Application of newly synthesized 1-34 human parathyroid hormone for diagnostic tests

1-34 human parathyroid hormone (1-34 hPTH) was synthesized by a liquid-phase method and prepared for clinical use (specific activity, 3281 U/mg). With this preparation, the toxicity was studied in 22 normal volunteers and the metabolic effects in 15 individuals. Intradermal administration of 4 ng of 1-34 hPTH caused neither abnormal local skin reactions nor toxicity in terms of subjective and objective parameters. When administered intravenously at doses of from 2 to 20 microgram as a bolus, the preparation caused no acute or subacute toxicity judging from the results of various clinical and laboratory studies, except for transient mild hypotension and headache in a minority of subjects. For diagnostic use, 20 microgram of 1-34 hPTH administered intravenously was found to produce effects almost equivalent to those of 200 USPU U of Parathormone (PTE, Eli Lilly). Thus, the criteria for differentiation of hypoparathyroidism from pseudo-hypoparathyroidism devised with 2000 USP U of PTE as a test substance was found to be applicable when 20 microgram of 1-34 hPTH was utilized.