Renin in the human kidney

Summary We have localized the enzyme renin (EC 3.4.99.19) in the normal adult human kidney by immunohistology. Serial paraffin sections of kidneys were incubated with renin antisera and then processed by the peroxidase-antiperoxidase method. Renin immunoreactivity was observed in the juxta-glomerular epithelioid granular cells (JEG-cells) in the wall of the afferent and rarely of the efferent vessel of the glomerulus. JEG-cells have long cytoplasmic processes penetrating between adjacent cells. This suggests a possible paracrine release of renin. Staining of various segments of the tubular system was shown to be artifactual. The kidney proteins recognized by our anti-human renin antisera had similar characteristics to renin when determined by a combination of gel-electrophoretic and immunologic techniques. Renin immunostaining in the juxtaglomerular apparatus of the human kidney is discrete and reflects the low amount of extractable renin.Dedicated to Prof. G. Töndury on the occasion of his 75th birthday     

Renin in the uterus of non-pregnant mice

Summary The distribution of renin in the uterus of non-pregnant mice was studied by immunocytochemistry, using the peroxidase-antiperoxidase (PAP) technique, by electron microscopy and biochemical renin estimation. By immunocytochemistry, two separate localizations of renin could be identified, one in the apical region of the endometrial cells, the other in perivascular cells of the myometrium. The renin concentration in the endometrium, as determined cytochemically, and the total renin content of the uterus, as estimated enzymatically, varied with the ovarian cycle, being highest during the oestrus and lowest during the post-oestrus phase. The electronmicroscopic finding of fluctuations in the granule content of the epithelial cells was in accordance with the immunocytochemical and biochemical data.These studies were supported by the Deutsche Forschungsgemeinschaft with the SFB 90 Cardiovasculäres System