Third international standard for posterior pituitary; re-named third international standard for oxytocic, vasopressor and antidiuretic substances in 1956.

摘要: Abstract In October 1955, stocks of the Second International Standard for Posterior Pituitary were running low and Department Biological Standards National Institute Medical Research, London, was asked to proceed with arrangements an international collaborative assay material Third Standard. A single 142-g batch posterior-pituitary-lobe powder obtained distributed in ampoules, approximately 30-mg quantities. Samples sent 19 laboratories 10 countries. In all, 185 assays carried out, 122 oxytocic activity, 53 vasopressor activity antidiuretic activity. On basis results, which analysed statistically at it agreed that potency (re-named Oxytocic, Vasopressor Antidiuretic Substances 1956, view recent synthesis oxytocin vasopressin) should be expressed as 2.0 Units per milligram. The Unit therefore remains unchanged 0.5 mg dry powder.