Immunohistochemical evaluation of the effects of maternal hypothyroidism during pregnancy and lactation on the expression of laminin in the lung alveoli of newborn Wistar rats

In this study، we have used immunohistochemical studies to examine the effects of maternal hypothyroidism on the expression of laminin in the lung alveoli newborn Wistar rats examined. in this study we have used female virgin rat، wistar strain. Rats were divided in two experimental groups (hypothyroid and hyperthyroid treated with thyroxin) and one control group (n=12). 14 days before mating in the experimental groups، the rats respectively were exposed to Propylthiouracil (50 mg/L) as well as thyroxin (1 mg/L) and Propylthiouracil (50 mg/L) simultaneously. After 14 days، blood test was taken from mothers and in case of desired changes in hormone levels، rats were allowed to mate. After delivery، the lung of the 10 days old newborns were used for immunohistochemical studies. There was a significant reduction in laminin expression in hypothyroid group (p= 0. 001) where as no significant difference was observed in hypothyroid group treated with thyroxin compared to control group. Thyroid hormones have important role on laminin expression and development of lung، since maternal hypothyroidism causes large reduction in alveiolar laminin expression. Therefore changes in maternal thyroid hormone can cause large changes in alveolar development in newborns.