Beschreibung:
<jats:p>We recently reported that sympathetic nerve activity (SNA) to the kidneys and hindlimb do not contribute to AngII‐salt hypertension (HTN) despite elevated whole body sympathetic tone. We tested the hypothesis that AngII‐salt HTN is associated with enhanced sympathetic tone to the heart and splanchnic vascular bed. Mean arterial pressure (MAP), heart rate (HR) and superior mesenteric artery blood flow (SMABF) were measured in rats fed a high (2%) NaCl diet during 4 days of control and 14 days of AngII infusion (150ng/kg/min, sc). Changes in sympathetic tone on MAP, HR, and mesenteric vascular resistance (MVR; SMABF/MAP) were assessed during control, and days 3, 7, and 13 of AngII by ganglionic blockade (hexamethonium; 20mg/kg, iv). MAP (140±4 mmHg) and depressor response to hexamethonium (−86±5) on Day 13 of AngII was significantly elevated compared to control (97±1 and −41±1, respectively). HR and MVR were 402±7 BPM and 9.7±0.8 mmHg·min/mL during control. By day 13 of AngII, HR was 397±5 and MVR was 14±1. The change in HR after ganglionic blockade was −37±10 during control, +20±24 on Day 3, −50±10 on Day 7 and −60±10 on Day 13 of AngII. The decrease in MVR after ganglionic blockade was similar during control (−2.6±0.3) and Day 3 (−3±1), but enhanced on Day 7 (−7±1) and Day 13 (−5.8±0.9) of AngII. We conclude that increased sympathetic tone on MAP in AngII‐sat HTN is associated with enhanced sympathetic tone on HR and MVR (<jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="DDBJ/EMBL/GenBank" xlink:href="HL076312">HL076312</jats:ext-link>).</jats:p>