Studies on the Metabolic Fate of Carvedilol (V) Transfer into the Fetuses in Rats.

Abstract

The transport of carvedilol to fetuses via placenta was studied in pregnant rats on days 12 and 19 of gestation after a single oral administration of ¹⁴C-carvedilol at a dose of 10mg/kg.
1. On day 12 of gestation, the concentrations of radioactivity in the fetus were lower than that in the maternal blood as determined by liquid scintillation counting and autoradiography. The percentage distribution of radioactivity in a fetus amounted to less than 0.01% of dose.
2. On day 19 of gestation, the concentrations of radioactivity in fetal plasma, fetal blood and fetal liver at 1 hr were nearly half as high as that in the maternal plasma. The percentage distribution of radioactivity in a fetus amounted to 0.01% of dose.
Biliary excretion in fetus was suggested from the observation of relatively high concentration of radioactivity in fetal intestine at 24hr. It was concluded that the transfer of carvedilol into fetus was low.