Department of Physiology, Nanjing Medical University, Nanjing, China.
PLoS One. 2011;6(10):e25784. doi: 10.1371/journal.pone.0025784. Epub 2011 Oct 3.
Cardiac sympathetic afferent reflex (CSAR) contributes to sympathetic activation and angiotensin II (Ang II) in paraventricular nucleus (PVN) augments the CSAR in vagotomized (VT) and baroreceptor denervated (BD) rats with chronic heart failure (CHF). This study was designed to determine whether it is true in intact (INT) rats with CHF and to determine the effects of cardiac and baroreceptor afferents on the CSAR and sympathetic activity in CHF.
METHODOLOGY/PRINCIPAL FINDINGS: Sham-operated (Sham) or coronary ligation-induced CHF rats were respectively subjected to BD+VT, VT, cardiac sympathetic denervation (CSD) or INT. Under anesthesia, renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded, and the CSAR was evaluated by the RSNA and MAP responses to epicardial application of capsaicin. Either CSAR or the responses of RSNA, MAP and CSAR to Ang II in PVN were enhanced in CHF rats treated with BD+VT, VT or INT. Treatment with VT or BD+VT potentiated the CSAR and the CSAR responses to Ang II in both Sham and CHF rats. Treatment with CSD reversed the capsaicin-induced RSNA and MAP changes and the CSAR responses to Ang II in both Sham and CHF rats, and reduced the RSNA and MAP responses to Ang II only in CHF rats.
The CSAR and the CSAR responses to Ang II in PVN are enhanced in intact CHF rats. Baroreceptor and vagal afferent activities inhibit CSAR and the CSAR responses to Ang II in intact Sham and CHF rats.
心脏交感传入反射（CSAR）有助于交感神经激活，血管紧张素 II（Ang II）在室旁核（PVN）中增强迷走神经切断（VT）和压力感受器去神经（BD）的慢性心力衰竭（CHF）大鼠中的 CSAR。本研究旨在确定在完整（INT）CHF 大鼠中是否如此，并确定心脏和压力感受器传入对 CSAR 和 CHF 中交感神经活动的影响。
方法/主要发现：分别对假手术（Sham）或冠状动脉结扎诱导的 CHF 大鼠进行 BD+VT、VT、心脏交感神经切断（CSD）或 INT。在麻醉下，记录肾交感神经活动（RSNA）和平均动脉压（MAP），并通过心外膜应用辣椒素评估 RSNA 和 MAP 对 CSAR 的反应。在接受 BD+VT、VT 或 INT 治疗的 CHF 大鼠中，CSAR 或 RSNA、MAP 和 CSAR 对 PVN 中 Ang II 的反应增强。VT 或 BD+VT 处理增强了 Sham 和 CHF 大鼠的 CSAR 和 CSAR 对 Ang II 的反应。CSD 处理逆转了 Sham 和 CHF 大鼠中辣椒素诱导的 RSNA 和 MAP 变化以及对 Ang II 的 CSAR 反应，并仅降低了 CHF 大鼠对 Ang II 的 RSNA 和 MAP 反应。
在完整的 CHF 大鼠中，CSAR 和 PVN 中 Ang II 对 CSAR 的反应增强。压力感受器和迷走神经传入活动抑制完整 Sham 和 CHF 大鼠中的 CSAR 和 Ang II 对 CSAR 的反应。
