Previously, calcitonin gene-related peptide (CGRP) decreased food inta
ke when administered ICV but not when administered peripherally to rat
s. Amylin, which has a close structural homology to CGRP, reduced food
intake administered IP at concentrations higher than those previously
tested for CGRP. We examined the effects of higher doses of IP-admini
stered CGRP on food intake. CGRP reduced food intake from 25 to 200 mu
g/kg in mice. CGRP did not reduce water intake and was not aversive i
n a two-bottle test. Using a lever press, CGRP was more effective at r
educing milk consumption in prefed than in nonprefed mice. The effect
of CGRP on food intake was not antagonized by the cholecystokinin A re
ceptor antagonist, L364,718. These studies suggest a role for CGRP as
a satiating factor.