Some drugs exert curative effects intracellu- larly, but their hydrophilic property prohibits the mem- brane-penetrating process and thus limits the curative efficacies, although this property guarantee their solubili...Some drugs exert curative effects intracellu- larly, but their hydrophilic property prohibits the mem- brane-penetrating process and thus limits the curative efficacies, although this property guarantee their solubility in aqueous phase. An example is sodium tanshinone II-A sulfonate （DS-201）, a derivative of Chinese medical herb Danshen （Salvia miltiorrhiza） which is a BKc~ channel opener and a vasodilator. This study established and opti- mized a liposome delivery system which could pack and deliver DS-201 into HEK293 cells transfected with BKca channels, and DS-201 given this way significantly increased the open probability of BKca channel from baseline 0.013 ~ 0.004 to 0.036 -4- 0.011 at -t-40 mV membrane potential （P 〈 0.05） in single-channel attached study, and also increased the current density from baseline 23.2 ＋ 4.4 to 66.0 4- 15.2 pA/pF at ＋40 mV membrane potential （P 〈 0.05）, compared with the direct extracellular administration of this drug. Moreover, showing a ~ 60 % inhibition of the PE or PGF2a induced vascular constric- tion, the DS-201 liposomes did posses significantly enhanced vasorelaxant effect on rat mesenteric artery, compared with 20 % inhibition of the directly administration of this drug （P 〈 0.05）, suggesting that DS-201 delivered by liposomes significantly improved the drug＇s vasorelaxing effect. Taken together, the optimized DS-201 liposomes in our study successfully delivered DS-201 into cells and thus significantly activated BKca channels to reverse the contraction induced by PE and PGF2a, attesting the enhanced bioavailability.展开更多
基金supported by the National Natural Science Foundation of China(3067076381173661+2 种基金31300948)the Sichuan Technology and Education Committee(2011FZ0106and XYTD20100509ZZ010)
文摘Some drugs exert curative effects intracellu- larly, but their hydrophilic property prohibits the mem- brane-penetrating process and thus limits the curative efficacies, although this property guarantee their solubility in aqueous phase. An example is sodium tanshinone II-A sulfonate （DS-201）, a derivative of Chinese medical herb Danshen （Salvia miltiorrhiza） which is a BKc~ channel opener and a vasodilator. This study established and opti- mized a liposome delivery system which could pack and deliver DS-201 into HEK293 cells transfected with BKca channels, and DS-201 given this way significantly increased the open probability of BKca channel from baseline 0.013 ~ 0.004 to 0.036 -4- 0.011 at -t-40 mV membrane potential （P 〈 0.05） in single-channel attached study, and also increased the current density from baseline 23.2 ＋ 4.4 to 66.0 4- 15.2 pA/pF at ＋40 mV membrane potential （P 〈 0.05）, compared with the direct extracellular administration of this drug. Moreover, showing a ~ 60 % inhibition of the PE or PGF2a induced vascular constric- tion, the DS-201 liposomes did posses significantly enhanced vasorelaxant effect on rat mesenteric artery, compared with 20 % inhibition of the directly administration of this drug （P 〈 0.05）, suggesting that DS-201 delivered by liposomes significantly improved the drug＇s vasorelaxing effect. Taken together, the optimized DS-201 liposomes in our study successfully delivered DS-201 into cells and thus significantly activated BKca channels to reverse the contraction induced by PE and PGF2a, attesting the enhanced bioavailability.
