Medial prefrontal cortical lesions and baroreceptor heart rate reflex sensitivity in the spontaneously hypertensive rat

Abstract

Previous investigations have shown that an excitotoxic lesion of the medial prefrontal cortex (MPFC) in normotensive Sprague-Dawley rats results in a reduction In the sensitivity of the baroreceptor heart rate reflex. The aim of this study was to examine the importance of the MPFC in regulation of the heart rate reflex in conscious, unrestrained spontaneously hypertensive rats (SHR). The MPFC was lesioned by bilateral microinfusions of the excitotoxin Nmethyl-D-aspartlc acid (NMDA). Baroreceptor heart rate reflex testing was performed by measuring reflex heart rate changes in response to blood pressure alterations induced by nitroprusside and phenylephrine with subsequent computerized sigmoi..