Anteroventral third ventricle periventricular ablation: Temporary adipsia and persisting thirst deficits

Bilaterally symmetrical periventricular lesions at preoptic-anterior hypothalamic levels of anteroventral third ventricle (AV3V) produce adipsia without aphagia in the rat. Sweet palatable fluids, but not water, are drunk during the adipsic period and if hydration is thus maintained, voluntary ingestion of plain water returns within 10 days. After recovery of spontaneous water drinking, drinking evoked by peripheral angiotensin or hypertonic NaCl thirst challenges is depressed whereas drinking evoked by hypovolemia or feeding after deprivation are unaltered. These results demonstrate a critical role for AV3V in control of water intake, and support the hypothesis that AV3V neural elements function to transduce angiotensin and osmotic hydrational stimuli.