Lesion of A2 noradrenergic neurons with nanoinjections of anti-DβH-saporin into the NTS.

<p>Number and average (mean ± S.E.M.) of TH-positive cells in 40-µm-thick sections from the dorsal (A) and the ventrolateral medulla (B). Sections were taken from 1.9 mm rostral to the obex to 1.9 mm caudal to the obex in animals submitted to A2 or sham lesions. Bilateral nanoinjections of anti-DβH-saporin into the NTS produced a loss of TH-containing neurons in this area (A2 group, loss = 70%; C2 group, loss = 34%), in the RVLM (C1 group, loss = 11%) and in the CVLM (A1 group, loss = 16%). † p<0.05 compared with sham lesion.</p

Effects of A2 noradrenergic neuron lesions on cardiovascular and autonomic responses induced by hypernatremia.

<p>Effects of infusion of hypertonic saline (3 M NaCl, 1.8 ml·Kg⁻¹ body weight) on mean arterial pressure (Δ MAP; A), heart rate (Δ HR; B), renal blood flow (Δ RBF; C), renal vascular conductance (Δ RVC; D) and renal sympathetic nerve activity (Δ RSNA; E) in sham and A2-lesioned rats. The bars indicate the moment of hypertonic saline infusion. Error bars indicate S.E.M. * p<0.05 compared with baseline; † p<0.05 compared with sham lesion.</p

Baseline values for body weight, MAP, HR, RBF, RVC and RSNA in sham and A2 lesioned rats.

<p>Values are means ± S.E.M. b.wt., body weight; MAP, mean arterial pressure; HR, heart rate; RBF, renal blood flow; RVC, renal vascular conductance; ∫RSNA, integrate of renal sympathetic nerve activity.</p

Effects of A2 noradrenergic neuron lesions on baroreceptor reflexes.

<p>Post-systolic averages of arterial pressure (AP) and renal sympathetic nerve activity (SNA) waves (A) and coherence values between AP and SNA power spectrum (B) before hypertonic saline infusion in sham and A2-lesioned rats.</p

Typical examples.

<p>Digitized record of cardiovascular and sympathetic responses induced by hypertonic saline infusion in sham (A) and A2-lesioned rats (B). ABP = arterial pressure, RBF = renal blood flow, RSNA = renal sympathetic nerve activity (RSNA), hexameth. = hexamethonium.</p