Xlv. the Behaviour of Whole Blood towards Maltose in Vitro. by Alexander Hynd and Marjorie

MALTOSE is the only disaccharide which, on subcutaneous injection, has been found capable of alleviating the symptoms caused by insulin. As has been shown by Herring, Irvine and Macleod [1924], its action, in this respect, in the case of mice is almost as efficient as that of glucose or mannose, but with larger animals, such as rabbits, cats or dogs, it is less effective. Even with mice, it exercises its action more slowly than glucose and this would suggest that maltose requires to undergo hydrolysis before it can counteract the action of insulin. Further, the inequality in the rates of hydrolysis of maltose might account for the difference in the results obtained in different species of animals. Support for this view seemed to be furnished by the results of investigations on the maltase content of blood-serum reported by Compton [1921]. This worker found that the maltase content of the blood was not the same in all animals and he divided mammals into two groups, according to whether they had or had not maltase in their blood. Unfortunately, Compton did not include the mouse amongst the animals he investigated, and the experiments now recorded were undertaken, initially at least, to determine whether the greater efficiency of maltose in relieving mice from the effects of an injection of insulin could be correlated with a greater maltase content of the blood in this animal than in larger animals such as the rabbit or dog.