A plasma calcium assay for parathyroid hormone, using parathyroidectomized rats

A mouse urine phosphate assay for parathyroid hormone, with certain applications

“…Using corrected responses the average limits of error were 60-168%. These are slightly wider than those reported by Bliss & Rose (1940) for the dog serum calcium assay (79-126%) and very similar to those obtained in the parathyroidectomized rat plasma calcium assay (64-158%) (Davies et al 1954).…”

“…Comparison of the ratio of renal phosphate activity/plasma calcium activity in various types of parathyroid extracts Using Parathormone as the standard hormone, both a mouse urine phosphate assay and a parathyroidectomized rat plasma calcium assay (Davies et al 1954) were carried out on a hydrochloric acid preparation of ox parathyroid gland prepared according to Collip & Clark (1925b) and on an acetone-HCl preparation made according to L'Heureux et al (1947) in order that the ratio of renal phosphate activity/plasma calcium activity might be calculated. Parathormone is standardized before issue and its calcium activity is 100 U.S.P.…”

“…As shown in Table 6, the accuracy of the mouse assay method based on H is comparable with, though slightly less good, than that of the dog plasma calcium assay (Collip & Clark, 1925 a;Bliss & Rose, 1940), and rather similar to that of the parathyroidectomized rat plasma calcium assay (Davies et al 1954). Our figures suggest that, if dose levels of an extract being tested were such as to give a potency of 1.0, the use of about twice as many cages of mice as are specified in the present assay (i.e.…”

“…In assays III and IV this value of t was significant when mg P/ml. was used, and in all except assay V the value of t was reduced by the use of H. (Davies et al 1954) were carried out on a hydrochloric acid preparation of ox parathyroid gland prepared according to Collip & Clark (1925b) and on an acetoneHCl preparation made according to L'Heureux et al (1947) U.S.P. units.…”

“…Since the slopes for the volume-response regression lines varied with different doses it was possible neither to eliminate the effect of varying volume by the use of co-variance nor to use some simple correction as in the parathyroidectomized rat plasma calcium assay (Davies et al 1954), as this type of adjustment is also based on a common slope.…”