[Visual evoked potentials and water deprivation of rats during intrahypothalamic application of substance P]

Visually evoked potentials (VEP) were recorded in the visual cortex, the dorsal geniculate nucleus and the lateral hypothalamus of satiated and water-deprived rats with and without additional drinking sounds to strengthen motivation and were compared with those during substance-P-injections. Differences in VEP and corresponding spatial and temporal interrelationships of these areas were found by using the method of coincidence of single VEP. Variations of drinking behaviour, weight loss and motor activity were recorded. The findings are discussed with regard to SP and its function as a "regulid peptide".