Neural mechanisms involved in the generation of arterial hypertension in female rats submitted to chronic intermittent hypoxia

• Grant number: 15/06550-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2015
• End date: May 31, 2017
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Benedito Honorio Machado
• Grantee: George Miguel Perbone Robuste Souza
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 13/06077-5 - Changes in the neural networks involved with the generation and control of sympathetic and respiratory activities in different experimental models of hypoxia, AP.TEM

Abstract

Chronic intermittent hypoxia (CIH) promotes changes in the respiratory- sympathetic coupling and hypertension in male rats. After CIH, male rats present increased sympathetic activity during the late phase of expiration, which may contribute, at least in part, to the development of hypertension. Similarly, recent studies from our laboratory have shown that female rats submitted to CIH develop high blood pressure and changes in the respiratory-sympathetic coupling, different from the pattern observed in males, since CIH-female rats have increased sympathetic activity during inspiration. These observations suggest that although both male and female rats develop hypertension after CIH, the neural mechanisms underlying the changes in sympathetic respiratory coupling are different. Considering this information, the hypothesis of the present project is: female rats submitted to CIH have increased sympathetic activity related to inspiration, suggesting that pre-sympathetic and respiratory neurons present changes in their activity, becoming more excitable after CIH. To test this hypothesis, we will study the activity of pre-sympathetic and respiratory neurons in the ventral medulla of juvenile female rats submitted to CIH. For this, we will use the working heart brainstem preparation. With this study we can achieve important electrophysiological information for a better understanding about the respiratory modulation of neurons involved in the generation of sympathetic activity and its implications in the pathogenesis of hypertension in females. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SOUZA, GEORGE MIGUEL P. R.; AMORIM, MATEUS R.; MORAES, DAVI J. A.; MACHADO, BENEDITO H.. Sex differences in the respiratory-sympathetic coupling in rats exposed to chronic intermittent hypoxia. Respiratory Physiology & Neurobiology, v. 256, n. SI, p. 109-118, OCT 2018. (13/06077-5, 15/06550-8)

SOUZA, GEORGE M. P. R.; BARNETT, WILLIAM H.; AMORIM, MATEUS R.; LIMA-SILVEIRA, LUDMILA; MORAES, DAVI J. A.; MOLKOV, I, YAROSLAV; MACHADO, BENEDITO H.. Pre- and post-inspiratory neurons change their firing properties in female rats exposed to chronic intermittent hypoxia. Neuroscience, v. 406, p. 467-486, MAY 15 2019. (13/06077-5, 15/06550-8)

SOUZA, GEORGE MIGUEL P. R.; AMORIM, MATEUS R.; MORAES, DAVI J. A.; MACHADO, BENEDITO H.. Sex differences in the respiratory-sympathetic coupling in rats exposed to chronic intermittent hypoxia. Respiratory Physiology & Neurobiology, v. 256, p. 10-pg., 2018-10-01. (15/06550-8, 13/06077-5)