Renal nerve inhibition by central NaCl and ANG II is abolished by lesions of the lamina terminalis

Abstract

The lamina terminalis is situated in the anterior wall of the third ventricle and plays a major role in fluid and electrolyte homeostasis and cardiovascular regulation. The present study examined whether the effects of intracerebroventricular infusion of hypertonic saline and ANG II on renal sympathetic nerve activity (RSNA) were mediated by the lamina terminalis. In control, conscious sheep (n = 5), intracerebroventricular infusions of 0.6 M NaCl (1 ml/h for 20 min) and ANG II (10 nmol/h for 30 min) increased mean arterial pressure (MAP) by 6 +/- 1 (P < 0.001) and 14 +/- 3 mmHg (P < 0.001) and inhibited RSNA by 80 +/- 6 (P < 0.001) and 89 +/- 7% (P < 0.001), respectively. Both treatments re..