Effect of One Haemodialysis Treatment on the Plasma Concentrations of Intact Parathyroid Hormone and Ionised Calcium: Usefulness of End-dialysis Values in Evaluating the Suppressibility of Hyperparathyroidism

Background: We investigated whether increased protease activity explains the increased in vitro degradation of intact parathyroid hormone (iPTH) observed in serum when compared to EDTA plasma. Methods: Pre-dialysis blood samples for iPTH were taken from 11 patients with chronic renal failure and collected into plain glass tubes, tubes containing 200 KIU/mL aprotinin (a protease inhibitor) and EDTA tubes. All sample aliquots were separated at 20 min, 1 h, 2 h, 4 h, 8 h and 24 h post collection. Results: Over 24 h, iPTH concentrations remained unchanged in EDTA tubes. iPTH concentrations were significantly lower in both plain tubes ( P < 0·01) and aprotinin tubes ( P < 0·001) at 24 h when compared to the baseline sample (20 min). At 24 h, iPTH concentrations in EDTA tubes were higher than in plain tubes ( P < 0·001) and aprotinin tubes ( P < 0·01). The addition of aprotinin to plain tubes significantly reduced the degradation of iPTH ( P < 0·05) at 24 h. Conclusion: Aprotinin significantly reduces the in vitro degradation of iPTH in plain tubes at 24 h from 24·7% to 9·6%. We suggest that increased protease activity contributes to the decline in serum iPTH over time. As this is observed in serum and not plasma it suggests that the increased protease activity may be due to the clotting process.

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Serum intact parathyroid hormone levels in cats with chronic kidney disease

Pesquisa Veterinária Brasileira ◽

10.1590/s0100-736x2013000200015 ◽

2013 ◽

Vol 33 (2) ◽

pp. 229-235 ◽

Cited By ~ 4

Author(s):

Luciano H. Giovaninni ◽

Marcia M. Kogika ◽

Marcio D. Lustoza ◽

Archivaldo Reche Junior ◽

Vera A.B.F. Wirthl ◽

...

Keyword(s):

Chronic Kidney Disease ◽

Parathyroid Hormone ◽

Kidney Disease ◽

Stage Iv ◽

Control Group ◽

Intact Parathyroid Hormone ◽

Acid Base ◽

Acid Base Status ◽

Serum Ionized Calcium ◽

Progression Of Renal Disease

Chronic kidney disease (CKD) is frequently observed in cats and it is characterized as a multisystemic illness, caused by several underlying metabolic changes, and secondary renal hyperparathyroidism (SRHPT) is relatively common; usually it is associated with the progression of renal disease and poor prognosis. This study aimed at determining the frequency of SRHPT, and discussing possible mechanisms that could contribute to the development of SRHPT in cats at different stages of CKD through the evaluation of calcium and phosphorus metabolism, as well as acid-base status. Forty owned cats with CKD were included and divided into three groups, according to the stages of the disease, classified according to the International Renal Interest Society (IRIS) as Stage II (n=12), Stage III (n=22) and Stage IV (n=6). Control group was composed of 21 clinically healthy cats. Increased serum intact parathyroid hormone (iPTH) concentrations were observed in most CKD cats in all stages, and mainly in Stage IV, which hyperphosphatemia and ionized hypocalcemia were detected and associated to the cause for the development of SRHPT. In Stages II and III, however, ionized hypercalcemia was noticed suggesting that the development of SRHPT might be associated with other factors, and metabolic acidosis could be involved to the increase of serum ionized calcium. Therefore, causes for the development of SRHPT seem to be multifactorial and they must be further investigated, mainly in the early stages of CKD in cats, as hyperphosphatemia and ionized hypocalcemia could not be the only factors involved.

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Intact parathyroid hormone levels and primary hyperparathyroidism

Endocrine Research ◽

10.1080/07435800.2017.1292528 ◽

2017 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Haidar Al-Hraishawi ◽

Peter J. Dellatore ◽

Xinjiang Cai ◽

Xiangbing Wang

Keyword(s):

Parathyroid Hormone ◽

Primary Hyperparathyroidism ◽

Intact Parathyroid Hormone ◽

Hormone Levels

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Comparison of the feedback effect of magnesium and calcium on parathyroid hormone secretion in man

Journal of Endocrinology ◽

10.1677/joe.0.1130117 ◽

1987 ◽

Vol 113 (1) ◽

pp. 117-122 ◽

Cited By ~ 31

Author(s):

O. Ferment ◽

P. E. Garnier ◽

Y. Touitou

Keyword(s):

Parathyroid Hormone ◽

Urinary Excretion ◽

Hormone Secretion ◽

Plasma Concentrations ◽

Magnesium Salt ◽

Saline Injection ◽

Molar Basis ◽

Magnesium Salts ◽

High Doses

ABSTRACT Administration of high doses of magnesium is known to produce a decrease in parathyroid hormone (PTH) secretion in human patients but the effect of magnesium on the secretion of PTH in healthy man is not known. We have looked at the effect of a relatively moderate i.v. dose of magnesium (7·08 mmol) in seven healthy men. In addition and for comparison the effect of calcium (4·25 mmol) was studied. Two magnesium salts were considered, magnesium sulphate (MgSO4) and magnesium pyrrolidone carboxylate (MgPC). Four i.v. injections were given at 08.00 h (MgPC, NaCl (control), MgSO4 and Ca gluconate), with an interval of 1 week between each injection. Whatever the magnesium salt the variations in plasma concentrations of magnesium were the same whereas no change in erythrocyte magnesium was observed. Plasma concentration of C-terminal PTH did not show significant variations after MgPC or saline injection. Both MgSO4 and Ca gluconate produced a statistically significant 30% decrease in plasma PTH levels 45 min after the injection. The effect was more sustained with calcium (2 h) than with magnesium (45 min). The urinary excretion of magnesium was significantly higher after injection of MgSO4 than after MgPC. These results suggest (1) that magnesium was, on a molar basis, less potent than calcium in regulating PTH secretion in vivo, (2) that the nature of the magnesium salt used must be kept in mind for the interpretation of the effect of magnesium on PTH secretion in vivo and (3) that the decrease in plasma PTH can partly explain the larger urinary excretion of magnesium after MgSO4 than after MgPC. J. Endocr. (1987) 113, 117–122

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