Objective: Maturation of heart is characterized by increase of Creatine Kinase. We have reported that cardiac-function related proteins increased with prenatal glucocorticoid administration in the fetal rat models. The aim of the present study was to demonstrate the effect of prenatal glucocorticoid administration on the creatine kinase level in fetal and neonatal cardiac tissues.
Methods: Dexamethasone(DEX) was administrated to pregnant rat for 2 days on day 19 and 20 of gestation to simulate preternal DEX theraphy. Mitochondria was extracted from the fetal and neonatal cardiac tissues, then the expression of creatine kinase in mitochondria was analyzed using western blotting and immunohistochemistry. Uptake of
JC-1 (5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethyl-benzimidazolocarbocyanine iodide) to mitochondria was measured using fluorometry, as a parameter of its function.
Results: Expression of creatine kinase in 21-day fetus and 1-day neonates of DEX groups were significantly increased compared to the control. The uptake of JC-1 to mitochondria was also significantly increased in fetal and neonatal DEX group.
Conclusions: These results will suggest that perinatal glucocorticoid administration increases cardiac contraction-related proteins and may contribute to the maturation of the cardiac tissue and also to the mitochondrial activation in the fetal rats.