Kininogenase activity in rat uterus homogenates.

A synthetic peptide substrate for tissue kallikreins was hydrolysed by uterus homogenates. These also released kinins when incubated with dog kininogen. By using high pressure liquid chromatography in combination with a radioimmunoassay for kinins, the peptides released were identified as bradykinin and kallidin. Plasma kallikrein and trypsin released bradykinin from dog kininogen and hog pancreas kallikrein released kallidin from this substrate. This suggests that a tissue kallikrein and also a trypsin-like enzyme or perhaps plasma kallikrein are present in rat uterus.