[The pharmacologic analysis of modulated substance P induced by stimulation of the lateral hypothalamus].

The present investigation was undertaken to examine the neurochemical mechanisms of the modulatory effect of substance P (SP) on feeding behavior induced by threshold electrical stimulation of the lateral hypothalamus (LH) in rabbits. The administration of SP, 15 nmol, was found to transform feeding induced by stimulation of LH into escape. The phenomenon was shown to begin at min 20, and to last up to min 60 after SP injection. In the experiments, some antagonists of classic neurotransmitters were injected into the marginal vein of the rabbit ear. An important role of catecholaminergic and M-cholinergic formations in the brain in the SP transformation of their feeding behavior into escape was found in electric stimulation of LH. H-cholinergic and GABA-ergic antagonists produced no effect on the modulatory effect of SP.