A method to assess heart rate variability in neonate rats: validation in normotensive and hypertensive animals

Autor(es)

S.C.F. Freitas ^[1] ; C. Paixão dos Santos ^[2] ; A. Arnold ^[3] ; F.F. Stoyell-Conti ; M.R.H. Dutra ^[5] ; M. Veras ^[6] ; M.C. Irigoyen ^[7] ; K. De Angelis

Afiliação do(s) autor(es)

^[1] Laboratório de Fisiologia Translacional, Universidade Nove de Julho - Brasil

^[2] Departamento de Fisiologia, Universidade Federal de São Paulo - Brasil

^[3] Instituto do Coração, Faculdade de Medicina de São Paulo. Unidade de Hipertensão - Brasil

^[5] Laboratório de Fisiologia Translacional, Universidade Nove de Julho - Brasil

^[6] Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo - Brasil

^[7] Instituto do Coração, Faculdade de Medicina de São Paulo. Unidade de Hipertensão - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 53, n. 8 2020-06-26.

Resumo

Several studies have focused on the heart rate variability (HRV) of murine species, while studies discussing HRV in murine neonates and infants remain scarce, since recording hemodynamic signals through invasive methods in small animals has been found to be quite challenging. Thus, this study aimed at describing and validating a novel method to assess HRV in newborn rats. An electrocardiogram (ECG) system was used to determine RR intervals in awake newborns and evaluate HRV in normotensive (Wistar) and hypertensive (SHR) neonate rats. After birth, ECG was recorded in the awake newborns, and they were allowed to rest on a heated surface, restricted only by the weight of the adhesive ECG electrodes. The electrodes were cut and adapted to provide more comfort to the animal, and gently placed on the newborn's skin. RR intervals were recorded over a 30-min period using an ECG system together with LabChart software (4 KHz). Three sequences of 5 min each from the ECG recording period were analyzed in time and frequency domains, using CardioSeries software. ECG data resulted in a clearly interpretable signal that was used to generate an RR interval sequence through time for the analysis of HRV. SHR neonates presented increased cardiac sympathovagal balance compared to Wistar neonates (low frequency/high frequency: 3.85±0.71 vs 0.90±0.09). In conclusion, the ECG setup here described may be used to record RR intervals to assess HRV in neonate rats, thus detecting early impairment of HRV in hypertensive newborns. (AU)

• Processo FAPESP: 18/19006-2 - Associação entre biomarcadores séricos, funcionais e exames de imagem na disfunção diastólica e cognitiva
• Beneficiário: Maria Claudia Costa Irigoyen
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/17183-4 - Sobrecarga de frutose em genitores: impacto do treinamento físico nas alterações cardiometabólicas e neuroimunes da prole
• Beneficiário: Kátia de Angelis Lobo D Avila
• Modalidade de apoio: Auxílio à Pesquisa - Regular