RT info:eu-repo/semantics/article
T1 Bombesin induces a reduction of somatostatin inhibition of adenylyl cyclase activity, Gi function, and somatostatin receptors in rat exocrine pancreas
A1 Álvaro Alonso, Itziar
A1 Muñoz Acedo, Gema
A1 Rodríguez Martín, Eulalia
A1 Schally, Andrew Victor
A1 Arilla Ferreiro, Eduardo
K1 Bombesin
K1 RC-3095
K1 Proglumide
K1 Somatostatin receptor
K1 G-protein
K1 Adenylyl cyclase
K1 Bioquímica
K1 Biochemistry
K1 Science
K1 Ciencia
AB To analyze the effect of bombesin on the somatostatin (SS) mechanism of action in the exocrine pancreas, male Wistar rats (250-270 g) were injected intraperitoneally with bombesin (10 ¿g/kg) three times daily at 8-h intervals for 7 or 14 days. Bombesin attenuated the ability of SS to inhibit forskolin-stimulated adenylyl cyclase activity in pancreatic acinar membranes. However, it did not decrease the ability of forskolin to stimulate the adenylyl cyclase catalytic subunit. The ability of 5'-guanylylimidodiphosphate [Gpp(NH)p] (a nonhydrolyzable GTP analog) to inhibit forskolin-stimulated adenylyl cyclase activity was diminished in pancreatic acinar cell membranes from bombesin-treated rats. Bombesin administration did not affect the ADP-ribosylation of a 41-kDa G protein catalyzed by pertussis toxin. The maximal SS binding capacity of pancreatic acinar membranes from bombesin-treated rats was decreased when compared with controls at the two time periods studied. The bombesin/gastrin-releasing peptide antagonist [D-Tpi6,Leu13¿(CH2NH)Leu14]bombesin (6-14) (RC-3095) (10 ¿g/kg ip), injected three times daily at 8-h intervals for 7 or 14 days, had a similar effect to that of bombesin on the SS mechanism of action. The combined administration of bombesin and its antagonist RC-3095 had a greater effect on the SS receptor-effector system than when administered separately. The present study indicates that the pancreatic SS receptor-effector system may be regulated by bombesin in vivo.
PB Elsevier
SN 0196-9781
YR 1999
FD 1999
LK http://hdl.handle.net/10017/2361
UL http://hdl.handle.net/10017/2361
LA eng
DS MINDS@UW
RD 30-nov-2023