Simultaneous Measurement of Hypothalamic Paraventricular Nucleus Neuronal and Sympathetic Nerve Activity in Freely Moving Rats

Abstract

The hypothalamic paraventricular nucleus (PVN) plays important role in regulation of sympathetic nerve activity (SNA). Studies have reported that the PVN projects directly to the sympathetic preganglionic neurons of the spinal cord and pre‐sympathetic motor neurons of the rostral ventrolateral medulla. However, to our knowledge, simultaneous measurement of PVN neuronal activity (PVNNA) and SNA in freely moving animals has not been reported. Thus, the functional relationship between PVNNA and SNA remains unclear. The aim of the present study was to establish a method for simultaneous and continuous measurement of PVNNA and SNA in freely moving rats. Male Wistar rats were chronically instrumented with multiple electrodes (100‐μm stainless steel wire) for measurement of PVNNA, renal SNA (RSNA), electroencephalogram, electromyogram, and electrocardiogram, and with a catheter for measurement of arterial pressure (AP). PVNNA and RSNA were measured continuously in rats during daily activity and in response to air jet stress. We found that PVNNA changed in a behavioral‐dependent manner. Rapid eye movement sleep increased PVNNA, LSNA, and mean AP, but decreased RSNA and heart rate. In addition, PVN, RSNA, mean AP, and heart rate increased in response to air jet stress. These data suggest that the functional relationship between PVNNA, RSNA, and LSNA is altered depending on changes in physiological conditions.Support or Funding InformationJSPS GrantThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.