[14C]GC Infusion through | Control | OCP | OCP + UDCA |
---|---|---|---|
Umbilical Artery | |||
Placental content at min 2 | |||
nmol | 5.56 ± 0.08 | 2.20 ± 0.09a | 3.02 ± 0.213-b |
Placental content at min 10 | |||
nmol | 1.86 ± 0.12 | 1.38 ± 0.14a | 1.90 ± 0.053-b |
Percentage of uptake | 33.4% | 62.7% | 62.9% |
Cumulative bile output | |||
nmol | 5.37 ± 0.15 | 1.35 ± 0.14a 3-c | 2.87 ± 0.183-b |
Percentage of uptake | 96.6% | 61.4% | 95.0% |
t 1/2 | |||
min | 20.1 ± 1.0 | 56.2 ± 2.8a | 32.6 ± 1.63-b |
Maternal Jugular Vein | |||
Cumulative bile output | |||
nmol | 4.33 ± 0.17 | 3.73 ± 0.15a | 4.53 ± 0.183-b |
t 1/2 | |||
min | 10.7 ± 0.5 | 23.8 ± 1.2a | 24.3 ± 1.3 |
The amount of [14C]GC retained by the placenta after administration (250 nmol over 5 min) through the umbilical artery of in situ perfused rat placentas in 21-day pregnant rats was measured after a 2- or 10-min washing period with [14C]GC-free perfusion medium. In two separate sets of animals, values of [14C]GC bile output into maternal bile over 3 h after administration of [14C]GC through the umbilical artery (250 nmol over 5 min) or through the maternal jugular artery (5 nmol over 5 min) were used to calculate AUC (area under the curve or accumulated output with no extrapolation to infinity) and MRT (mean residence time) by numerical integration using the trapezoidal rule. The half-life time (t1/2) of [14C]GC in the maternal compartment was calculated as Ln2/Ke, where Ke(elimination constant) was 1/MRT (Yamaoka et al., 1978). Groups were control, and rats undergoing surgical common bile duct obstruction on day 14 that, for the remaining 7 days, received the vehicle (OCP group) or 60 μg of UDCA/100 g b.wt./day (OCP + UDCA group). Values are means ± S.E.M. (n ≥ 5).