Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tritiated salmon calcitonin was prepared by methylation of the free amino groups using tritiated sodium borohydride as precursor. Specific radioactivity was measured in competitive inhibition studies with specific anticalcitonin antibodies or tubular membranes as binding sites for calcitonin. The value observed, approx. 4 Ci/mmol, corresponded to methylation of one third of the available N-H bonds. Tritiated calcitonin prepared in this way retained full biological activity as assessed in vitro by stimulation of adenylate cyclase and in vivo by rat bioassay. Tritiated calcitonin specifically bound to isolated renal cells and nonspecific binding did not exceed 10% of total binding. Equilibrium was obtained after 15 min incubation. The hormone-receptor complex could be dissociated in the presence of an excess of unlabelled calcitonin. This data shows that tritiated calcitonin can be used in metabolic and receptor studies.
Mol Cell Endocrinol 1977 Sep
PMID:Biological and immunological properties of tritiated salmon calcitonin. 20 May 9

Recently we developed a system for studying concurrent secretion of calcitonin (CT)and parathyroid hormone(PTH)in vitro from single rat thyroparathyroid gland complexes. In the present study, mechanisms involved in secretion of CT and PTH were explored by altering the medium [Ca ] and by using the Ca antagonist, verapamil. We also re-examined the idea that cyclic nucleotides may help regulate secretion of these hormones and attempted to determine if effects of cyclic nucleotides might be altered by changes in medium [Ca]. Thyroparathyroid glands from 8-day-old rats were incubated in serum-free medium for 8h, and CT and PTH levels in the medium were measured by radioimmunoassays. We show for the first time that: (1) although low [Ca] is well known to promote PTH release, some extracellular Ca is needed for PTH secretion to occur at a maximal rate; (2) inhibition of Ca entry into cells with verapamil mimics the effects of low medium Ca on both CT and PTH release; and (3) cyclic nucleotides may exert their effects on secretion of CT and PTH at least in part via effects on Ca entry into cells.
Mol Cell Endocrinol 1979 Jun
PMID:Effects of calcium and cyclic nucleotides on rat calcitonin and parathyroid hormone secretion. 22 3

1. Plasma concentrations of human calcitonin were measured in groups of patients with chronic renal failure, treated either conservatively or by haemodialysis, and compared with a normal group of persons. 2. Plasma calcitonin was statistically significantly elevated in both groups with renal failure. 3. When the data from the three groups were pooled, plasma calcitonin was found to be inversely correlated with total calcium and directly correlated with plasma creatinine.
Clin Sci Mol Med 1977 Jun
PMID:Plasma calcitonin in chronic renal failure: relation to other factors of importance in bivalent ion metabolism. 32 18

Removal of the thyroid in normocalcemic rats with functional parathyroid transplants was found to reduce the hepatocyte DNA synthetic activity which normally follows partial hepatectomy. This proliferative incapacitation of hepatocytes appeared to be due specifically to a calcitonin deficiency since it was overcome by a single injection of pure synthetic salmon calcitonin shortly after partial hepatectomy. Salmon calcitonin and bovine parathyroid hormone were equally able to reverse the similar proliferative incapacitation of hepatocytes in hypocalcemic rats which had both their parathyroid and thyroid glands removed one day before partial hepatectomy. However, these two hormones (individually or together) could not reverse the proliferative incapacity resulting from a more prolonged (3-day) exposure to the hypocalcemic conditions in thyroparathyroidectomized rats, but the proliferative incapacity could be reversed by simultaneous treatment with the vitamin D3 metabolite, 1 alpha,25-dihydroxycholecalciferol. We suggest that extracellular calcium ions are the actual regulators of this hormonally-controlled hepatocyte proliferative development and that parathyroid hormone and the vitamin D3 metabolite affect proliferation indirectly by determining the extracellular calcium concentration, while calcitonin directly, or indirectly, sensitizes hepatocytes to the action of calcium.
Mol Cell Endocrinol 1979 Aug
PMID:The control of liver regeneration by calcitonin, parathyroid hormone and 1 alpha,25-dihydroxycholecalciferol. 49 50

1. Blood flow to the skeleton was measured by the 18F clearance method of Wooton, Reeve & Veall (1976) in 24 patients with untreated Paget's disease. In every patient but one, resting skeletal blood flow was increased. There was a significant positive correlation between skeletal blood flow and serum alkaline phosphatase and between skeletal blood flow and urinary total hydroxyproline excretion. 2. Fourteen patients were re-studied after they had received short-term (7 days or less) or long-term (7 weeks or more) calcitonin. Skeletal blood flow, alkaline phosphatase and urinary hydroxy-proline excretion fell towards normal in every case. There was some evidence from the short-term studies that calcitonin produced a more rapid fall in skeletal blood flow than in alkaline phosphatase. 3. Glomerular filtration rate appeared to increase transiently in response to calcitonin.
Clin Sci Mol Med 1978 Jan
PMID:Skeletal blood flow in Paget's disease of bone and its response to calcitonin therapy. 62 Apr 95

The possibility of calcitonin (CT) degradation by thyroid tissue in vitro was investigated. Tissue slices or a thyroid supernatant solution was incubated with 131I-labeled porcine CT for 30--60 min at 37 degrees C. Calcitonin degradation and deiodination were determined by chromatoelectrophoresis and/or quso adsorption. Degradation of ]131I]CT occurred rapidly in the presence of 50--200 mg porcine thyroid tissues; however, little or no hormone deiodination was observed. Porcine liver, kidney and lung slices also degraded [131I]CT. The data indicate that a nonspecific proteolytic enzyme, capable of rapid CT degradation, is liberated from thyroid tissue slices in vitro. This substance, which is found in the cytosol fraction of thyroid tissue, is heat labile, has a molecular weight between 25,000 and 100,000, displays an acidic pH maximum for CT degradation and is inhibited by sulfhydryl enzyme inhibitors. The liberation of this substance from thyroid slices may explain the relative unresponsiveness of CT secretion observed in previous in vitro studies.
Mol Cell Endocrinol 1978 Oct
PMID:Characteristics of calcitonin degradation in vitro produced by incubation with procine thyroid tissue. 72 Jul 48

1. Plasma levels of immunoreactive calcitonin were measured in 22 patients with untreated Paget's disease of bone and in 22 control subjects matched for age and sex. 2. No significant differences in plasma calcitonin were found between patients and control subjects, and hormone levels did not correlate significantly with activity of plasma alkaline phosphatase. 3. These results suggest that Paget's disease of bone is not due to deficient of endogenous calcitonin.
Clin Sci Mol Med 1977 Mar
PMID:Plasma calcitonin in Paget's disease of bone. 84 63

1. Foetal rat hemi-calvaria were incubated in organ culture with sera from patients with active rheumatoid arthritis. 2. Increased 45Ca resorption was produced by sera from patients who were hypercalcaemic. 3. This bone-resorbing effect could be inhibited by calcitonin.
Clin Sci Mol Med 1976 Aug
PMID:Bone-resorbing activity in the sera of patients with rheumatoid arthritis. 95 67

1. The effect of calcitonin, a large amount of calcium given orally, pentagastrin and glucagon on plasma 47Ca radioactivity curves in subjects pretreated with 47Ca was examined. 2. A sudden increase of plasma radioactivity after intravenous administration of calcitonin and pentagastrin and after the oral calcium load was observed in normal subjects; the intravenous infusion of glucagon was less effective. 3. Two thyroparathyroidectomized patients who responded to the calcitonin infusion did not respond to the oral calcium load. 4. These data may be considered to offer indirect evidence of endogenous calcitonin secretion in man.
Clin Sci Mol Med 1976 Sep
PMID:Indirect evidence of calcitonin secretion in man. 98 25

1. Twelve patients with symptomatic Paget's disease were studied before starting treatment with salmon calcitonin (12-5 mug) subcutaneously twice daily. Eleven of them were studied again after 3 months on this therapy. 2. Although pretreatment values for urinary total hydroxyproline excretion and cardiac output were considerably increased in some patients, there was no correlation between these two variables in the group as a whole. 3. Treatment resulted in a striking reduction in disease activity; the mean urinary hydroxyproline decreased 67%. 4. There was, however, no significant fall in cardiac output or change in oxygen transport during treatment. 5. Of the eight patients with bone pain who received treatment, five claimed complete pain relief.
Clin Sci Mol Med Suppl 1975 Jun
PMID:Effect of salmon calcitonin on cardiac output, oxygen transport and bone turnover in patients with Paget's disease. 105 85


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