ASSAY OF PARATHYROID HORMONE IN HUMAN URINE USING 32P EXCRETION IN PARATHYROIDECTOMIZED RATS

Parathyroid hormone was extracted from human urine by benzoic acid adsorption and assayed by measuring 32P excretion in parathyroidectomized rats. Values of λ averaged 0.30 in 9 observations and the recovery rate of the extraction procedure was 75, 48, and 51 %. In 3 of 5 normal subjects the amount of parathyroid hormone in 24 hour urine ranged between 10–30 USP units, while in others it was undetectable. In 6 of 7 untreated cases of hyperthyroidism, values above 30 were obtained. After treatment, the elevated values showed a tendency to return to the normal level. Elevated values were also observed in 1 case of hyperparathyroidism, 3 cases of hypertension, and 1 case of nephrolithiasis. In 2 cases of postoperative hypoparathyroidism with manifestations of tetany, parathyroid hormone was undetectable in the urine. In 17 miscellaneous cases urinary parathyroid hormone was undetectable in 7, and ranged between 6 and 30 USP units in others.