Effect of Insulin Hypoglycemia and Glucose Administration on the Level of the Glutamine-like Substance in Blood Serum.

That insulin hypoglycemic therapy in mental patients lowers the level of amino acids in the blood has been pointed out in a previous publication (1). Some investigators have reported that insulin and carbohydrate administrations decrease protein metabolism (2, 3, 4). In the preceding paper, it was pointed out that glutamine might play a role in intermediary nitrogen metabolism and experiments were reported which demonstrated the presence of a glutamine-like substance (GLS) 1 in spinal fluid and blood serum and plasma, with many indications that this substance is most likely glutamine. This paper deals with the effect of insulin hypoglycemia and of carbohydrate administration upon the level of this substance in the blood.