血管紧张素1-7和乙酰胆碱调节大鼠主动脉舒张作用的差异

Difference of regulation of angiotensin1-7 and achtylcholine on relaxation of rats aorta

目的探讨血管紧张素1-7和乙酰胆碱对血管紧张素Ⅱ及苯肾上腺素引起的缩血管效应的舒张作用的差异。方法用恒温[(37±0.5)℃]灌流装置测定乙酰胆碱或血管紧张素1-7引起的大鼠胸主动脉血管环舒张反应。结果乙酰胆碱抑制苯肾上腺素引起的大鼠主动脉收缩反应的作用比血管紧张素1-7强(P<0.05),乙酰胆碱和血管紧张素1-7的半数有效抑制浓度分别是[(175±36)×10-9]mol.L-1和[(227±14)×10-9]mol.L-1;而对血管紧张素Ⅱ引起的大鼠主动脉收缩反应,血管紧张素1-7的抑制作用比乙酰胆碱强(P<0.05),它们的半数有效浓度分别是[(157±8)×10-9]mol.L-1和[(273±12)×10-9]mol.L-1。结论血管紧张素1-7对血管紧张素Ⅱ诱导的血管收缩的舒张作用比乙酰胆碱强,而对苯肾上腺素诱导的血管收缩的舒张作用则比乙酰胆碱弱。

Objective To explore the relaxation effect of angiotensin1-7 （ Ang1-7 ） or acetylcholine （Ach） on rats aorta contraction,which were induced by angiotensin Ⅱ or phenyladrenalin. Methods Aorta of rats were placed in constant temperature [ （ 37 ± 0.5 ） ℃ ] filling device, and the relaxation reaction induced by Ang1-7 or Ach was recorded by physiological recorder. Results The inhibition effect of Ach on the aorta contaction induced by phenyladrenalin was stronger than Ang1-7 （ P 〈 0.05 ） , their half concentrations of inhibition （ IC50 ） were[ （ 175 ±36） × 10^-9] mol·L^-1 and[ （227 ± 14） × 10^-9] mol·L^-1 The inhibition effect of Ang1-7 on the aorta contraction induced by anyiotensin Ⅱ was stronger than Ach （P 〈 0.05 ）, and their ICsowere [ （157 ± 8 ） × 10^-9] mol·L^-1and [ （273 ± 12） × 10^-9] mol·L^-1 respectively. Conclusion The relaxation effect of Ang1-7 on rats aorta contraction induced by angiotensin Ⅱ was stronger, but weaker when the contraction was induced by phenyladrenalin, than acetylcholine.