Influencia de la hipertensión sobre el contenido de catecolaminas del complejo vagal dorsal de la rata

Abstract

The dorsal vagal complex (CVD) is formed by the nucleus tractus solitarii, (NTS), the dorsal motor nucleus of the vagus nerve (NMDV) and the area postrema (AP).The CVD functions has been connected with the cardiovascular regulations and is considered a relay centre for integrating central and peripheral signals related to cardiovascular regulation. The NTS is the primary site for cardiovascular afferent fibres termination and which are innervated by catecholaminergic neurons. The present work quest more evidences on the implication of the CVD catecholaminergic neurons in the development of and arterial hypertension. Control WKY and hypertensive SHR rats were used. Antibodies to the catecholamine synthetic enzymes tyrosine-hydroxylase (TH) and dopamine-beta-hydroxylase (DBH) were used in the immunohistochemical and western blot analysis. The TH and DBH material immunoreactive were located throughout the rostrocaudal and dorsoventral extent of the area postrema, as well as in neurons within the NTS. The distribution and the number of TH neurons were the similar as those DBH, except in the dorsal motor nucleus of the vagus. In the area postrema the number of neurons immunocytochemical labelled for TH was higher than those labelled for DBH. The hypertension produced an increase of the IRM for both of two antibodies TH and DBH in the three nuclei that form the CVD. Thereafter, we could conclude that in the SHR rat is produced an activation of the catecholaminergic central system expressed by an increase of the catecholamines in the dorsal vagal complex.