scholarly journals Induction of metabolic changes and down regulation of bovine parathyroid hormone-responsive adenylate cyclase are dissociable in isolated osteoclastic and osteoblastic bone cells.

1979 ◽  
Vol 254 (1) ◽  
pp. 34-37
Author(s):  
G.L. Wong
Keyword(s):  
Parathyroid Hormone ◽  
Adenylate Cyclase ◽  
Bone Cells ◽  
Metabolic Changes ◽  
Down Regulation ◽  
Bovine Parathyroid Hormone

Cyclic AMP Responses to Parathyroid Hormone and Glucagon during Lithium Treatment

1984 ◽  
Vol 66 (5) ◽  
pp. 557-559 ◽  
Author(s):  
D. G. Waller ◽  
J. D. M. Albano ◽  
J. G. B. Millar ◽  
A. Polak
Keyword(s):  
Parathyroid Hormone ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Intravenous Injection ◽  
Lithium Treatment ◽  
Endocrine Dysfunction ◽  
Urinary Cyclic Amp ◽  
Urine Concentrating Ability ◽  
Bovine Parathyroid Hormone

1. Inhibition of adenylate cyclase has been proposed as a mechanism for hypothyroidism and nephrogenic diabetes insipidus occurring during lithium treatment, but these disorders are rarely found in the same patients. 2. We have measured plasma levels of adenosine 3′:5′-cyclic monophosphate (cyclic AMP) after an intravenous injection of glucagon in eight patients receiving long term lithium treatment and in six control subjects. Urinary cyclic AMP levels after an intravenous injection of bovine parathyroid hormone (PTH) were also measured in the patients. 3. The plasma cyclic AMP response to glucagon in the patient group was significantly lower than that of the controls. No correlation was demonstrated between the plasma cyclic AMP response after glucagon and the urinary cyclic AMP response after PTH. 4. We have previously shown that impairment of the response to PTH correlates with reduced urine concentrating ability during lithium treatment. In contrast, there was no correlation between the responses to PTH and glucagon in individual patients. These results are consistent with the hypothesis that inhibition of adenylate cyclase is an important factor in lithium-induced endocrine dysfunction.

Comparison of renal and osseous binding of parathyroid hormone and hormonal fragments

1985 ◽  
Vol 249 (5) ◽  
pp. E437-E446 ◽  
Author(s):  
M. Demay ◽  
J. Mitchell ◽  
D. Goltzman
Keyword(s):  
Parathyroid Hormone ◽  
Adenylate Cyclase ◽  
Osteosarcoma Cells ◽  
Binding Studies ◽  
Intact Pth ◽  
Amino Terminal ◽  
Adenylate Cyclase Activation ◽  
Adenylate Cyclase Stimulation ◽  
Bovine Parathyroid Hormone ◽  
Stimulation Of

We compared receptor binding and adenylate cyclase stimulation of intact bovine parathyroid hormone (bPTH)-(1-84) and the synthetic amino-terminal fragments, bPTH-(1-34) and rat PTH (rPTH)-(1-34). Radioligands for binding studies were prepared by the lactoperoxidase technique and purified by high-pressure liquid chromatography. In both canine renal membranes and cloned rat osteosarcoma cells the amino-terminal fragments bound to a single order of sites; the affinity of rPTH-(1-34) exceeded that of bPTH-(1-34), correlating with its higher potency in stimulating adenylate cyclase. In studies with oxidized bPTH-(1--84), the middle and carboxyl regions of intact PTH were found to bind to both tissues but with higher affinity to osteosarcoma cells than to renal membranes. Our results demonstrate that rPTH-(1--34) is the most favorable probe of amino-terminal PTH binding and the most potent of the PTH peptides in stimulating renal and osseous adenylate cyclase. The results also show that midregion and carboxyl determinants within intact PTH contribute to hormone binding, which does not correlate with adenylate cyclase activation and appears more significant for skeletal than for renal binding.

Parathyroid hormone stimulates prostanoid formation in mouse calvarial bones

1989 ◽  
Vol 120 (3) ◽  
pp. 357-361 ◽  
Author(s):  
Östen Ljunggren ◽  
Ulf H. Lerner
Keyword(s):  
Parathyroid Hormone ◽  
Bone Resorption ◽  
Bone Cells ◽  
Neonatal Mouse ◽  
Dose Dependent ◽  
Bovine Parathyroid Hormone

Abstract. Bovine parathyroid hormone (bPTH 1–34) caused a time- and dose-dependent enhanced formation of the two prostanoids PGE2 and 6-keto-PGF1α in cultured neonatal mouse calvarial bones, with threshold for action at 0.1 nmol/l. The PGE2 response to PTH was completely blocked by indomethacin, but insensitive to calcitonin. By contrast, indomethacin was without effect on 45Ca release induced by PTH. The PTH analogues (Nle 8, 18, Tyr 34)-bPTH (3–34) amide and (Tyr 34)-bPTH (7–34) amide, which are putative PTH antagonists, did not affect basal production of PGE2, nor did the analogues affect bPTH 1–34 induced PGE2 formation. The data show that PTH stimulates prostanoid formation in mouse bone cells and that this response is not directly linked to PTH-induced bone resorption.

The biological properties of bovine parathyroid hormone (1–41), a fragment generated from the native hormone by human leukocytes

1987 ◽  
Vol 7 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Peter M. Barling ◽  
Carolyn Lowe
Keyword(s):  
Parathyroid Hormone ◽  
Adenylate Cyclase ◽  
Biological Activities ◽  
Human Leukocyte ◽  
Biological Properties ◽  
Osteosarcoma Cell ◽  
Reverse Phase Hplc ◽  
Leukocyte Elastase ◽  
Human Leukocyte Elastase ◽  
Bovine Parathyroid Hormone

Native bovine parathyroid hormone (bPTH) was found to be readily cleaved with human leukocyte elastase to yield the fragments bPTH(1–41) and bPTH(42–84). These were then isolated by reverse-phase HPLC and characterised by gas-phase sequencing and amino acid analysis. The biological activities of these fragments were assessed in an adenylate cyclase bioassay using the rat osteosarcoma cell line UMR106. bPTH(1–41) was found to have approximately twice the molar potency of the native hormone from which it was derived, bPTH(42–84) had no biological activity and did not modulate the adenylate cyclase response to these cells to the native hormone. The possible physiological significance of these observations is discussed.

Effect of Diphosphonates on Adenosine 3′:5′-Cyclic Monophosphate in Mouse Calvaria after Stimulation by Parathyroid Hormone in vitro

1976 ◽  
Vol 50 (6) ◽  
pp. 473-478
Author(s):  
U. Gebauer ◽  
R. G. G. Russell ◽  
M. Touabi ◽  
H. Fleisch
Keyword(s):  
Parathyroid Hormone ◽  
Bone Resorption ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Bone Cells ◽  
Essential Feature ◽  
Cyclic Monophosphate ◽  
Inhibit Bone Resorption ◽  
Mouse Calvaria

1. The diphosphonates, disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) and disodium dichloromethylene diphosphonate (Cl2MDP), inhibit bone resorption in animals and in explanted bone in tissue culture. The possibility that these effects might be due to inhibition of skeletal adenylate cyclase has been studied. 2. EHDP and Cl2MDP, added for 30 mm to the incubation medium at concentrations known to inhibit bone resorption, had no effect on basal content of adenosine 3′:5′-cyclic monophosphate (cyclic AMP) of mouse calvaria incubated in vitro, nor did they inhibit the rise in cyclic AMP induced by bovine parathyroid hormone. 3. Pretreatment of mice for 3 days with Cl2MDP also had no effect on cyclic AMP under basal conditions or after incubation of explanted calvaria with parathyroid hormone in vitro. EHDP under similar conditions slightly inhibited the increase induced by parathyroid hormone but had no effect on basal concentrations of cyclic AMP. 4. It is suggested that the inhibition of adenylate cyclase is not an essential feature of the reduction of bone resorption by diphosphonates, which may act by direct inhibitory effects on the dissolution of hydroxyapatite and perhaps by other unidentified effects on bone cells.

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