PHYSIOLOGY AND BIOCHEMISTRY 



The fact that, in the experimental animal and presumably in 

 many diabetic patients, eight-tenths of the insulin-producing capacity 

 of the islet cells must disappear before it is possible to detect the insulin- 

 producing capacity by any procedure except direct examination, pre- 

 sents a challenge to clinicians and experimentalists alike. It is incon- 

 ceivable that a relatively clear-cut problem of this kind can long resist 

 the onslaught of the vigorous minds which we hope will attack it now that 

 peace is restored. Many physiological and chemical avenues of ap- 

 proach have not as yet been adequately explored. 



Improvement of Insulin as a Therapeutic Agent. The prob- 

 lem of giving insulin in a more physiological way presents many diffi- 

 culties. It will not be easy to make a compound of insulin which is 

 broken down at an increasing rate as the sugar content of the tissues 

 rises. Improvements in protamine zinc insulin are quite possible and 

 should certainly engage the attention of those who have already made 

 great strides in this field. There are indications that a decrease in the 

 amount of protamine with respect to insulin, may serve a useful pur- 

 pose. Clear solutions of combined insulin which produce a prolonged 

 effect are desirable, but clinical opinion indicates that a completely 

 satisfactory one is not as yet available. Insulin by mouth for mild cases 

 of diabetes is by no means an impossibility, but it will probably always 

 remain a wasteful procedure and in cases in which dosage of insulin 

 must be very accurately regulated, a hazardous one. 



It should be possible in the future to make a more definite 

 separation of the diabetic cases into those which have retained a definite 

 capacity for producing insulin and those in whom this function of the 

 islet cells is irretrievably lost. In the former type, it is obviously use- 

 less to plan diets with the idea of conserving islet function. In experi- 

 mental animals, diabetes resulting from partial removal of the pancreas 

 or from administration of the diabetogenic material of the anterior 

 pituitary gland, may now, under certain conditions, be prevented, or 

 in its early stages cured, by the appropriate use of insulin and diets 

 which do not tax the capacity of the remaining islands of Langerhans. 

 These findings have aroused the hope that a similar application may 

 be made in those cases of human diabetes in which a reasonable 

 number of functioning islet cells remains. This application will not 

 be easy until the potential human diabetic can be recognized much 

 earlier than is possible at present and until much more light is shed 



