Amino acid sequences of three canine bombesin-like peptides were determined after sequential purification of an extract obtained from 820 g of intestinal muscle. These three peptides contained 27, 23, and 10 amino acid residues. The sequences of the two shorter forms were identical to the corresponding carboxyl-terminal sequence of the heptacosapeptide. The sequence of the largest peptide is H2...

The ability of the mitogenic peptide bombesin and other growth factors to trigger and support early development of the inner ear was studied on chick embryo otocysts in culture. The normal pattern of development was preserved in cultured otic vesicles in the presence of 20% fetal calf serum in the medium. Differentiation proceeded from stage 18 to 22 during the first 24 h and further to stage 2...

Female Syrian golden hamsters with N-nitrosobis(2-oxopropyl)amine-induced pancreatic cancers were treated for 2 months with new pseudononapeptide bombesin receptor antagonist [D-Tpi6,Leu13 psi (CH2NH)-Leu14]bombesin(6-14)(RC-3095), administered s.c. with implanted osmotic minipumps releasing 20 micrograms/day of the analogue. The results were compared to those obtained by treatment with somatos...

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 peptid...

Bombesin administered subcutaneously to rats, three times daily for four days, induces pancreatic growth at a dose of 10 micrograms/kg. Growth was characterised by an increased pancreatic weight and content in protein and RNA, accompanied by cellular hypertrophy. Chronic bombesin also enhanced the pancreatic content in chymotrypsin and to a lesser degree its contents in amylase and lipase. The ...

Desensitization is a process of adaptation by cells to a stimulus. It is characterised by a decrease in responsiveness of the cell and may be receptor-specific (homologous) or receptor-nonspecific (heterologous). Desensitization has been described for most receptor classes and for each of the second messenger systems [I-31. However, although agonist-induced desensitization has been observed in ...

The binding of (Y-Ty#)bombesin to rat brain slices was investigated. Radiolabeled (Tyr4)bombesin bound with high affinity (Kd = 4 nM) to a single class of sites (B,,, = 130 fmol/mg of protein); the ratio of specific to nonspecific binding was 6/l. Also, pharmacology studies indicated that the C-terminal of bombesin was important for the high affinity binding activity. Autoradiographic studies i...

The effect of bombesin on insulin and gastrin response to a standard labelled meal was studied in eight healthy male volunteers. The gastric emptying of solids was simultaneously evaluated. During intravenous infusion of the peptide (5 ng/kg/min) the insulin release after eating was greatly reduced whereas food stimulated gastrin release was significantly enhanced. Both effects of bombesin are ...

The effects of somatostatin analogue RC-160 and bombesin/gastrin releasing-peptide (GRP) antagonist RC-3095 were evaluated in Copenhagen rats bearing the anaplastic, androgen-independent Dunning R3327-AT-1 prostatic adenocarcinoma. In the first experiment, RC-160 was given in the form of microcapsules releasing 60 micrograms/day/rat. RC-3095 was administered from implanted Alzet osmotic minipum...