Banca de DEFESA: VERONICA CRISTINA LOPES MENEZES
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.DISCENTE : VERONICA CRISTINA LOPES MENEZES
DATA : 08/05/2020
HORA: 13:50
LOCAL: Instituto de Ciências Biológicas e da Saúde
TÍTULO:
Evaluation of the skin sodium reservoir and hydromineral balance as a function of age and sexual dimorphism in Wistar normotensive and Spontaneously Hypertensive rats (SHR).
PALAVRAS-CHAVES:
hormones, epitelial sodium, hypertension, dimorphism, behaviour.
PÁGINAS: 209
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
SUBÁREA: Fisiologia Geral
RESUMO:
Introduction: The present work was carried out with the support of the Higher Education Personnel Improvement Coordination – Brazil (CAPES) - Finacing code 001. The spontaneously hypertensive animal strain (SHR) is considered as a model of essencial hypertension, being the model that is closer to the hypertension of the human being. This strain up to 4 weeks of age does not present hypertention, which makes it interesting to study phenotipic changes that occur during this animals’ life span. Males and females are diferent in many physiological aspects. The body sodium reserve can be stored in several tissues, being the skin reserve, the interest of this study and in the SHR lineage this aspect has not been elucidated yet. Objectives: To evaluate the physiological status of active and inactive reserves; evaluate changes in the animals’s ingestive pattern making a relationship with blood pressure and sodium reserve; to evaluate diferences between males and females in relation to ingestive behavior; to evaluate changes in hormone concentrations before and after the establishment of hypertention in 4 weeks and 12 weeks old animals. Material and methods: Male and female SHR and Wistar animals, 4 weeks and 12 weeks old, were used. The animals were obtained from the Central Biottery of the Department of Physiological Sciences of UFRRJ. They were kept under standard conditions of light, temperature, and food. Experiments were performed in metabolic cages, radioimmunoassay, tail cuff for pressure assessments and skin sodium and water content analizes. Results: Protocol 1. At the age of 4 weeks SHR males take more sodium from 26 days of age and females from 30 days. Protocol 2: SHR lineage animals had lower weight indexes than Wistar animals. There were no lineage differences in the hormones AVP, OT and ANG II at 4 weeks and 12 weeks of age in females, males SHR and Wistar at 4 weeks of age were no different. Protocol 3: Spontaneously hypertensive animals (SHR) are not hypertensive at 4 weeks of age and become hypertensive at 5 weeks of life. Protocol 4. Accumulated active or inactive reserve does not change with lineage in adult males or offspring, but increases with advancing age in males and females. Discussion: Protocol 1: As expected SHR animals take more hypertonic saline than male or female Wistar animals. Protocol 2: Hormonal differences in AVP are due to physiological variations of gonadal hormones and increased plasma concentration of ANG II in SHR was expected as a trait of the strain. Protocol 3: The increase in the mean arterial pressure was observed in the 5th week of life for the male SHR rats and in the 6th week of life for the female SHR. Protocol 4. In males, hypertension does not make the accumulated sodium reserve different from normotensive animals. Conclusions: Protocol 1: Sodium and water intake are influenced by lineage and sexual dimorphism. Protocol 2: Most hormonal variations occurred due to lineage differences. Protocol 3: The essencial hypertension is related to the age of the animals. Protocol 4. Hypertension does not change osmotically active or inactive reserve under physiological conditions, but age and sexual dimorfism play importante roles.
MEMBROS DA BANCA:
Presidente - 387295 - LUIS CARLOS REIS
Interno - 2225596 - EMERSON LOPES OLIVARES
Interno - 386960 - WELLINGTON DA SILVA CORTES
Externo à Instituição - RENATO RIZO VENTURA - UNIFAL-MG
Externo à Instituição - CLAUDIO DA SILVA ALMEIDA - UES