内皮素拮抗剂对大鼠硝酸甘油耐药性的影响

目的: 探讨内皮素受体拮抗剂Bosentan对大鼠硝酸甘油耐药的改善作用.方法: Wistar 大鼠28只,随机分成对照组(C组,n=10),硝酸甘油组(NTG组,n=6), Bosentan组(n=6),硝酸甘油+Bosentan组(NTG+Bosentan组,n=6).观察各组大鼠对硝普钠(SNP)的降压反应.用放射免疫方法测定各组血浆和血管组织的内皮素-1(ET-1) 含量.结果: NTG组大鼠对SNP的降压反应最弱,NTG +Bosentan组大鼠对SNP的降压反应明显强于NTG 组大鼠, NTG +Bosentan组大鼠离体主动脉环对不同浓度SNP的舒张反应较NTG组大鼠有明显的改善. NTG +Bosentan组大鼠血浆及血管组织ET-1含量与NTG组大鼠比较差异无显著性,均明显高于C组大鼠.结论:内皮素受体拮抗剂Bosentan可以改善NTG耐药的发生.

Effect of endothelin receptor antagonist on nitroglycerin tolerance in rats

Objective: To investigate whether endothelin receptor antagonist Bosentan could reduce the nitroglycerin(NTG) tolerance in rats . Methods: Twenty-eight wistar rats were divided into control group(n=10),Nitroglycerin(NTG) group(n=6), Bosentan group (n=6)and NTG+Bosentan group(n=6).The hypotensive response to sodium nitroprusside(SNP) in different group rats,and the relaxation effect of different concentrations of SNP on isolated aortic rings from different group rats were observed .The endothelin-1 (ET-1) contents of plasma and vascular tissue were measured by the radioimmuno assay method. Results: The hypotention response to SNP was significantly attenuated in NTG group,compared with control group. The hypotensive response to SNP was improved in NTG+Bosentan group, compared with NTG group .The relaxation effect of SNP on isolated rat aortic ring was obviously restored in NTG+Bosentan group,compared with NTG group. The ET-1 contents of plasma and vascular tissue were markedly increased in both NTG+Bosentan group and NTG group compared with control group. Conclusion: Endothelin receptor antagonist Bosentan can prevent against the NTG tolerance .