Improvements in the accuracy of insulin assay on white mice. I¹

Abstract

According to previous publications from this laboratory ( H e mm i n g s e n , 1933, p. 198 and 208; H e m m i n g s e n and Weitze, 1936, p. 628), the accuracy to be obtained in single insulin assays involving abt. 100-160 mice with a body weight dispersion of 4 g, corresponded to a standard deviation varying from abt. I 2 to abt. 25 p. c. of the average.Unsuccessful attemps at improving the accuracy of the convulsive dose method have been published for tiny fishes ( H e m m i n gs e n and B r u u n , 1938) and adrenalectomized rats and mice ( H e mm i n g s e n , N i e l s e n and L e v i n N i e l s e n , 1938).As reported by H e m m i n g s e n and M a r k s (1933, p. 88-89) the mortality of mice during the experiment and on the day following the experiment is I 9. I p. c. when the tests are carried out at 37O C against I 2.4 p. c. when they are carried out at 290 C. According to K r o g h and H e m m i n g s e n ( 1 9 2 6 ) and T e t e n s N i e l s e n (1938) it is possible to observe marked symptoms of the injected insulin also at somewhat lower temperatures; and they state that the reduction of body temperature and the resulting lower metabolic activity protects the mice against the lethal effects of insulin.Experiments at lower temperatures might thus be expected to entail a smaller rate of mortality. In addition, an experimental temperature nearer to the environmental temperature obtaining between the experiments might tend to protect the mice against catching colds, which often disturb experiments at 29" C and are probably largely responsible for the high mortality.

An Immunochemical Assay of Total Extractable Insulin in Man *

“…Prior to immunological assay, the stock extracts were diluted 500-fold with the glycine albumin buffer. The biological activity of these extracts was also determined by the mouse convulsion assay (19 protein. The latter was eventually discarded when it proved too soluble in sodium sulfite at the pH of 8.5 used for the assay.…”

Modeling Ordered Choices: A Primer and Recent Developments

“…But, this was the first point at which the technique was formalized using the inverse probability function (and the normal distribution.) [In Bliss (1934b), the author notes that two other researchers, Hemmingsen (1933) and Gaddum (1933) had used essentially the same method in a study of toxicity in mice. ]…”