title: Clonal rat parathyroid cell line expresses a parathyroid hormone-related peptide but not parathyroid hormone itself.
abstract: A novel parathyroid hormone-related peptide has been identified in tumors associated with the syndrome of humoral hypercalcemia of malignancy. Subsequently, mRNAs encoding this peptide have been found to be expressed in a number of normal tissues, including the parathyroids. Using Northern blotting, RNase protection, and immunochemical techniques, we examined a clonal rat parathyroid cell line originally developed as a model system for studying parathyroid cell physiology. We found that this line expresses the parathyroid hormone-related peptide but not parathyroid hormone itself. Secretion of the parathyroid hormone-related peptide varied inversely with extracellular calcium concentration, but neither calcium nor 1,25-dihydroxyvitamin D3 appeared to influence steady-state parathyroid hormone-related peptide mRNA levels. This clonal line may prove to be an interesting system for studying the factors responsible for tissue-specific parathyroid hormone and parathyroid hormone-related peptide gene expression.
authors.affiliation: Department of Medicine, Yale University, New Haven, CT 06510.
authors.forename: K
authors.initials: K
authors.lastname: Ikeda
authors.forename: E C
authors.initials: EC
authors.lastname: Weir
authors.forename: K
authors.initials: K
authors.lastname: Sakaguchi
authors.forename: W J
authors.initials: WJ
authors.lastname: Burtis
authors.forename: M
authors.initials: M
authors.lastname: Zimering
authors.forename: M
authors.initials: M
authors.lastname: Mangin
authors.forename: B E
authors.initials: BE
authors.lastname: Dreyer
authors.forename: M L
authors.initials: ML
authors.lastname: Brandi
authors.forename: G D
authors.initials: GD
authors.lastname: Aurbach
authors.forename: A E
authors.initials: AE
authors.lastname: Broadus
mesh_terms: D000818:Animals; D002460:Cell Line; D002999:Clone Cells / Q000378:metabolism; D005786:Gene Expression Regulation; D006934:Hypercalcemia / Q000235:genetics / Q000378:metabolism; D006965:Hyperplasia; D010280:Parathyroid Glands / Q000378:metabolism / Q000473:pathology*; D010281:Parathyroid Hormone / Q000235:genetics / Q000302:isolation & purification*; D010446:Peptide Fragments / Q000235:genetics / Q000302:isolation & purification*; D012333:RNA, Messenger / Q000302:isolation & purification; D011863:Radioimmunoassay; D051381:Rats; D014158:Transcription, Genetic
chemical_list: D010281:Parathyroid Hormone; D010446:Peptide Fragments; D012333:RNA, Messenger