Abstract |
Intracerebroventricular (i.c.v.) injections of bombesin (BN) and gastrin-releasing peptide (GRP) dose-dependently decreased food intake in male Wistar rats fasted for 17 h. Neuromedin B (NMB) did not show any effect on food intake. After BN administration, locomotor activity did not significantly change, compared with a vehicle-injected group. The anorexia induced by BN (0.3 microg) was perfectly inhibited by pretreatment with a GRP-receptor antagonist, [D-Tyr(6)]BN(6-13) methyl ester (10 microg), an NO synthase inhibitor, L-nitro- arginine (30 microg), and a PKG inhibitor, H-9 (2 microg). The cGMP concentration in the hypothalamus increased 1 h after administration when compared with the vehicle-injected group. On the other hand, an NMB-receptor antagonist, BIM23127 (10 microg), and the protein kinase (PK) C inhibitors, chelerythrine (2 microg) and Go6983 (2 microg), inhibited only the late phase of the anorexia. A PKC activator, phorbol 12, 13-dibutyrate (3 microg), injected into the ventricle decreased food intake. These findings suggest that BN suppresses food intake mainly mediated through the GRP receptor and NO-cGMP-PKG pathway, and NMB receptor and PKC is partly involved in the late phase of the anorexia.
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Authors | Hiromi Tsushima, Mayumi Mori |
Journal | Pharmacology, biochemistry, and behavior
(Pharmacol Biochem Behav)
Vol. 80
Issue 2
Pg. 289-96
(Feb 2005)
ISSN: 0091-3057 [Print] United States |
PMID | 15680182
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Gastrin-Releasing Peptide
- Bombesin
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Topics |
- Animals
- Anorexia
(chemically induced)
- Bombesin
(administration & dosage)
- Eating
(drug effects, physiology)
- Gastrin-Releasing Peptide
(administration & dosage)
- Lateral Ventricles
(drug effects, physiology)
- Male
- Microinjections
(methods)
- Motor Activity
(drug effects, physiology)
- Rats
- Rats, Wistar
- Telencephalon
(drug effects, physiology)
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