P-glycoprotein (P-gp) is a membranous ATPase responsible for the multidrug resistance (MDR) phenotype. Using membrane vesicles prepared from the highly resistant cell line DC-3F/ADX we studied the influence of P-gp ATPase activity of four progesterone derivatives which specifically bind to P-gp and reverse MDR. Progesterone and desoxycorticosterone stimulate P-gp ATPase activity with, respectiv...

A role for glycoprotein (GP)V in platelet function has been proposed on the basis of observations that GP V is the major thrombin substrate on intact platelets cleaved during thrombin-induced platelet aggregation, and that GP V promotes GP Ib-IX surface expression in heterologous cells. We tested the hypotheses that GP V is involved in thrombin-induced platelet activation, in GP Ib-IX expressio...

background: the development of injectable sustained-release products are of great interest to veterinary pharmaceuticals and animal health business. recently, great attention has been paid to in situ gel-forming chitosan/beta-glycerophosphate (chitosan/β-gp) solutions due to their good biodegradability and thermosensitivity. objectives: the general aim of this study was to prepare a novel in si...

P-glycoprotein (P-gp) and cytochrome P450 3A4 (CYP3A4) play a significant role in the disposition and elimination of drugs. The objective of this study was to investigate the mechanism underlying the interaction between sitagliptin (substrate of P-gp and CYP3A4) and verapamil (known modulator of P-gp and CYP3A4) using in vivo, ex vivo and in situ models. Rats were treated with sitagliptin (10 m...

Drug resistance is a major cause of chemotherapy failure in cancer treatment. One reason is the overexpression of the drug efflux pump P-glycoprotein (P-gp), involved in multidrug resistance (MDR). In vivo pharmacokinetic analysis of P-gp transport might identify the capacity of modulation by P-gp substrate modulators, such as cyclosporin A. Therefore, P-gp function was measured in vivo with po...