The Assay of Small Amounts of Antidiuretic Activity by Intravenous Injections Into Mice

Abstract

Antidiuretic activity has been assayed by intravenous injection of the test fluid into unanaesthetized mice to which three doses of water had been given by stomach tube. The method seems to be suitable for doses of the approximate range of 10 to 50 \g=m\U.vasopressin 10 g./ body weight.

The degree of inactivation of the antidiuretic activity of vasopressin by the kidneys and the liver of rats

“…He claimed that vasopressin is completely destroyed by liver homogenates. His technique of estimation, however, does not fully warrant such a conclusion, as the sensitivitv of the method he used is only 2-0 mU vasopressin/100 g body weight (Burn, 1931;Heller & Blackmore, 1952). The method used in the present investigation has a sensitivity of 5 ,uU vasopressin/100 g (Dicker, 1953).…”

A method for the assay of very small amounts of antidiuretic activity with a note on the antidiuretic titre of rats' blood

“…Ordinate: values for a. Abscissa: log doses of vasopressin (,uU/100 g). Note that there was no differential effect between 3 and 3 5 ,U/100 g and between 50 and 60 ,U/100 g. Woods, 1934;Heller & Blackmore, 1952). This could be explained if the greater dilution of body fluids produced a more complete suppression of the level of endogenous posterior pituitary antidiuretic hormones.…”

“…The most sensitive ofthe published tests (see Table 1) for estimating antidiuretic activity are those of Jeffers, Livezey & Austin (1942) on the anaesthetized rat, and of Heller & Blackmore (1952) on the non-anaesthetized mouse. The sensitivity of the rat preparation was 20 ,U/rat, that of the mouse about 10-50 uU/10 g. Both these groups of observers estimated the antidiuretic activity while the water load was declining and the blood concentration was correspondingly increasing.…”

A New Method of Bioassay for Antidiuretic Substance and Antidiuretic Activity of the Plasma in the Normal Subjects

“…The methods (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), which have been proposed for the assay of the anti diuretic hormone (ADH) of the neurohypophysis, are summarized in Table 3 with special reference to the urine collection and the administration of the test material.…”