AJP - Endocrinology and Metabolism, Vol 252, Issue 4 E509-E518, Copyright © 1987 by American Physiological Society
The cat: an animal model for studies of inactive renin
N. Glorioso, C. Troffa, J. H. Laragh, S. A. Atlas, D. Marion and J. E. Sealey
Inactive renin, prorenin, is found in high concentrations in human plasma.
We report herein the characteristics of trypsin-activated inactive renin
from cat kidney and plasma. Cat and human plasma inactive renin were
activated by similar concentrations of trypsin. As in humans, there was
more inactive than active renin in cat plasma; also, inactive renin was low
but detectable after nephrectomy. Trypsin-activated renal inactive renin,
purified on Cibacron blue agarose and pepstatin-amino-hexyl-Sepharose
chromatography, was inhibited by pepstatin and by a renin inhibitor
similarly to cat and human active renins. The pH optimum of cat renin was
biphasic: the higher peak of active renin was at pH 5.7, whereas that of
activated inactive renin was at pH 7.5. As in humans, active and inactive
plasma renin increased during sodium depletion and inactive renin increased
during beta-adrenergic blockade, while active renin decreased. These
results demonstrate that cat inactive renin is similar to human prorenin.
Therefore, the cat may be a useful model for the study of prorenin.
