Evaluation of brain-spinal projections in the temporal establishment of renal sympathetic hyperactivation in Renovascular Hypertension

Abstract

The increase of the Sympathetic Nervous Activity (SNA), present in several models of hypertension, can be a determining factor for the genesis and maintenance of the disease. Experimental and clinical studies show that attenuation of elevated SNA may cause an improvement in the prognosis of hypertensive patients, especially those of renovascular origin. Elucidating the mechanisms underlying the increase of SNA in renovascular hypertension may be of great value in understanding the etiology of the disease, and may even contribute to the elaboration of new therapeutic processes. Recent findings obtained in our laboratory point to a change in spinal circuitry in the model 2 kidneys - 1 clip (2K - 1C) of hypertension, especially a modification in glutamatergic and angiotensinergic pathways involved in the establishment of sympathetic pre - ganglionic activity for renal territory. However, the origin of such projections is not yet known. The present project aims to contribute to the knowledge about the role played by the Rostral Ventrolateral Medulla (RVLM) and paraventricular nucleus of the hypothalamus (PVN) on the establishment of high preganglionic activity in the 2k-1C model. In addition, we also intend to evaluate the involvement of such areas for elevated SNA during the course of renovascular hypertension. (AU)