Concentrations of angiotensin-converting enzyme in tissues of the rat

摘要: Angiotensin-converting enzyme, the peptidase which transforms inactive decapeptide, angiotensin I, to pressor octapeptide, II, was measured in homogenates of 25 rat tissues, using a spectrophotometric assay for hydrolysis hippuryl-L-histidyl-L-leucine. Most tissues studied contained measurable converting enzyme activities that were dependent upon added Cl−, stimulated by Co2+, and inhibited specific pentapeptide inhibitor from venom Bothrops jararaca, pyrrolidone carboxylyl-L-lysyl-L-tryptophyl-L-analyl-L-proline. High found lung segments digestive tract, but highest testis epididymis, associated with tubular fluids, not sperm cells. The activity increased markedly during maturation intact, hypophysectomized, rats.