Objective:To study protein expression of ATP-sensitive potassium channels(KATP) of pulmonary artery in chronic hypoxic pulmonary artery hypertension(CHPAH) rats and in chronic hypoxic rats treated with KATP opener Pinacidil and Diazoxide. Methods:Thirty-five Sprague-Dawley(SD) male rats were randomly divided into five equal groups:control group,hypoxic group,Pinacidil group[2.0 mg/(kg·d),ig],Diazoxide group[1.5 mg/(kg·d),ig] and 5-HD+Diazoxide group[5-HD 3.0 mg/(kg·d),ig,Diazoxide 1.5 mg/(kg·d),ig]. Except the first group ,the other four groups were put into hypoxic and normobaric chamber[O2(10.0 ± 0.5)%] to establish chronic hypoxic model. Four weeks later,the mean pulmonary arterial pressure(mPAP) was measured. Western-blot was performed to analyze the protein level of KATP channels in pulmonary main artery smooth muscles. Results:①The level of mPAP was significantly higher in the hypoxic group than those in control group(P < 0.05). Pinacidil 2.0 mg/(kg·d) decreased the level of mPAP(mmHg) significantly. While Diazoxide 1.5 mg/(kg·d) increased the level of mPAP significantly. The level of mPAP was significantly lower in the 5-HD+Diazoxide group than those in Diazoxide 1.5 mg/(kg·d) group. ②The protein levels of SUR2B in the hypoxic group were significantly lower than those in the control group,and this decrease was partly reversed by Pinacidil. The protein levels of SUR2B in the Diazoxide group were significantly lower than those in the hypoxic group. The protein levels of SUR2B in the 5-HD+Diazoxide group were significantly higher than those in the Diazoxide group,and no difference in Kir 6.1 protein level was found among five groups. Conclusion:KATP channel protein expression was inhibited by chronic hypoxia,and this inhibition could be up-regulated by Pinacidil. Pinacidil might partly prevent the development of HPH and the pulmonary vascular remodeling;Diazoxide could aggravate the level of mPAP and down-regulate the protein expression of KATP channel.
陈〓磊,解卫平,金〓宇,王 虹.吡那地尔及二氮嗪对长期低氧大鼠肺动脉平滑肌KATP通道蛋白表达的影响[J].南京医科大学学报(自然科学版英文版),2008,28(3):308-311315.