The Effect of Congenital and Postnatal Hypothyroidism on Depression-Like Behaviors in Juvenile Rats

Abstract

Objective:The aim of this study was to investigate depression-like behaviors of juvenile rats with congenital and postnatal hypothyroidism.Methods:Twenty-seven newborn rat pups were used. First, 6-month-old Wistar Albino female rats were impregnated. Methimazole (0.025% wt/vol) was given to dam rats from the first day of pregnancy until postnatal 21 days (P21) to generate pups with congenital hypothyroidism (n=8), whereas in the postnatal hypothyroidism group (n=10), methimazole was given from P0 to P21. In the control group (n=9), dam rats were fed ad libitum and normal tap water. Offspring were fed with breast milk from their mothers. The behavioral parameters were measured with the juvenile forced swimming test (JFST). The procedure of JFST consisted of two sessions in two consecutive days: the 15-minute pre-test on day 1 and the 5-minute test on day 2.Results:Increased immobility and decreased climbing duration were observed in both congenital and postnatal hypothyroidism groups. Decreased swimming duration was detected in the postnatal hypothyroidism group. Both hypothyroidism groups had a lower body weight gain compared with the control group, while the congenital hypothyroidism group had the lowest body weight.Conclusion:Our results showed that hypothyroidism had negative effects on depression-like behavior as well as on growth and development. Both congenital and postnatal hypothyroidism caused an increase in immobility time in JFST. New studies are required to understand the differing results on depression-like behavior between congenital and postnatal hypothyroidism.

Maternal hypothyroidism in mice influences glucose metabolism in adult offspring

“…While definitive confirmation of hypothyroidism would also require measurement of thyroid-stimulating hormone (TSH), commercial assay kits do not work reliably in mice. Exposure to hypothyroidism in utero has been reported to influence growth in other rodents [28,29]. However, we could not detect significant differences in body mass between mice born to euthyroid or hypothyroid mothers.…”

Methimazole‐induced gestational hypothyroidism affects the offspring development and differently impairs the conditioned fear in male and female adulthood rodents

“…THs play an important role in growth, development, and behavioral processes (Özgür et al, 2016). Here, MMI‐induced gestational hypothyroidism impairs body weight gain in both mother and offspring, especially litter from MMI‐treated group that showed a smallest increase in body weight in PND5 to PND20.…”

Consequências do hipotireoidismo na doença de Chagas experimental

“…Para indução do quadro de hipotireoidismo, os ratos receberam 0,02% de metimazol (MMI) diluídos em água de beber por 21 dias (ÖZGÜR et al, 2016;ZHOU et al, 2015b). O MMI foi obtido da BioLab (BioLab Sanus Pharmaceuticals, São Paulo, Brasil).…”