Effects of Antenatal Dexamethasone on Cerebral Intra and Extra-cellular Calcium Concentrations in Asphyxiated Rat Fetuses / 中华围产医学杂志

ABSTRACT

Objective To investigate whether antenatal administration of dexamethasone would provide protection against cerebral hypoxic ischemic damage in asphyxiated fetal rats. Methods Fifty seven fetal rats of twenty day gestational age were randomly divided into five groups sham operation (normal control, n =11), asphyxiated control (group E, n =10), and group D 1?D 2?D 3 of different timings of intravenous dexamethasone treatment (1 mg/kg) in pregnant SD rats ( n =15, 12, and 9 respectively). The times assigned for dexamethasone injection were thirty minutes before clamping, the time aroung clamping and the beginning of reperfusion respectively. Intra and extra cellular concentrations of calcium, sodium and potassium in fetal rat brains were measured in each group after thirty minutes of reperfusion. Results (1)Intracellular free calcium concentrations of fetal rat brains in group E,D 1, D 2 and D 3 were 552?94, 438?105, 445?57, and 456?110 nmol/L respectively, and all significantly higher than that in the normal control 315?87 nmol/L ( P