Acute exposure to doxorubicin results in increased cardiac P-glycoprotein expression.

Doxorubicin is a frequently used anticancer drug, but its use is restricted due to the occurrence of severe side effects, namely strong cardiotoxicity. It is known from cancer cells that doxorubicin enhanced the expression of its efflux pump P-glycoprotein (P-gp), which may modulate local drug concentrations. We therefore studied the cardiac expression of P-gp in doxorubicin-treated mice.

Uptake of cardiovascular drugs into the human heart: expression, regulation, and function of the carnitine transporter OCTN2 (SLC22A5).

Background: To date, the uptake of drugs into the human heart by transport proteins is poorly understood. A candidate protein is the organic cation transporter novel type 2 (OCTN2) (SLC22A5), physiologically acting as a sodium-dependent transport protein for carnitine. We investigated expression and localization of OCTN2 in the human heart, uptake of drugs by OCTN2, and functional coupling of OCTN2 with the eliminating ATP-binding cassette (ABC) transporter ABCB1 (P-glycoprotein).