Production of active and acid-activated renin by cultured explants of human fetal tissues.

Various fetal tissues with gestational ages that ranged from 6 to 22 weeks were cultured as explants, and the culture media were examined for the production of both active and acid-activated renin. Media from cultures of fetal kidney, both the male and female genital tracts, and umbilical cord vessels were found to contain large quantities of active and acid-activated renin. Consistent differences in the production patterns of renin were found between the tissues, which may reflect the different potentials of the tissues to produce renin in vivo.