CAJ | 학술논문

目的探讨大电导钙激活钾(BKCa)通道在阻塞性黄疸大鼠血管低反应性中的作用.方法雄性SD大鼠18只,体重180 ～ 200 g,采用随机数字表法分为3组:(n=6):空白对照组(C组)、假手术组(S组)和胆管结扎组(BDL组).采用胆道结扎法制备阻塞性黄疸模型.术后7d时,取血样,测定血清总胆红素(TBL)、直接胆红素(DBL)、间接胆红素(IBL)、丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)的水平.制备胸主动脉环,去掉血管内皮,分别灌注梯度浓度的去甲肾上腺素和硝普钠,记录动脉环最大收缩与舒张幅度,随后灌注BKCa通道阻断剂(Chtx),终浓度为10-7 mol/L,再分别灌注梯度浓度的去甲肾上腺素和硝普钠,记录各浓度下动脉环最大收缩与舒张幅度.计算动脉环最大收缩和舒张百分比(Chtx给药后最大幅度÷给药前最大幅度×100％).结果与C组和S组比较,BDL组大鼠血清TBL、DBL、IBL、ALT和AST水平升高,动脉环对去甲肾上腺素诱发的最大收缩幅度降低,最大收缩百分比升高,对硝普钠诱发的最大舒张幅度升高,最大舒张百分比降低(P＜0.05).结论 BKCa通道过度开放可能参与了阻塞性黄疸大鼠血管低反应性的发生机制.
목적 탐토대전도개격활갑(BKCa)통도재조새성황달대서혈관저반응성중적작용.방법 웅성SD대서18지,체중180 ～ 200 g,채용수궤수자표법분위3조:(n=6):공백대조조(C조)、가수술조(S조)화담관결찰조(BDL조).채용담도결찰법제비조새성황달모형.술후7d시,취혈양,측정혈청총담홍소(TBL)、직접담홍소(DBL)、간접담홍소(IBL)、병안산전안매(ALT)화천동안산전안매(AST)적수평.제비흉주동맥배,거도혈관내피,분별관주제도농도적거갑신상선소화초보납,기록동맥배최대수축여서장폭도,수후관주BKCa통도조단제(Chtx),종농도위10-7 mol/L,재분별관주제도농도적거갑신상선소화초보납,기록각농도하동맥배최대수축여서장폭도.계산동맥배최대수축화서장백분비(Chtx급약후최대폭도÷급약전최대폭도×100％).결과 여C조화S조비교,BDL조대서혈청TBL、DBL、IBL、ALT화AST수평승고,동맥배대거갑신상선소유발적최대수축폭도강저,최대수축백분비승고,대초보납유발적최대서장폭도승고,최대서장백분비강저(P＜0.05).결론 BKCa통도과도개방가능삼여료조새성황달대서혈관저반응성적발생궤제.
Objective To evaluate the role of large conductance calcium-activated potassium (BKCa) channels in vascular hyporesponsiveness in rats with obstructive jaundice.Methods Eighteen male Sprague-Dawley rats,weighing 180-200 g,were randomly divided into 3 groups (n =6 each) using a random number table:control group (group C),sham operation group (group S),and bile duct ligation group (group BDL).Obstructive jaundice was produced by common bile duct ligation.At 7 days after surgery,blood samples were collected for determination of the levels of serum total bilirubin (TBL),direct bilirubin (DBL),indirect bilirubin (IBL),alanine aminotransferase (ALT),and aspartate aminotransferase (AST).Thoracic aortic rings were prepared,and the endothelium was removed.The aortic rings were sequentially perfused with different concentrations of norepinephrine (NE) and sodium nitroprusside (SNP),and the maximum amplitude of contraction and dilatation of aortic rings was recorded.The aortic rings were then perfused with BKCa channel blocker Chtx with the final concentration of 10 7 mol/L,followed by perfusion with different concentrations of NE and SNP again,and the maximum amplitude of contraction and dilatation of aortic rings was recorded under each concentration.The percentage of maximum contraction and dilatation (maximum amplitude after Chtx administration÷maximum amplitude before Chtx administration× 100％) was calculated.Results Compared with C and S groups,the levels of TBL,DBL,IBL,ALT and AST in serum were significantly increased,the maximum amplitude of NE-induced contraction of aortic rings was decreased,and the percentage of the maximum NE-induced dilatation of aortic rings was increased,the maximum amplitude of SNP-induced contraction of aortic rings was increased,and the percentage of the maximum SNP-induced dilatation of aortic rings was decreased in group BDL.Conclusion Excessivc opening of BKCa channels may be involved in the mechanism of vascular hyporesponsiveness in rats with obstructive jaundice.