Interruption of the Maintenance Phase Of Established Hypertension by Ablation of the Anteroventral Third Ventricle (AV3V) in Rats

Ablation of tissue surrounding anteroventral third ventricle (AV3V) was studied in three models of hypertensive rats. Lesions were placed in the AV3V at one and six weeks following the initiation of one kidney Grollman renal hypertension. At one week the rise in blood pressure was arrested and water intake was reduced; at six weeks arterial pressure returned to prehypertensive levels in animals surviving the post-lesion hydrational crisis. In two kidney (one clip) Goldblatt animals lesioned two weeks post-clip, arterial pressure was significantly reduced but did not become fully normotensive. Finally, the AV3V was also lesioned in spontaneously hypertensive rats (SHR-Okamoto strain) with established hypertension. The lesion did not reduce arterial pressure in adult SHR although characteristic initial adipsia and weight loss occurred. Ablation of the AV3V thus altered the course of maintenance of renal hypertension; however, the arterial pressure of SHR was not affected.