Loss of Immunoreactivity of Human Serum Parathyroid Hormone by the Action of Rat Kidney Enzyme, Preferentially Hydrolyzing Parathyroid Hormone

A study was made of the enzymic degradation of 125I-labelled parathyroid hormone by rat kidney microsomes. Incubation with microsomes resulted in rapid destruction of the labelled hormone. The microsomal factor was not separable by dialysis, and the reaction was favoured by pH values in the physiological range. Velocity of the reaction varied directly as the substrate concentration, and additional crude parathyroid hormone (trichloroacetic acid-precipitated, 3·68mg./ml.) inhibited destruction of labelled hormone. There was much less inhibition with added trichloroacetic acid-precipitated calcitonin (3·92mg./ml.) and virtually none with added pig insulin (3·80mg./ml.). Gel filtration of control medium on P6 (Bio-Gel) yielded one radioactive peak at the void volume. After incubation with microsomes three further peaks were obtained on gel filtration. Only the void-volume peak contained intact 125I-labelled parathyroid hormone, indicating that the microsomal enzyme degraded labelled hormone to a number of smaller fragments.

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Parathyroid Hormone Assay in Primary Hyperparathyroidism: Experiences with a Radioimmunoassay Based on Commercially Available Reagents

Clinical Chemistry ◽

10.1093/clinchem/20.3.369 ◽

1974 ◽

Vol 20 (3) ◽

pp. 369-375 ◽

Cited By ~ 50

Author(s):

M Kleerekoper ◽

J P Ingham ◽

S W McCarthy ◽

S Posen

Keyword(s):

Parathyroid Hormone ◽

Primary Hyperparathyroidism ◽

Human Serum ◽

Serum Calcium ◽

Parathyroid Tissue ◽

Normal Range ◽

Serum Parathyroid Hormone ◽

Skeletal Changes ◽

Parathyroid Hormone Assay ◽

Positive Correlations

Abstract A radioimmunoassay is described for parathyroid hormone in human serum, in which commercially available reagents are used almost exclusively. This assay can be done by any laboratory with experience in radloimmunoassay. Thirty-two of thirty-three patients with surgically proven primary hyperparathyroidism had detectable concentrations of parathyroid hormone in their serum, and concentrations of the hormone exceeded the normal range in 24 of them. Significant positive correlations were found between pre-operative serum calcium, pre-operative serum parathyroid hormone, and the weight of parathyroid tissue removed at operation. These three parameters were also significantly correlated with severity of the skeletal changes as assessed by semiquantitative histological methods.

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Interaction between parathyroid hormone and prostaglandin E1 on cyclic AMP metabolism in rat kidney

Acta Endocrinologica ◽

10.1530/acta.0.0930339 ◽

1980 ◽

Vol 93 (3) ◽

pp. 339-345 ◽

Cited By ~ 2

Author(s):

Naokazu Nagata ◽

Yuriko Ono ◽

Narimichi Kimura

Keyword(s):

Parathyroid Hormone ◽

Cyclic Amp ◽

Adenylate Cyclase ◽

Rat Kidney ◽

Prostaglandin E ◽

Cortical Tissue ◽

Newborn Rat ◽

Simultaneous Addition ◽

Renal Cortical Tissue ◽

Subsequent Addition

Abstract. The interaction between parathyroid hormone (PTH) and prostaglandin E1 (PGE1) in influencing cyclic AMP metabolism in rat renal cortical tissue was examined. PTH and PGE1 stimulated additively the adenylate cyclase activity in the homogenate of the tissue. Both PTH and PGE1 enhanced the level of cyclic AMP in the incubated renal cortical tissue, but the effect of their simultaneous addition did not exceed the effect induced by PTH alone. Cyclic AMP accumulated in the incubation medium by stimulation by PTH was decreased by the simultaneous addition of PGE1. When the tissue was pre-incubated for 30 min with 2 to 10 μg/ml of PGE1, the magnitude of the increase of cyclic AMP caused by PTH subsequently added was lessened. However, the response to PTH of adenylate cyclase preparation obtained from the homogenate of PGE1-pre-treated tissue was not decreased. When first PTH was added to the incubating renal cortical tissue, the subsequent addition of PGE1 accelerated the decrease of cyclic AMP content in the tissue and decreased the amount of cyclic AMP released from the tissue. The interaction of PTH and PGE1 on cyclic AMP metabolism in the renal cortical tissue was in contrast to that seen in newborn rat calvaria where PGE1 and PTH acted additively in enhancing the level of cyclic AMP.

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Evaluation of intact serum parathyroid hormone (PTH 1-84) in the diagnosis of disorders of calcium metabolism

Acta Endocrinologica ◽

10.1530/acta.0.117s064 ◽

1988 ◽

Vol 117 (4_Suppl) ◽

pp. S64-S65

Author(s):

K. KRUSE ◽

U. KRACHT ◽

K. WOHLFART ◽

U. KRUSE

Keyword(s):

Parathyroid Hormone ◽

Calcium Metabolism ◽

Serum Parathyroid Hormone

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Faculty Opinions recommendation of Serum parathyroid hormone is associated with increased cortical porosity of the inner transitional zone at the proximal femur in postmenopausal women: the Tromsø Study.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732115833.793580278 ◽

2020 ◽

Author(s):

Rebecca Mason

Keyword(s):

Parathyroid Hormone ◽

Postmenopausal Women ◽

Proximal Femur ◽

Transitional Zone ◽

Cortical Porosity ◽

Serum Parathyroid Hormone

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Low serum parathyroid hormone is a risk factor for peritonitis episodes in incident peritoneal dialysis patients: a retrospective study

BMC Nephrology ◽

10.1186/s12882-021-02241-0 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Yuqi Yang ◽

Jingjing Da ◽

Yi Jiang ◽

Jing Yuan ◽

Yan Zha

Keyword(s):

Risk Factor ◽

Peritoneal Dialysis ◽

Parathyroid Hormone ◽

Proportional Hazard ◽

Serum Parathyroid Hormone ◽

Cox Proportional Hazard ◽

Cox Proportional Hazard Regression ◽

Gram Negative Organisms ◽

Serum Pth

Abstract Background Serum parathyroid hormone (PTH) levels have been reported to be associated with infectious mortality in peritoneal dialysis (PD) patients. Peritonitis is the most common and fatal infectious complication, resulting in technique failure, hospital admission and mortality. Whether PTH is associated with peritonitis episodes remains unclear. Methods We examined the association of PTH levels and peritonitis incidence in a 7-year cohort of 270 incident PD patients who were maintained on dialysis between January 2012 and December 2018 using Cox proportional hazard regression analyses. Patients were categorized into three groups by serum PTH levels as follows: low-PTH group, PTH < 150 pg/mL; middle-PTH group, PTH 150-300 pg/mL; high-PTH group, PTH > 300 pg/mL. Results During a median follow-up of 29.5 (interquartile range 16–49) months, the incidence rate of peritonitis was 0.10 episodes per patient-year. Gram-positive organisms were the most common causative microorganisms (36.2%), and higher percentage of Gram-negative organisms was noted in patients with low PTH levels. Low PTH levels were associated with older age, higher eGFR, higher hemoglobin, calcium levels and lower phosphate, alkaline phosphatase levels. After multivariate adjustment, lower PTH levels were identified as an independent risk factor for peritonitis episodes [hazard ratio 1.643, 95% confidence interval 1.014–2.663, P = 0.044]. Conclusions Low PTH levels are independently associated with peritonitis in incident PD patients.

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The effect of parathyroid hormone on adenyl cyclase in rat kidney

Biochimica et Biophysica Acta (BBA) - General Subjects ◽

10.1016/0304-4165(68)90309-7 ◽

1968 ◽

Vol 158 (3) ◽

pp. 484-486 ◽

Cited By ~ 38

Author(s):

Tomáš Douša ◽

Ivan Rychlík

Keyword(s):

Parathyroid Hormone ◽

Rat Kidney ◽

Adenyl Cyclase

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A radioimmunoassay for human parathyroid hormone utilizing a goat anti-bovine PTH serum

Acta Endocrinologica ◽

10.1530/acta.0.0960215 ◽

1981 ◽

Vol 96 (2) ◽

pp. 215-221 ◽

Cited By ~ 8

Author(s):

L. E. Mallette

Keyword(s):

Parathyroid Hormone ◽

Primary Hyperparathyroidism ◽

Secondary Hyperparathyroidism ◽

Human Serum ◽

Central Region ◽

Antigenic Site ◽

Human Parathyroid Hormone ◽

Domestic Goat ◽

Standard Serum ◽

Dilution Curves

Abstract. An antiserum (NG-1) against bovine PTH (bPTH) generated in the domestic goat was characterized for use in the radioimmunoassay of PTH in human serum. When a carboxyterminal fragment of bPTH is used as radioligand, this antiserum detects only an antigenic site in the central region of the hPTH molecule. The synthetic hormone fragment, hPTH-(44-68), will displace 93% of the tracer, after which the addition of intact hPTH causes no further displacement. The assay does not detect the synthetic aminoterminal 1-34 fragment of the bovine or human hormones, nor the carboxyterminal fragment of the human hormone, hPTh-(53-84). Standard curves with bPTH-(1-84) and partially purified hPTH are not parallel, so that hPTH is used as standard. Serum from subjects with uraemia or primary hyperparathyroidism gives dilution curves parallel to that with the hPTH standard. The assay with NG-1 has been applied to the diagnosis of primary and secondary hyperparathyroidism, used to monitor the disappearance of PTH after parathyroidectomy, and for measurement of PTH in selective venous samples.

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Purification and properties of 2-aminoadipate: 2-oxoglutarate aminotransferase from bovine kidney

Biochemical Journal ◽

10.1042/bj2610761 ◽

1989 ◽

Vol 261 (3) ◽

pp. 761-768 ◽

Cited By ~ 13

Author(s):

D R Deshmukh ◽

S M Mungre

Keyword(s):

Rat Kidney ◽

Deae Cellulose ◽

Dicarboxylic Acids ◽

Structural Similarity ◽

Appreciable Amount ◽

Kinetic Properties ◽

Bovine Kidney ◽

Purification And Properties ◽

Kidney Enzyme ◽

Structural Differences

Previous studies with rat kidney preparations indicated that 2-aminoadipate aminotransferase (AadAT) and kynurenine aminotransferase (KAT) activities are properties of a single protein. We found that bovine kidney contains an appreciable amount of AadAT activity, but lacks KAT activity. AadAT from bovine and rat kidney extracts were purified to electrophoretic homogeneity. The purification procedure included fractionation with (NH1)2SO1, heat treatment, DEAE-cellulose chromatography and hydroxyapatite chromatography. Physical and kinetic properties, such as pH optima, Km for substrates, Mr, electrophoretic mobility and inhibition by dicarboxylic acids of bovine kidney AadAT, were similar to those of the rat kidney enzyme. However, bovine kidney AadAT differed from rat kidney AadAT in substrate specificity, amino acid composition and stability when stored. The titration curve of bovine kidney AadAT was also different from that of the rat kidney enzyme. The results suggest that bovine kidney AadAT may have some structural similarity to rat kidney AadAT and that the structural differences observed between the two enzymes may explain the absence of KAT activity in bovine kidney.

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