Pro-inflammatory cytokines in the paraventricular nucleus mediate the adipose afferent reflex in rats.

This study determined whether PICs in the PVN mediate the AAR in rats. The AAR was evaluated based on renal sympathetic nerve activity and mean arterial blood pressure in response to capsaicin injection into inguinal WAT (iWAT). PIC levels were measured by ELISA. PVN microinjection with the PICs tumor necrosis factor (TNF)-α or interleukin (IL)-1β enhanced the AAR in a dose-dependent manner. Furthermore, pretreatment via the bilateral microinjection of the TNF-α-blocker etanercept or IL-1β blocker IL-1ra into the PVN attenuated the AAR. In rats pretreated with TNF-α or IL-1β, a sub-response dose of angiotensin II (Ang II) significantly enhanced the AAR. Moreover, delivery of the angiotensin II type 1(AT1) receptor antagonist losartan into the PVN attenuated the effects of TNF-α or IL-1β on the AAR. In addition, stimulating either iWAT or retroperitoneal WAT with capsaicin increased TNF-α or IL-1β levels in the PVN, but the injection of capsaicin into the jugular vein, skeletal muscle, and skin had no effects on TNF-α or IL-1β levels in the PVN. These results suggest that TNF-α or IL-1β and Ang II in the PVN synergistically enhance the AAR in rats. PMID: 32086614 [PubMed - as supplied by publisher]
Source: Pflugers Archiv : European Journal of Physiology - Category: Physiology Authors: Tags: Pflugers Arch Source Type: research