{"title":"雌二醇对豚鼠心室肌细胞内向整流和延迟整流K+电流的抑制作用。","authors":"Y Zhang, L L Song, S Z Gu, S G Lu, Z N Zhou","doi":"","DOIUrl":null,"url":null,"abstract":"<p><strong>Aim: </strong>To study the effects of estradiol (Est) on inward rectifier K+ (IK1) and delayed rectifier K+ (IK) channels in isolated guinea pig ventricular myocytes.</p><p><strong>Methods: </strong>Using whole cell patch-clamp recording techniques.</p><p><strong>Results: </strong>Est 10 mumol.L-1 and 100 mumol.L-1 decreased the action potential duration, APD50, from (474 +/- 71) ms to (330 +/- 75) ms and (229 +/- 67) ms (n = 7 cells of 7 guinea pigs, P < 0.05), respectively. Est 100 mumol.L-1 also decreased APD90 from (587 +/- 60) ms to (418 +/- 79) ms (n = 7, P < 0.05). Est inhibited IK tail current (IK.tail) concentration-dependently. IK.tail was depressed 53% (n = 5, P < 0.05) at 10 mumol.L-1 and 80% (n = 5, P < 0.01) at 100 mumol.L-1 compared with control. Est > or = 10 mumol.L-1 blocked IK1. The maximal inhibition of inward current of IK1 occurred at -100 mV test potential was 49% (n = 5, P < 0.01) and outward current of IK1 at -40 mV was 72% (n = 5, P < 0.01). The reverse potential shifted negatively, from -70 to -76 mV.</p><p><strong>Conclusion: </strong>Est possessed blocking effects on both IK1 and IK channels in guinea pig ventricular myocytes.</p>","PeriodicalId":24002,"journal":{"name":"Zhongguo yao li xue bao = Acta pharmacologica Sinica","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1999-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Inhibitory effects of estradiol on inward rectifier and delayed rectifier K+ currents in guinea pig ventricular myocytes.\",\"authors\":\"Y Zhang, L L Song, S Z Gu, S G Lu, Z N Zhou\",\"doi\":\"\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Aim: </strong>To study the effects of estradiol (Est) on inward rectifier K+ (IK1) and delayed rectifier K+ (IK) channels in isolated guinea pig ventricular myocytes.</p><p><strong>Methods: </strong>Using whole cell patch-clamp recording techniques.</p><p><strong>Results: </strong>Est 10 mumol.L-1 and 100 mumol.L-1 decreased the action potential duration, APD50, from (474 +/- 71) ms to (330 +/- 75) ms and (229 +/- 67) ms (n = 7 cells of 7 guinea pigs, P < 0.05), respectively. Est 100 mumol.L-1 also decreased APD90 from (587 +/- 60) ms to (418 +/- 79) ms (n = 7, P < 0.05). Est inhibited IK tail current (IK.tail) concentration-dependently. IK.tail was depressed 53% (n = 5, P < 0.05) at 10 mumol.L-1 and 80% (n = 5, P < 0.01) at 100 mumol.L-1 compared with control. Est > or = 10 mumol.L-1 blocked IK1. The maximal inhibition of inward current of IK1 occurred at -100 mV test potential was 49% (n = 5, P < 0.01) and outward current of IK1 at -40 mV was 72% (n = 5, P < 0.01). The reverse potential shifted negatively, from -70 to -76 mV.</p><p><strong>Conclusion: </strong>Est possessed blocking effects on both IK1 and IK channels in guinea pig ventricular myocytes.</p>\",\"PeriodicalId\":24002,\"journal\":{\"name\":\"Zhongguo yao li xue bao = Acta pharmacologica Sinica\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1999-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Zhongguo yao li xue bao = Acta pharmacologica Sinica\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Zhongguo yao li xue bao = Acta pharmacologica Sinica","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Inhibitory effects of estradiol on inward rectifier and delayed rectifier K+ currents in guinea pig ventricular myocytes.
Aim: To study the effects of estradiol (Est) on inward rectifier K+ (IK1) and delayed rectifier K+ (IK) channels in isolated guinea pig ventricular myocytes.
Methods: Using whole cell patch-clamp recording techniques.
Results: Est 10 mumol.L-1 and 100 mumol.L-1 decreased the action potential duration, APD50, from (474 +/- 71) ms to (330 +/- 75) ms and (229 +/- 67) ms (n = 7 cells of 7 guinea pigs, P < 0.05), respectively. Est 100 mumol.L-1 also decreased APD90 from (587 +/- 60) ms to (418 +/- 79) ms (n = 7, P < 0.05). Est inhibited IK tail current (IK.tail) concentration-dependently. IK.tail was depressed 53% (n = 5, P < 0.05) at 10 mumol.L-1 and 80% (n = 5, P < 0.01) at 100 mumol.L-1 compared with control. Est > or = 10 mumol.L-1 blocked IK1. The maximal inhibition of inward current of IK1 occurred at -100 mV test potential was 49% (n = 5, P < 0.01) and outward current of IK1 at -40 mV was 72% (n = 5, P < 0.01). The reverse potential shifted negatively, from -70 to -76 mV.
Conclusion: Est possessed blocking effects on both IK1 and IK channels in guinea pig ventricular myocytes.