title: Experimental gestational hypothyroidism evokes hypertension in adult offspring rats.
abstract: Gestational hypothyroidism is a prevalent disorder in pregnant women. We aimed to investigate the impact of experimental gestational hypothyroidism (EGH) on cardiovascular and autonomic nervous systems (ANS) in the offspring of rats. EGH was induced with methimazole (MMI) 0.02% in drinking water from day 9 of gestation until birth. Sixty day old offspring from MMI-treated dams (OMTD, n=13) or water-treated dams (OWTD, n=13) had femoral arteries surgically assessed for the measurements of heart rate (HR), mean (MAP), systolic (SAP) and diastolic arterial pressure (DAP), and spontaneous baroreflex sensitivity (BRS). To investigate the balance of ANS, we established the high (HF) and low frequency (LF) bands of pulse interval (PI) and LF band of SAP spectrum. OMTD had increased MAP (130.2 ± 2.0 vs 108.8 ± 3.0 mmHg, p<0.001), SAP (157.3 ± 2.9 vs 135.7 ± 4.5mm Hg, p<0.001) and DAP (109.7 ± 1.9 vs 88.4 ± 2.6 mmHg, p<0.001) when compared to OWTD, and had lower HR (355.1 ± 8.9 vs 386.8 ± 9.2 bpm, p<0.05). After spectral analysis of PI and SAP, only LF band of SAP spectrum was higher (7.2 ± 0.8 vs 4.0 ± 0.6 mmHg(2), p<0.01) in OMTD under spontaneous condition. Despite bradycardia, EGH promotes spontaneous hypertension in 60 day old offspring, probably due to increased sympathetic modulation of vessels, which is suggested by the higher LF of SAP. These findings suggest a critical role of maternal THs in the development of fetal cardiovascular and autonomic nervous systems.
authors.affiliation: Departamento de Fisiologia, Universidade Federal de Sergipe, Aracaju, SE, Brazil.
authors.forename: Sheyla Oliveira
authors.initials: SO
authors.lastname: Santos
authors.forename: Saulo Makerran Araújo
authors.initials: SM
authors.lastname: Loureiro
authors.forename: Iura Gonzalez Nogueira
authors.initials: IG
authors.lastname: Alves
authors.forename: Camila Santos de
authors.initials: CS
authors.lastname: Jesus
authors.forename: Patrícia Rabelo dos
authors.initials: PR
authors.lastname: Santos
authors.forename: Márcio Roberto Viana dos
authors.initials: MR
authors.lastname: Santos
authors.forename: Daniel Penteado Martins
authors.initials: DP
authors.lastname: Dias
authors.forename: Valter Joviniano
authors.initials: VJ
authors.lastname: Santana-Filho
authors.forename: Daniel
authors.initials: D
authors.lastname: Badauê-Passos
mesh_terms: D000818:Animals; D017704:Baroreflex / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D004195:Disease Models, Animal; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006973:Hypertension / Q000150:complications / Q000503:physiopathology*; D007037:Hypothyroidism / Q000139:chemically induced / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008713:Methimazole; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000503:physiopathology*; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D008713:Methimazole