Renin and cathepsin B in human pituitary lactotroph cells. An ultrastructural study.
Renin, prorenin and cathepsin B were localized in human lactotrophs using immunoelectron microscopic techniques. Renin and prorenin were found in numerous cytoplasmic granules. Cathepsin B, a lysosomal enzyme known to be able to activate prorenin into renin, was also present in cytoplasmic granules of lactotrophs. The co-localization of renin and prolactin in the same secretory granules was demonstrated by double immunolabelling. Renin and cathepsin B were co-localized in some granules by the same technique. These results suggest a local activation of renin in the secretory granules of lactotrophs and support the hypothesis of a possible autocrine action of the renin-angiotensin system on prolactin release.
Saint-André
J P
JP
Laboratoire d'Anatomie Pathologique, Centre Hospitalier Universitaire, Angers, France.
Rohmer
V
V
Pinet
F
F
Rousselet
M C
MC
Bigorgne
J C
JC
Corvol
P
P
D000236:Adenoma / Q000378:metabolism; D002403:Cathepsins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D010902:Pituitary Gland / Q000378:metabolism* / Q000473:pathology; D010911:Pituitary Neoplasms / Q000378:metabolism; D012083:Renin / Q000378:metabolism*
D002403:Cathepsins; D012083:Renin