Effects of Sauvagine, Urotensin I and CRF on Food Intake in Rats

Sauvagine (SV) is a forty amino acid peptide, isolated from the skin of the South American frog Phyllomedusa sauvagei and structurally related to fish Urotensin I (U1) and to mammalian corticotropin releasing factor (CRF). Intracerebroventricular (ICV) injections of SV (0.3-2.0 micrograms/rat), CRF (1.0-15.0 micrograms/rat) and U1 (0.5-2.0 micrograms/rat) inhibited feeding in 18 hr food deprived rats. By subcutaneous (SC) route, only SV (3.0-10.0 micrograms/kg) and U1 (10.0-20.0 micrograms/kg) exhibited anorexogenic effects, CRF being completely inactive up to a dose of 200 micrograms/kg. Vagotomy did not prevent the feeding inhibition by SC SV. In ICV injected rats, CRF increased grooming in comparison with both food deprived and satiated controls, while SV and U1 increased grooming only in comparison with fasted controls. Compared to satiated animals, food deprived rats when injected ICV with anorexogenic doses of the peptides showed decreased resting and increased moving. Rats given SC injections of SV and U1 significantly decreased grooming in comparison with both food deprived and satiated controls, while increased resting only in comparison with fasted controls. CRF by the SC route did not affect the behaviour of the rat.