Increased cardiac sympathetic nerve activity in ovine heart failure is reduced by lesion of the area postrema, but not lamina terminalis

Abstract

Increased cardiac sympathetic nerve activity (CSNA) is a key feature of heart failure (HF) and is associated with poor outcome. There is evidence that central angiotensinergic mechanisms contribute to the increased CSNA in HF, but the central sites involved are unknown. In an ovine, rapid pacing model of HF, we investigated the contribution of the lamina terminalis and area postrema to the increased CSNA and also the responses to fourth ventricular infusion of the angiotensin type 1 receptor antagonist losartan. Ablation of the area postrema or sham lesion (n = 6/group), placement of lamina terminalis lesion electrodes (n = 5), and insertion of a cannula into the fourth ventricle (n = 6) wer..