Regulatory impairments following selective kainic acid lesions of the neostriatum.

Kainic acid lesions were made to the anteromedial (AMC) or ventrolateral (VLC) caudate nucleus and the projection areas of medial and sulcal prefrontal cortex (PFC), respectively. By the second day following lesion, all control and AMC rats had recovered normal food and water intake. By contrast, VLC lesions resulted in severe aphagia and adipsia lasting 3-15 days, accompanied by a rapid loss in weight. Animals were kept alive by palatable food supplement and force-feeding as required. Once all animals had recovered normal food and water intake (3-5 weeks) drinking to various physiological challenges--5% hypertonic saline s.c., food deprivation, quinine adulteration of water and 40% polyethylene glycol--were found to be normal in both lesion groups. By 3 months after lesion the groups did not differ in weight. Acute aphagia and adipsia had been reported following ablation of the sulcal but not the medial PFC in rats. The present experiment obtains parallel results in the PFC projection areas within the neostriatum.