The effect of pregnancy and treatment with 17 beta-estradiol on the transport of organic anions into isolated rat hepatocytes.

The uptake of the bile acid taurocholate (TC), and the organic anions, estradiol-17 beta (beta-D-glucuronide) (E217G), estradiol-3-(beta-D-glucuronide) (E23G), estriol-16 alpha (beta-D-glucuronide) (E316G), and morphine glucuronide (MG) were evaluated in hepatocytes isolated from nonpregnant female, pregnant (19-21 days of gestation) and E2-treated (1 mg/kg/day sc for 14 days) rats. Pregnancy significantly decreased the uptake of TC, E217G, E23G, and MG whereas E2 treatment decreased only the uptake of E217G. The Vmax (nmol/min/mg protein) for E217G uptake was significantly decreased from 1.45 +/- 0.2 (mean +/- SE) in hepatocytes from nonpregnant female rats to 0.70 +/- 0.11 and 0.64 +/- 0.13 in cells from pregnant and E2-treated rats, respectively. The Vmax for uptake of TC was decreased, but not significantly, from 0.56 +/- 0.16 in hepatocytes from nonpregnant female rats to 0.34 +/- 0.08 in cells from pregnant rats.