Involvement
of Nitric Oxide in the Ameliorative Effect of Vasoactive Intestinal
Peptide on Impaired Performance Induced in Rats by Scopolamine
in Radial-Arm Maze by Yoshimasa Yamaguchi, Masaya Higashi, Hidestu Kobayashi
Abstract
A
single intrapentoneal (IP) injection of vasoactive intestinal
peptide (VIP) (65 (µg/kg) had ameliorative effects on impaired
performance induced in rats by scopolamine in a radial-arm maze.
This effect of VIP was nullified when NG-nitro-L-arginine methyl
ester (L-NAME), a specific inhibitor of nitric oxide (NO)-synthase,
was given singly at doses of 50 or 100 mg/kg in combination
with VIP These results suggest that the ameliorative action
of VIP may be partly due to an increase of cerebral blood flow
mediated by NO, which is an endothelium-derived relaxing factor
in blood vessels.