title: Endothelin receptors in human parathyroid gland.
abstract: We studied whether specific receptors for endothelins (ETs) exist in human parathyroid tissues and whether ETs may have any effect on secretion of PTH from parathyroid cells. Binding studies using [125I]ET-1 to the parathyroid membranes obtained from patients with hyperparathyroidism (2 adenomas, 2 hyperplasias) revealed that ET-1 competitively inhibited the binding of [125I]ET-1 to the membranes (the apparent Kd: 62 +/- 18 pM), whereas ET-3 showed biphasic and less steep inhibition curve than ET-1 in all tissue membranes examined. Northern blot analysis of poly(A)+ RNA from the parathyroid adenoma clearly demonstrated gene expression of both ETA and ETB receptors as well as preproET-1. ET-1 inhibited basal PTH secretion from dispersed adenoma cells more potently than ET-3. The present study clearly demonstrates the presence of both ETA and ETB receptor subtypes in human parathyroid tissues through which ETs may modulate PTH secretion in an autocrine and/or paracrine manner.
authors.affiliation: Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Eguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Hirata
authors.forename: T
authors.initials: T
authors.lastname: Imai
authors.forename: K
authors.initials: K
authors.lastname: Kanno
authors.forename: T
authors.initials: T
authors.lastname: Akiba
authors.forename: A
authors.initials: A
authors.lastname: Sakamoto
authors.forename: M
authors.initials: M
authors.lastname: Yanagisawa
authors.forename: T
authors.initials: T
authors.lastname: Masaki
authors.forename: F
authors.initials: F
authors.lastname: Marumo
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000601:surgery; D001667:Binding, Competitive; D015152:Blotting, Northern; D016232:Endothelins / Q000378:metabolism*; D006801:Humans; D006961:Hyperparathyroidism / Q000378:metabolism / Q000601:surgery; D006965:Hyperplasia; D007700:Kinetics; D010280:Parathyroid Glands / Q000378:metabolism* / Q000473:pathology; D010282:Parathyroid Neoplasms / Q000235:genetics / Q000378:metabolism / Q000601:surgery; D016105:Parathyroidectomy; D011061:Poly A / Q000235:genetics / Q000302:isolation & purification; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D017466:Receptors, Endothelin; D014407:Tumor Cells, Cultured
chemical_list: D016232:Endothelins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D011061:Poly A; D012313:RNA