EFFECTS OF PHYSIOLOGICAL DEPRIVATION OF OVARIAN HORMONES ON CARDIAC MORPHOLOGY AND FUNCTIONALITY IN SPONTANEOUSLY HYPERTENSIVE RATS - ROLE OF AGING

• Grant number: 23/13473-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2024
• End date: December 31, 2024
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Hugo Celso Dutra de Souza
• Grantee: Mariana Romanato Rodrigues
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Introduction: Systemic arterial hypertension (SAH) is accompanied by pathological left ventricular hypertrophy and alterations in cardiac functionality. However, in women of reproductive age, this condition may be less severe due to the cardiovascular protection exerted by ovarian hormones. In this context, physiological ovarian failure (menopause) would represent a watershed in this protection, which may favor the development of more severe morphological and functional cardiac alterations. However, it is necessary to separate the effects inherent to the aging process. Objective: To investigate whether physiological ovarian failure in spontaneously hypertensive rats (SHR) results in more severe morphological and functional impairments when compared to normotensive female rats (WK), or whether aging is a condition that prevails over morphological and functional impairments. Methods: 32 animals (40 weeks old) will be divided into two large groups; group of Wistar Kyoto rats (WK; N=16) and group of spontaneously hypertensive rats (SHR; N=16). Half of each group will undergo ovarian hormone deprivation through ovariectomy (N=8) or SHAM surgery (N=8) at the 60th week of life. All animals will be evaluated using the following protocols: recording of blood pressure and heart rate through plethysmography to be performed on the 40th, 48th, 56th, 64th and 72nd weeks of life and cardiac morphofunctional assessment through two-dimensional echocardiography on the 40th, 60th and 72nd weeks.