title: Depression of calcium pump activity in renal cortex of vitamin D-deficient rats with secondary hyperparathyroidism.
abstract: To examine the hormonal regulation of the ATP-dependent Ca2+ pump in the kidneys, the ATP-dependent Ca2+ uptake by the basolateral membrane vesicles in the renal cortex was measured using radioactive calcium (45Ca2+) in rats with vitamin D deficiency or rats undergoing thyroparathyroidectomy. The Vmax of the Ca2+ pump activity was increased not only by administering calcitriol, but also by normalizing the serum calcium level in vitamin D-deficient rats. PTH suppressed the Ca2+ pump activity in normocalcemic vitamin D-deficient rats. Thyroparathyroidectomy did not affect the Ca2+ pump activity in the kidneys of normal rats. It was concluded that the ATP-dependent Ca2+ pump activity was depressed by secondary hyperparathyroidism in vitamin D-deficient rats.
authors.affiliation: Department of Medicine, Kitasato University School of Medicine, Kanagawa, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tsukamoto
authors.forename: T
authors.initials: T
authors.lastname: Tamura
authors.forename: M
authors.initials: M
authors.lastname: Saitoh
authors.forename: Y
authors.initials: Y
authors.lastname: Takita
authors.forename: T
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002117:Calcitriol / Q000494:pharmacology; D002118:Calcium / Q000097:blood / Q000378:metabolism; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002132:Calcium Radioisotopes; D002462:Cell Membrane / Q000378:metabolism; D006962:Hyperparathyroidism, Secondary / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism*; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood / Q000494:pharmacology; D016105:Parathyroidectomy; D051381:Rats; D011919:Rats, Inbred Strains; D013965:Thyroidectomy; D014808:Vitamin D Deficiency / Q000150:complications / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D002132:Calcium Radioisotopes; D010281:Parathyroid Hormone; D000255:Adenosine Triphosphate; D002117:Calcitriol; D002118:Calcium