Angiotensin-converting enzyme localized in the rat pituitary and adrenal glands by [3H]captopril autoradiography.
We have localized angiotensin-converting enzyme (EC 3.14.5.1) in the rat pituitary and adrenal glands by [3H]captopril autoradiography. The maximal numbers of [3H] captopril-binding sites are: posterior pituitary, 4500 fmol/mg protein; anterior pituitary, 1950 fmol/mg; intermediate pituitary, less than 100 fmol/mg; adrenal medulla, 480 fmol/mg; and adrenal cortex, less than 25 fmol/mg. The distribution within the posterior pituitary and adrenal medulla is homogeneous, whereas that in the anterior pituitary is patchy. Subcellular fractionation of the bovine adrenal medulla reveals enrichment of angiotension-converting enzyme in plasma membrane fractions, but not in chromaffin granules. [3H]Captopril autoradiography in the rat pituitary gland is unaltered by dehydration, adrenalectomy, or reserpine treatment and in Brattleboro rats. [3H]Captopril binding in the adrenal medulla is increased by 75% 3 weeks after hypophysectomy and is elevated by 80% after reserpine treatment. The change after hypophysectomy is not reversed by dexamethasone treatment.
D000311:Adrenal Glands / Q000201:enzymology*; D000313:Adrenal Medulla / Q000201:enzymology; D000818:Animals; D001345:Autoradiography; D002216:Captopril / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006651:Histocytochemistry; D007016:Hypophysectomy; D008297:Male; D008722:Methods; D007703:Peptidyl-Dipeptidase A / Q000032:analysis*; D010902:Pituitary Gland / Q000201:enzymology*; D051381:Rats; D011910:Rats, Brattleboro; D011919:Rats, Inbred Strains; D012110:Reserpine / Q000494:pharmacology; D013997:Time Factors
D012110:Reserpine; D002216:Captopril; D007703:Peptidyl-Dipeptidase A