Would the previous treatment with paroxetine improve baroreflex activity in rats that will suffer a cardiac volume overload?

• Grant number: 11/20131-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2011
• End date: November 30, 2012
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Juliana Irani Fratucci de Gobbi
• Grantee: Renato Villarino Pinto
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Aortic regurgitation (AR) develops one of the largest responses of myocardial hypertrophy observed in the heart diseases. In Brazil, the valvar heart disease is still prevalente, being the main cause of the AR the rheumatic fever. Usually, the patient with AR stays asymptomatic for a long period until that in the chronic phase of the disease, already with systolic dysfunction, the patient looks for the medical treatment. Acute AR, although less frequent than the chronicle, presents bad prognostic. Rats with acute AR present increased water intake and natriuresis after the combined treatment of furosemide associated to the low dose of the inhibitor of the converting enzyme of angiotensin II, the captopril. A very common comorbidity associated to cardiovascular diseases it is depression. Among the antidepressants more prescribed all over the world are the selective inhibitors of serotonin reuptake (SISR). An important serotonergic pathway between pons and midbrain contributes to inhibit the ingestion of sodium and water. Preliminary studies of our laboratory showed that the treatment with paroxetine, an SISR, preserved the shortening fraction in mice with subchronic AR and it reduced the daily ingestion of sodium. A hypothesis to be tested is whether the previous treatment with paroxetine could preserve the progression of a heart offense, the AR, in rats. Therefore, the objectives of the present project are to verify the effect of the previous treatment with paroxetine in rats that will suffer acute AR on: a) the blood pressure and heart frequency answers to the baroreflex front of the depressive dose of sodium nitroprusside and pressor dose of phenylephrine, and c) the morphofunctional variables of the heart.(AU)