Disease relevance of Pthr1

• Effect of transforming growth factor beta on parathyroid hormone receptor binding and cAMP formation in rat osteosarcoma cells [1].
• Chronic renal failure (CRF) is associated with resistance to the action of a variety of hormones, a rise in [Ca2+]i and decrease in the amount of mRNA of one hormone receptor, the PTH-PTHrP receptor [2].
• Downregulation of parathyroid hormone receptor gene expression and osteoblastic dysfunction associated with skeletal resistance to parathyroid hormone in a rat model of renal failure with low turnover bone [3].
• Data on the effect of hypoparathyroidism on basal levels of [Ca2+]i are not available, while those on the mRNA of the PTH-PTHrP receptor are variable [4].

High impact information on Pthr1

• Alterations in hormonal responses were not due to changes in parathyroid hormone receptor number or binding kinetics nor to alterations in adenylyl cyclase activity [5].
• Characterization of fully active biotinylated parathyroid hormone analogs. Application to fluorescence-activated cell sorting of parathyroid hormone receptor bearing cells [6].
• Immunofluorescence studies showed that nuclear accumulation of PTH1R was associated with specific stages of the cell cycle [7].
• Down-regulation of PTH-PTHrP receptor of heart in CRF: role of [Ca2+]i [8].
• The treatment of CRF rats with verapamil normalized [Ca2+]i of cardiac myocytes and returned the mRNA of their PTH-PTHrP receptor towards normal levels, despite marked elevation of blood levels of PTH.(ABSTRACT TRUNCATED AT 250 WORDS)[8]

Biological context of Pthr1

• We report the in vivo whole body distribution and blood plasma pharmacokinetics of the parathyroid hormone receptor antagonist [Nle8,18,D-Trp12,monoiodinated Tyr34]bPTH(7-34)amide to determine parameters that are likely to affect its administration regimen [9].
• Intron positions were similar to the positions of introns in growth hormone-releasing hormone receptor and parathyroid hormone receptor, two receptors belonging to the same receptor family as the glucagon receptor [10].
• Identification of the promoter region of the parathyroid hormone receptor gene responsible for transcriptional suppression by insulin-like growth factor-I [11].

Anatomical context of Pthr1

• Biochemical and morphological characterization of parathyroid hormone receptor binding to the rat osteosarcoma cell line UMR-106 [12].
• In another population, parathyroid hormone receptor, alkaline phosphatase, and osteocalcin were also expressed at levels almost equal to those observed in long bone-derived osteoblasts [13].
• At 2 days postirradiation, the decrease in parathyroid hormone-related protein and parathyroid hormone receptor 1 expression in the irradiated growth plate transitional and hypertrophic zones was reversed in both of the combination groups but persisted in the groups treated with the individual drugs [14].
• We found that mRNA for the PTH-PTHrP receptor is present in the heart, brain, spleen, lung, liver, skeletal muscle, kidney and testis [15].
• This suggests that mechanical compression influences chondrocytes of the hypertrophic zone to alter their expression of specific genes encoding proteins of the extracellular matrix, while PTH-PTHrP receptor mRNA, a regulatory protein, remained unaffected by loading [16].

Associations of Pthr1 with chemical compounds

• Neither receptor can modify parathyroid hormone receptor-mediated elevation of cellular cyclic AMP [17].
• The present study was performed to measure [Ca2+]i in renal cells, to estimate the concentrations of mRNA of the PTH-PTHrP receptor in kidney, liver, and heart, and to examine the phosphaturic response to PTH and adenine 3',5'-cyclic monophosphate (cAMP) in normal rats as well as in animals after 3 weeks of parathyroidectomy (PTX) [4].
• In contrast, OP-1 treatment stimulated phenotypic differentiation in ROS 17/2.8 cells, as indicated by enhanced 1) alkaline phosphatase activity (4-fold); 2) alkaline phosphatase mRNA (5-fold); 3) parathyroid hormone receptor mRNA (2-fold), and 4) parathyroid hormone-stimulated adenosine 3',5'-cyclic monophosphate accumulation (2-fold) [18].

Regulatory relationships of Pthr1

• TGF-beta1 stimulated a 2-7-fold increase in steady state mRNA levels for the parathyroid hormone receptor at a maximal dose of 5 ng/ml, with increased levels of expression at 6 h of TGF-beta1-incubation, and peak levels at 8-24 h [19].

Other interactions of Pthr1

• When the immunoprecipitates were separated and subsequently exposed to biotinylated PTH (1-84) a single band was present on the gel at 66.3 kDa, corresponding to the PTH1R [7].
• Role of protein kinase A, phospholipase C and phospholipase D in parathyroid hormone receptor regulation of protein kinase Calpha and interleukin-6 in UMR-106 osteoblastic cells [20].
• Type I collagen substrate increases calcitonin and parathyroid hormone receptor-mediated signal transduction in UMR 106-06 osteoblast-like cells [21].
• The relative amounts of mRNA of the PTH-PTHrP receptor to that of beta-actin in both kidney and liver of CRF rats were significantly (p < 0.01) lower than in normal animals [22].

Analytical, diagnostic and therapeutic context of Pthr1

• Using immunoprecipitation and affinity chromatography, we show that the PTH1R forms a complex with the importin family of transport molecules [7].
• Immunoprecipitation of the parathyroid hormone receptor [23].
• The parathyroidectomy of CRF rats prevented the rise in blood PTH levels and normalized [Ca2+]i of cardiac myocytes and returned the mRNA of their PTH-PTHrP receptor towards normal levels [8].
• After transplantation in vivo, the expression of OC and PTHR decreased to undetectable levels [24].
• Poly A+RNA from a variety of rat tissues was probed with a 1,200-bp fragment of the cDNA of the PTH-PTHrP receptor by the Northern blot technique [15].

References