Cathepsin D coexists with renin in the secretory granules of juxtaglomerular epithelioid cells

Abstract
Mature juxtaglomerular epithelioid cell secretory granules of the rat exhibit both renin-and cathepsin D-like immunoreactivity. On the basis of the coexistence with renin at a pH which, according to previous experiments, is probably in the range of that in lysosomes, cathepsin D is suggested to be involved in the regulation of the granular renin stores available for secretion.