内皮依赖性超极化因子对离体家兔肠系膜动脉张力的影响  

Effects of Endothelium-derived Hyperpolarizing Factor on Tension of Isolated Rabbit Mesentery Artery

作　　者：张秀荣[1] 刘跃春[1] 高尔[1] 

机构地区：[1]潍坊医学院应用药理学实验室,山东潍坊261042

出　　处：《潍坊医学院学报》2004年第1期15-18,共4页Acta Academiae Medicinae Weifang

摘　　要：目的　探讨内皮依赖性超极化因子 (EDHF)对血管平滑肌张力的影响。方法　采用家兔离体肠系膜动脉 (MA)灌流方法 ,在一氧化氮合酶 (NOS)抑制剂左旋硝基精氨酸 (L NNA ,30 0 μmol L)和环氧合酶抑制剂消炎痛 (Indo ,7μmol L)存在的条件下 ,观察乙酰胆碱 (Ach)引起的血管内皮依赖性超极化因子对血管张力的影响并分析其作用机制。结果　①当L NNA和Indo存在时 ,在U46619(30nmol L)引起血管收缩的基础上 ,Ach仍可引起家兔MA的内皮依赖性舒张 ,去除内皮后可消除此舒张作用 (P <0 .0 1)。②血管内皮完整时 ,于L NNA和Indo存在的情况下 ,预先用KCa通道阻断剂四乙铵 (TEA ,1mol L)可阻断Ach引起的内皮依赖性舒张 (P <0 .0 1) ;而预先用KATP通道阻断剂格列苯脲 (GBM ,3μmol L)却不能阻断此舒张作用 (P >0 .0 5 )。③血管内皮完整时 ,L NNA和Indo存在的情况下 ,细胞色素P450 (CytP450 )阻断剂克霉唑 (CMZ ,3μmol L)可显著抑制Ach引起的内皮依赖性舒张(P <0 .0 1)。结论　EDHF与花生四烯酸的CytP450 代谢途径有关 ,它所介导的动脉舒张可能与KCa通道有关。Objective This study was designed to observe the effects of endothelium-derived hyperpolarizing factor (EDHF) on the tension of rabbit mesentery arteries in vitro and to probe the mechanism of vessel relaxation induced by EDHF.Methods Treated with NOS inhibitor NG-nitro-L-arginine (L-NNA,300μmol/L) and cyclooxygenase inhibitor indomethacin (Indo,7μmol/L) for 30 min,rabbit mesentery artery rings were studied in organ chambers.Relaxation of the artery and the underlying mechanism were analyzed.Results ①Precontracted by U 46619 (30nmol/L),the mesentery artery was relaxed by Ach in the resistance of L-NNA and Indo,and the relaxation disappeared after the removal of endothelium.②In the present of L-NNA and Indo,the endothelium-dependent relaxation induced by Ach was inhibited by the Ca 2+ -activated K channel (KCa) inhibitor tetraethylam monium(TEA,1mmol/L),but the adenosine triphosphate-senstive K channel(K ATP ) inhibitor glibenclamide(GBM,3 μmol/L) had few effects on the relaxation induced by Ach.③In the endothelium intact arterial rings,the endothelium-dependent relaxation induced by Ach at the present of L-NNA and Indo was significantly inhibited by cytochrome P 450 inhibitor clotrimazole(CMZ,3 μmol/L).Conclusion The results suggest that endothelium-derived hyperpolarizing factor-mediated relaxation in rabbit arteries is related to KCa channel and that EDHF may be a cytochrome P 450 mono-oxygenase metabolite of arachidomic acid.

关 键 词：动脉 骨皮依赖性舒张 内皮依赖性超极化因子 家兔 

分 类 号：R322.12[医药卫生—人体解剖和组织胚胎学]