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Enhanced cardiac sympathetic afferent reflex (CSAR) contributes to sympathetic activation in hypertension.Acute experiments were carried out in 2K1C-induced renovascular hypertensive rats and Sham rats with baroreceptor denervation and vagotomy under anesthesia.CSAR was determined by the responses of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) to epicardial application of capsaicin.Paraventricular nucleus (PVN) microinjection of Ang-(1-7) or cAMP analogue db-cAMP caused greater increases in RSNA and MAP, and enhancement in CSAR in 2K1C rats, while Mas receptor antagonist A-779 produced opposite effects.The effects of Ang-(1-7) were abolished by A-779, adenylyl cyclase inhibitor SQ22536 or PKA inhibitor Rp-cAMP SQ22536 or Rp-cAMP reduced RSNA and MAP in 2K1C rats, and attenuated the CSAR in both Sham and 2K1C rats.Ang-(1-7) in PVN contributes to enhanced RSNA and CSAR in hypertension, which is mediated by Mas receptors and cAMP-PKA pathway.