[The determination of cystine aminopoptidase (oxytocinase) with a ENI fast analyzer (author's transl)].

A procedure for the determination of cystine aminopeptidase activity was adapted to a fast analyzer. The various reaction parameters were checked. The precision of the method was about 5%. Cystine aminopeptidase activity was stable for long storage periods at +4 degrees C and -20 degrees C. The normal range for the terminal weeks of pregnancy was determined on samples from female patients with normal pregnancies.