Regulatory changes following kainic acid-induced striatal lesions.

Kainic acid-induced lesions (KAL) of the striatum produce body weight and regulatory deficits in the rat. Unlike lateral hypothalamic rats. KAL rats drink more during food deprivation and eat more afterwards as compared to both baseline conditions and control rats. The present study investigated these effects further. As in previous studies, food deprivation was found to cause polydipsia and increased postdeprivational food intake in the KAL animal. Urination and defecation, often used as an index of emotionality, were also found to increase under these conditions. When the antidiuretic hormone vasopressin was injected, all of these differences remained with the exception of postdeprivational feeding--KAL rats no longer ate more than controls. These findings suggest that psychogenic factors--but not hormonal influences--may play a primary role in the regulatory peculiarities seen in the KAL rat.