Abstract
A rapid method for estimation of cystine aminopeptidase activity (CAP) in the serum of pregnant women is presented. The method takes only 3 hours and 10–15 samples can be estimated simultaneously. Using this method the CAP activity has been estimated in about 700 blood samples from non-pregnant and pregnant women. The CAP activity was estimated to 0.12±0.012 mU/ml serum in non-pregnant women (n=12), 0.80±0.08 mU/ml serum in the 21st week of pregnancy (n=15) and 5.72±0.29 mU/ml serum in the 40th week of pregnancy (n=36) which implies a 50-fold increase of the enzyme activity during pregnancy. The method can be a valuable parameter in judging the length of pregnancy between 21–37 week of pregnancy and preliminary studies indicate that the method might be of value to detect placental insufficiency in the third trimester.