph node accumulation. The kit demonstrated excellent stability during storage at 4 C for 6 months. This study demonstrated that {sup 99m}Tc-Au-Np-mannose remains within the first lymph node during 24 h and therefore might be useful as a target-specific radiopharmaceutical for SLND using 1-day or 2-day conventional protocols. Likewise, m ultimeric systems of {sup 99m}Tc-Au-Np-mannose, {sup 99m}Tc-Au-Np-RGD and {sup 99m}Tc-Au-Np-Lys{sup 3}-bombesin prepared from kits exhibited properties suitable as target-specific agents for molecular imaging of tumours and sentinel lymph node. (Author)

  20. Development of a specific radiopharmaceutical based on gold nanoparticles functionalized with HYNIC-peptide/mannose for the sentinel lymph node detection in breast cancer

    International Nuclear Information System (INIS)

    kidney accumulation (0.98 ± 0.10% Id) and negligible uptake in all other tissues. In order to design a pharmaceutical formulation for the instant preparation of stable m ultimeric systems with target-specific molecular recognition based on gold nanoparticles, a freeze-dried kit formulation of 99mTc-ethylenediamine-N, N-diacetic acid (EDDA)/hydrazino nicotinyl (HYNIC)-Tyr3-octreotide (99mTc-EDDA/HYNIC-TOC, previously approved by the Mexican Ministry of Health) (vial 1) and a second vial containing 1.5 ml of Au-Np solution plus 10 μL of thiol-mannose, Lys3-bombesin, or cyclo[Arg-Gly-Asp-D-Phe-Lys-(Cys)] (c[RGDfK(C)] (approximately 285 molecules per Au-Np) (vial 2) were prepared. M ultimeric radiopharmaceuticals prepared from kit showed a radiochemical purity of 96 ± 2%. The far-infrared spectra showed a characteristic band at 279 ± 1 cm-1, which was assigned to the Au-S bond. UV-Vis and XP S also indicated that the Au-Np were functionalized with peptides or mannose. Radiopharmaceuticals showed specific recognition for receptors expressed in cancer cells or rat liver cells. Micro-SPECT/CT images showed clear tumour uptake and lymph node accumulation. The kit demonstrated excellent stability during storage at 4 C for 6 months. This study demonstrated that 99mTc-Au-Np-mannose remains within the first lymph node during 24 h and therefore might be useful as a target-specific radiopharmaceutical for SLND using 1-day or 2-day conventional protocols. Likewise, m ultimeric systems of 99mTc-Au-Np-mannose, 99mTc-Au-Np-RGD and 99mTc-Au-Np-Lys3-bombesin prepared from kits exhibited properties suitable as target-specific agents for molecular imaging of tumours and sentinel lymph node. (Author)

  1. Multi-functional system of radiotherapy and thermal phototherapy for tumors that over-express receptors of the gastrin releasing peptide

    International Nuclear Information System (INIS)

    The aim of this research was to prepare and characterize a multifunctional system of 177Lu and 99mTc-labelled gold nanoparticles conjugated to Tat(49 57)-Lys3 bombesin (177Lu/99mTc- AuNP-Tat-Bn) and to evaluate the radiation absorbed dose in GRP receptor positive PC3 tumours induced in mice (human prostate cancer cells), as well as to evaluate the thermal effect produced by the multifunctional system in PC3 cancer cells. The preparation of the system involved the conjugation of Bn-Tat, DOTA-GGC and HYNICTOC peptides to AuNP of 20 nm or 5 nm in diameter. The radiolabeling of the system with 99mTc was carried out through the ligand HYNIC-TOC and with the 177Lu through DOTA-GGC. The functionalization of peptides to AuNP, was accomplished through a spontaneous reaction of thiol groups. The system was characterized by spectroscopic techniques while radiochemical purity was determined by size-exclusion molecular chromatography and ultrafiltration. Various internalization trials and non-specific binding were tested to demonstrate the affinity of the system to PC3 cells. The thermal effect was evaluated incubating the system into PC3 cells and irradiating it with a Nd:YAG pulsed laser beam and monitoring the temperature; after irradiation, cell viability was measured. In the evaluation of absorbed dose in mice with induced tumours, the system was administered intratumorally and later, mice were sacrificed, relevant organs and tumor were extracted, activity was quantified and radiopharmaceutical models were obtained for each organ and tumor to be used in the accumulated activity and absorbed dose calculation by the MIRD methodology. Finally, to establish the system location at cellular level, fluorescent images of the system incubated in PC3 cells were acquired with an epi fluorescent microscope. Tem, UV-Vis, XP S and Far-IR spectroscopy techniques demonstrated that AuNPs were functionalized with peptides through interactions with the -Sh groups. The radiochemical purity

  2. Use of 99mTc-HYNIC-βAla-Bombesina(7-14) peptide for the identification of prostate tumor, LNCaP line, in an experimental model

    International Nuclear Information System (INIS)

    Prostate cancer is one of the most prevalent tumors in men, showing high mortality rates. Current diagnostic methods are not able to identify early prostate carcinoma, often resulting in a late diagnosis with established metastasis. Thus, there is by the scientific community an incessant search for diagnostic methods for early assessment of prostate cancer, facilitating the treatment and increasing the chances of cure. In this context, nuclear medicine provides a diagnostic method which can detect tumors at an early stage, because it is based on biochemical and physiological changes of the tissue, such as overexpression of gastrin releasing peptide receptors (GRPr's) by prostate cancer cells. Bombesin, a tetradecapeptide isolated from the frog Bombina bombina, has a high affinity for the GRPr's, since it is analogous to gastrin releasing peptide. Therefore, this study aims to prepare the complex 99mTc-HYNIC-βAla-Bombesina(7-14) and use it for the identification of prostate tumor, LNCaP line, in an experimental model. For in vitro assays, aliquots of 0.026 MBq of the radiopeptide were incubated with 2x106 LNCaP cells in a water bath at 37 deg C, for 1 and 4 hours, with and without prior addition of cold peptide (n=3). Prostate tumors were induced into the upper right flank of male BALB/c nude mice by subcutaneous injection of 5x106 LNCaP cells resuspended in 150 μL of Matrigel:RPMI-1640 medium (1:1). Biodistribution profile (n=5) and scintigraphic images (n=3) were obtained at 1 and 4 hours after intravenous injection of 7.4 MBq of 99mTc-HYNIC-βAla-Bombesina(7-14). To assess this, healthy male BALB/c mice and tumor-bearing male BALB/c nude mice with 15, 20 and 25 days of tumor development were used. In vitro study results showed that the fraction of the radiopeptide which bound to LNCaP cells was 2.08 +- 0.30% (1 hour) and 2.44 +- 0.18% (4 hours). From the percentage which was bound, the internalized fractions were 25.64 +- 3.14% (1 hour) and 25.27 +- 2.05% (4

  3. Multi-functional system of radiotherapy and thermal phototherapy for tumors that over-express receptors of the gastrin releasing peptide; Sistema multifuncional de radioterapia y fototerapia termica para tumores que sobre-expresan receptores del peptido liberador de gastrina

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez M, N. P.

    2014-07-01

    The aim of this research was to prepare and characterize a multifunctional system of {sup 177}Lu and {sup 99m}Tc-labelled gold nanoparticles conjugated to Tat(49 57)-Lys{sup 3} bombesin ({sup 177}Lu/{sup 99m}Tc- AuNP-Tat-Bn) and to evaluate the radiation absorbed dose in GRP receptor positive PC3 tumours induced in mice (human prostate cancer cells), as well as to evaluate the thermal effect produced by the multifunctional system in PC3 cancer cells. The preparation of the system involved the conjugation of Bn-Tat, DOTA-GGC and HYNICTOC peptides to AuNP of 20 nm or 5 nm in diameter. The radiolabeling of the system with {sup 99m}Tc was carried out through the ligand HYNIC-TOC and with the {sup 177}Lu through DOTA-GGC. The functionalization of peptides to AuNP, was accomplished through a spontaneous reaction of thiol groups. The system was characterized by spectroscopic techniques while radiochemical purity was determined by size-exclusion molecular chromatography and ultrafiltration. Various internalization trials and non-specific binding were tested to demonstrate the affinity of the system to PC3 cells. The thermal effect was evaluated incubating the system into PC3 cells and irradiating it with a Nd:YAG pulsed laser beam and monitoring the temperature; after irradiation, cell viability was measured. In the evaluation of absorbed dose in mice with induced tumours, the system was administered intratumorally and later, mice were sacrificed, relevant organs and tumor were extracted, activity was quantified and radiopharmaceutical models were obtained for each organ and tumor to be used in the accumulated activity and absorbed dose calculation by the MIRD methodology. Finally, to establish the system location at cellular level, fluorescent images of the system incubated in PC3 cells were acquired with an epi fluorescent microscope. Tem, UV-Vis, XP S and Far-IR spectroscopy techniques demonstrated that AuNPs were functionalized with peptides through interactions with

  4. Synthesis and biological evaluation of copper-64 radiolabeled [DUPA-6-Ahx-(NODAGA)-5-Ava-BBN(7-14)NH2], a novel bivalent targeting vector having affinity for two distinct biomarkers (GRPr/PSMA) of prostate cancer

    International Nuclear Information System (INIS)

    Gastrin-releasing peptide receptors (GRPr) and prostate-specific membrane antigen (PSMA) are two identifying biomarkers expressed in very high numbers on prostate cancer cells and could serve as a useful tool for molecular targeting and diagnosis of disease via positron-emission tomography (PET). The aim of this study was to produce the multipurpose, bivalent [DUPA-6-Ahx-(64Cu-NODAGA)-5-Ava-BBN(7-14)NH2] radioligand for prostate cancer imaging, where DUPA = (2-[3-(1,3-dicarboxypropyl)-ureido]pentanedioic acid), a small-molecule, PSMA-targeting probe, 6Ahx = 6-aminohexanoic acid, 5-Ava = 5-aminovaleric acid, NODAGA = [2-(4,7-biscarboxymethyl)-1,4,7-(triazonan-1-yl)pentanedioic acid] (a derivative of NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid)), and BBN(7-14)NH2 = bombesin, a GRPr-specific peptide targeting probe. Methods: The PSMA/GRPr dual targeting ligand precursor [DUPA-6-Ahx-K-5-Ava-BBN(7-14)NH2], was synthesized by solid-phase and manual peptide synthesis, after which NODAGA was added via manual conjugation to the ε-amine of lysine (K). The new bivalent GRPr/PSMA targeting vector was purified by reversed-phase high performance liquid chromatography (RP-HPLC), characterized by electrospray-ionization mass spectrometry (ESI-MS), and metallated with 64CuCl2 and natCuCl2. The receptor binding affinity was evaluated in human, prostate, PC-3 (GRPr-positive) and LNCaP (PSMA-positive) cells and the tumor-targeting efficacy determined in severe combined immunodeficient (SCID) and athymic nude mice bearing PC-3 and LNCaP tumors. Whole-body maximum intensity microPET/CT images of PC-3/LNCaP tumor-bearing mice were obtained 18 h post-injection (p.i.). Results: Competitive binding assays in PC-3 and LNCaP cells indicated high receptor binding affinity for the [DUPA-6-Ahx-(natCu-NODAGA)-5-Ava-BBN(7-14)NH2] conjugate. MicroPET scintigraphy in PC-3/LNCaP tumor-bearing mice indicated that xenografted tumors were visible at 18 h p.i. with collateral, background

  5. Production and Clinical Applications of Radiopharmaceuticals and Medical Radioisotopes in Iran.

    Science.gov (United States)

    Jalilian, Amir Reza; Beiki, Davood; Hassanzadeh-Rad, Arman; Eftekhari, Arash; Geramifar, Parham; Eftekhari, Mohammad

    2016-07-01

    During past 3 decades, nuclear medicine has flourished as vibrant and independent medical specialty in Iran. Since that time, more than 200 nuclear physicians have been trained and now practicing in nearly 158 centers throughout the country. In the same period, Tc-99m generators and variety of cold kits for conventional nuclear medicine were locally produced for the first time. Local production has continued to mature in robust manner while fulfilling international standards. To meet the ever-growing demand at the national level and with international achievements in mind, work for production of other Tc-99m-based peptides such as ubiquicidin, bombesin, octreotide, and more recently a kit formulation for Tc-99m TRODAT-1 for clinical use was introduced. Other than the Tehran Research Reactor, the oldest facility active in production of medical radioisotopes, there is one commercial and three hospital-based cyclotrons currently operational in the country. I-131 has been one of the oldest radioisotope produced in Iran and traditionally used for treatment of thyrotoxicosis and differentiated thyroid carcinoma. Since 2009, (131)I-meta-iodobenzylguanidine has been locally available for diagnostic applications. Gallium-67 citrate, thallium-201 thallous chloride, and Indium-111 in the form of DTPA and Oxine are among the early cyclotron-produced tracers available in Iran for about 2 decades. Rb-81/Kr-81m generator has been available for pulmonary ventilation studies since 1996. Experimental production of PET radiopharmaceuticals began in 1998. This work has culminated with development and optimization of the high-scale production line of (18)F-FDG shortly after installation of PET/CT scanner in 2012. In the field of therapy, other than the use of old timers such as I-131 and different forms of P-32, there has been quite a significant advancement in production and application of therapeutic radiopharmaceuticals in recent years. Application of (131)I