Pharmacokinetics of placental protein 13 after intravenous and subcutaneous administration in rabbits

Introduction: Human placental protein 13 (PP13) is a galectin predominantly expressed by the placenta. Low serum concentrations of PP13 in early pregnancy indicate a higher risk of developing preeclampsia. Methods: The pharmacokinetic disposition and bioavailability of PP13 were determined by single intravenous and subcutaneous administration to 12 healthy New Zealand White rabbits. The serum pharmacokinetic values were determined by enzyme-linked immunosorbent assay, and are best described by a two-compartment model. Results: Both volume of distribution and the area under the curve were dose dependent for the intravenous group (p < 0.01). PP13 elimination half-life was also found to be different between the groups (p < 0.01). The bioavailability of PP13 following subcutaneous administration was found to be 57%. Conclusion: This study shows that the concentration of total PP13 released into the maternal circulation during pregnancy might be much higher than previously estimated.