正常孕妇血清血管紧张素转换酶活性的变化

THE INFLUENCE OF NORMOTENSIVE PREGNANCY ON ANGIOTENSIN-CON VERTING ENZYME ACTIVITY

血管紧张素转换酶是一种能将血管紧张素Ⅰ转换成血管紧张素Ⅱ并能灭活缓激肽的多肽酶。我们测定了88名正常非孕妇女及正常孕妇血清血管紧张素转换酶的活力,发现正常非孕妇女血清血管紧张素转换酶活性水平为69.39±12.90(n=21),早孕妇女为66.72±12.45(n=23)(与非孕相比差异不显著,P>0.05),中孕妇女为58.33±12.64(n=28)(与非孕相比差异非常显著,P<0.01),晚孕妇女为52.36±9.91(n=16)(与非孕相比差异非常显著,P<0.01)。血清血管紧张素转换酶活性水平在妊娠期间与孕周的增长呈相关关系(Y=71.34—0.56X,r=0.44,n=67,P<0.01)。结果提示血管紧张素转换酶活性随孕周的增加而降低。尽管这种酶活力降低的原因还不清楚,但酶的抑制在妊娠期间对维持血压稳定、保证子宫胎盘的血液供应具有重要生理意义。

Serum angiotensin-converting enzyme (SACE), the polypeptide that converts angiotensin Ⅰ to angiotensin Ⅱand inactivates bradykinin (BK), was measured in the serum of 88 non-pregnant women and normotensive pregnant women using sensitive colorimctric micromethod.The level of the SACE activity in nonpregnant women (69.39±12.9U, n =21) was higher than those in first trimester pregnant women (66.72±12.45 U, n = 23, P>0.05), second trimester pregnant women(58.33±12.64 U, n=28, P<0.01) and third trimester pregnant women ( 52.36±9.91 U, n = 16, P<0.01).There was correlation between SACE activity and the gestation period (weeks) (Y = 71.34-0.56X, r = 0.44,n = 67, P<0.01).From these results it seems that ACE activity was decreased as the week of gestation increased.Although the reason for the reduced level of SACE in pregnant women is not known, the inhibition of the ACE activity during pregnancy has physiologic importance for keeping the balance of blood pre-sure and increasing the blood flow to the uterus and placenta.