Motor activity and alimentary behavior after radio-frequency and 6-OHDA lesions of lateral hypothalamus and substantia nigra in cats.

Effects of radio-frequency lesions or injections of 6-hydroxydopamine (6-OHDA) into far-lateral hypothalamus (FLH) and substantia nigra (SN) on feeding behavior and motor activity were studied in four groups of cats. Hypoactivity, aphagia and adipsia followed by gradual recovery of alimentary behavior were observed only after radio- frequency lesions of FLH (group I). 6-OHDA injections into FLH evoked only slight and transient disturbances in regulation of fluid intake (group II). Radio-frequency destructions of SN produced long-lasting drop in drinking (group III) while 6-OHDA injections into SN caused long- lasting fall in food consumption (group IV). In both groups with SN damages different pattern of alimentary behavior was accompanied by motor hyperactivity.