BIOASSAY OF PARATHYROID HORMONE IN RATS BY DETERMINATION OF PLASMA CALCIUM, URINARY 32P EXCRETION AND SERUM ALKALINE PHOSPHATASE

1966 ◽  
Vol 35 (3) ◽  
pp. 229-238 ◽  
Author(s):  
R. J. TREACHER
Keyword(s):  
Alkaline Phosphatase ◽  
Parathyroid Hormone ◽  
Serum Calcium ◽  
Calcium Concentration ◽  
Serum Alkaline Phosphatase ◽  
Plasma Calcium ◽  
Significant Alteration ◽  
Good Precision ◽  
Serum Calcium Concentration

SUMMARY Methods for assay of parathyroid hormone based on an increase in serum calcium concentration, urinary 32P excretion and serum alkaline phosphatase elevation in parathyroidectomized rats have been compared and modifications introduced to improve sensitivity, precision, speed and ease of manipulation. Both the serum calcium and urinary 32P assay gave good precision (mean λ = 0·23 and 0·29, respectively) but by the serum calcium method less than 10 USP units of parathyroid hormone could not be detected, whereas the phosphaturic assay detects as little as 0·5 USP unit. Both assays are simple to perform and each requires only 2 days to complete. They can be combined in a single design using the same animals. Assays based on serum alkaline phosphatase levels in parathyroidectomized rats were not successful since it was impossible to produce a significant alteration in serum alkaline phosphatase by the administration of parathyroid hormone.

scholarly journals Effect of the first and second postpartum partial milking on blood serum calcium concentration in dairy cows

2014 ◽  
Vol 59 (No. 3) ◽  
pp. 128-133
Author(s):  
E.G. Salgado-Hernández ◽  
A. Aparicio-Cecilio ◽  
F.H. Velásquez-Forero ◽  
D.A. Castillo-Mata
Keyword(s):  
Blood Serum ◽  
Dairy Cows ◽  
Serum Calcium ◽  
Metabolic Disorders ◽  
Calcium Concentration ◽  
Atomic Absorption Spectrophotometry ◽  
Serum Calcium Concentration ◽  
Group 2 ◽  
Group 1

Parturient paresis and subclinical hypocalcemia are frequent metabolic disorders in dairy cows postpartum. The aim of this study was to determine the effect of postpartum partial milking in the first two milkings on blood serum calcium concentration in dairy cows. Twenty multiparous Holstein dairy cows were randomized into two groups. Cows of group 1 (n = 10) were partially milked at the first and second milking postpartum. Cows of group 2 (n = 10) were completely milked. Blood samples were collected from all animals 5–7 days before calving, within 30 min after calving, and 4, 8, 12, 16, 20, 24, 28, and 32 h after calving for determination of serum calcium (Ca), phosphorus (P), and magnesium (Mg) concentrations. Colostrum production was registered and sampled in the first and second milking. Concentration of Ca in colostrum was determined by atomic absorption spectrophotometry. Serum Ca and P concentrations decreased in both groups after parturition (P < 0.05) and remained low during 32 h postpartum with no difference observed between groups (P > 0.05). Serum concentrations of Mg were stable in all samples and no statistical difference was observed between groups (P > 0.05). Colostrum production was higher in completely milked cows only in the first postpartum milking (P < 0.05), but there was no difference between groups at the second milking. Total Ca secretion in colostrum was higher in the complete milking group at the first and second postpartum milking. Colostrum Ca secretion increased at the second milking with respect to the first one in both groups (P < 0.05). There was no correlation between serum Ca and colostrum Ca (P > 0.05). In this study, the partial milking of colostrum in the first and second milking postpartum did not prevent subclinical hypocalcemia in dairy cows.  

scholarly journals Persistent Hypercalcemia After Parathyroidectomy in an Adolescent and Effect of Treatment With Cinacalcet HCl

2006 ◽  
Vol 52 (12) ◽  
pp. 2286-2293 ◽  
Author(s):  
Lorin M Henrich ◽  
Alan D Rogol ◽  
Pierre D’Amour ◽  
Michael A Levine ◽  
John B Hanks ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Primary Hyperparathyroidism ◽  
Serum Calcium ◽  
Calcium Concentration ◽  
Case Conference ◽  
Serum Calcium Concentration ◽  
Pharmacodynamic Profile ◽  
Laboratory Results ◽  
Calcium Phosphorus ◽  
Effect Of Treatment

Abstract Background: Hyperparathyroidism is uncommon in adolescence and is more likely to persist after parathyroidectomy than in adults. Cinacalcet HCl is a new calcimimetic that has been used successfully for the treatment of primary and secondary hyperparathyroidism in adults, but its use in adolescents has not been reported. Case: A 16 year-old male presented with hypercalcemia that had persisted for 1.5 years after parathyroidectomy for primary hyperparathyroidism. Parathyroid hormone (PTH) concentrations were nonsupressed despite a mean (SD) serum calcium concentration of 2.82 (0.06) mmol/L. Treatment with cinacalcet HCl was initiated and a pharmacodynamic profile was obtained for serum calcium, phosphorus, and PTH. Cinacalcet HCl normalized serum calcium. The changes in PTH were assay dependent. Issues: We use this case conference to review the evaluation of hypercalcemia in adolescents, examine the changes in relevant laboratory results during treatment with cinacalcet HCl, and discuss differences among assays for PTH. Conclusions: Interpretation of PTH results in patients treated with cinacalcet HCl requires consideration of the pharmacodynamic effects of the drug and the nature of the PTH assay.

Radioimmunoassay of parathyroid hormone (parathyrin) in monkey and man.

1977 ◽  
Vol 23 (11) ◽  
pp. 1989-1994 ◽  
Author(s):  
G K Hargis ◽  
G A Williams ◽  
W A Reynolds ◽  
W Kawahara ◽  
B Jackson ◽  
...  
Keyword(s):  
Tissue Culture ◽  
Parathyroid Hormone ◽  
Rhesus Monkey ◽  
Serum Calcium ◽  
Calcium Concentration ◽  
Culture Media ◽  
Parathyroid Tissue ◽  
Serum Calcium Concentration ◽  
Tissue Culture Media

Abstract A radioimmunoassay for rhesus monkey and human immunoreactive parathyrin was developed in which a selected anti-bovine parathyrin antiserum, radioiodinated purified bovine parathyrin tracer, and human parathyroid tissue-culture media standards were used. The resulting data indicate that (a) the method is sensitive, specific, accurate and reproducible; (b) it is valid for both the rhesus monkey and the human; (c) the serum immunoreactive parathyrin concentration of the monkey is essentially the same as that in man; (d) monkey immunoreactive parathyrin responds to changes in serum calcium concentration similarly to that in man; and (e) the rhesus monkey is therefore a suitable species in which to study parathyroid physiology, from which conclusions can be applied to the human.

Effects of acute metabolic acidosis on parathyroid hormone action and calcium mobilization

1976 ◽  
Vol 230 (1) ◽  
pp. 127-131 ◽  
Author(s):  
N Beck ◽  
SK Webster
Keyword(s):  
Parathyroid Hormone ◽  
Metabolic Acidosis ◽  
Serum Calcium ◽  
Calcium Concentration ◽  
Tubular Reabsorption ◽  
Calcium Mobilization ◽  
Measurable Effect ◽  
Bilateral Nephrectomy ◽  
Serum Calcium Concentration ◽  
Acute Metabolic Acidosis

Mechanisms through which metabolic acidosis increases calcium mobilization have been investigated in thyroparathyroidectomized rats with induction of acute metabolic acidosis by infusing NH4C1 intravenously. Acute metabolic acidosis directly raised serum calcium concentration and augmented the effect of parathyroid hormone (PTH) to raise serum calcium concentration. The same effects of metabolic acidosis were observed in rats with surgically removed intestines and bilateral nephrectomy, suggesting that acute metabolic acidosis directly increases calcium mobilization from bone and augments the effect of PTH to mobilize calcium from bone. In the kidney, acidosis directly inhibited the tubular reabsorption of calcium, but augmented the effect of PTH to increase tubular reabsorption of calcium. Acidosis had no measurable effect on calcitonin action.

Hypo-Hyperparathyroidism: Evidence for a Defective Parathyroid Hormone

PEDIATRICS ◽  
1977 ◽  
Vol 60 (3) ◽  
pp. 343-348
Author(s):  
Matthew H. Connors ◽  
Julian J. Irias ◽  
Mahin Golabi
Keyword(s):  
Alkaline Phosphatase ◽  
Parathyroid Hormone ◽  
Bone Resorption ◽  
Phosphatase Activity ◽  
Serum Calcium ◽  
Alkaline Phosphatase Activity ◽  
Hormone Level ◽  
Serum Alkaline Phosphatase ◽  
Parathyroid Hormone Level ◽  
Parathyroid Extract

Biochemical evidence for hypoparathyroidism and roentgenographic evidence for hyperparathyroidism were present in a 7-year-old girl with seizures and tetany. She was hypocalcemic (4.7 mg/dl), hyperphosphatemic (11 mg/dl), and normomagnesemic, with elevated parathyroid hormone level (2,603 pg/dl and 3,693 pg/dl in immunoassays utilizing two different antisera). Somatic features of pseudohypoparathyroidism were absent. Increased serum alkaline phosphatase activity (335 IU/liter) with evidence of subperiosteal bone resorption suggested parathyroid hormone activity on bone. Intramuscular administration of parathyroid extract caused a rise in serum calcium level (9.6 mg/dl) and a fall in serum phosphorus level (7.9 mg/dl). The serum calcium, phosphorus, and alkaline phosphatase activity became normal during vitamin D therapy. Parathyroid hormone values and bone roentgenograms became normal. With serum calcium and phosphorus levels normal, ethylenediaminetetraacetic acid infusion was followed by an increase in plasma parathyroid hormone level but not in urinary cyclic adenosine monophosphate (AMP) or phosphaturia; in contrast, parathyroid extract induced cyclic AMP excretion and phosphaturia. These results suggest that endogenous parathyroid hormone in this patient affects bone resorption but not renal handling of phosphate. We infer that this represents a defective endogenous parathyroid hormone.

Parathyroid Hormone Secretion and Serum Calcium Concentration - A Deterministic View of its Regulation

1995 ◽  
Vol 27 (05) ◽  
pp. 244-250
Author(s):  
E. Heidbreder ◽  
H. Naujoks ◽  
U. Brosa ◽  
L. Schramm ◽  
R. Götz
Keyword(s):  
Parathyroid Hormone ◽  
Serum Calcium ◽  
Calcium Concentration ◽  
Hormone Secretion ◽  
Serum Calcium Concentration
Sign in / Sign up

Export Citation Format

Share Document