Summary: | Doctoral thesis Mgr. Lenka Hahnová (Cygalová) Placenta, which represents a unique link between the mother and fetus, fulfills many functions essential for normal course of pregnancy and uncomplicated development of the fetus. Nutrient supply, gas exchange and metabolic waste product removal belong to its main roles. In addition, placenta serves as an endocrine, metabolic, immune and protective organ, since during pregnancy mother may be, either unconsciously or deliberately, exposed to a wide range of substances toxic for the fetus. Originally, it was supposed that the physiological barrier between maternal and fetal circulation is created only by cellular layers of syncytiotrophoblast and endothelium of fetal capillaries. However, it has been demonstrated that besides this mechanical component of protection, activity of drug efflux transporters and metabolic enzymes localized in the polarized syncytiotrophoblast layer contribute considerably to the protective function of placental barrier. Efflux transporters are ATP dependent membrane proteins capable of actively removing different molecules out of cells. So far, the best described drug efflux transporters are P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), significantly affecting kinetics of transplacental passage of various...
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