Studies of the hypoglycemic brain; amino acids, nucleic acids, total nitrogen, and side-group ionization of proteins in cat brain during insulin coma.

Abstract

A deficiency of glucose supply to the brain is followed by a gradual reduction in carbohydrate reserves, a decrease in oxygen uptake, 1,2 and a reduction in the high-energy phosphates of that organ. 1 In this situation, the compounds which are considered to be the usual free-energy sources have been depleted, and the question becomes: "What are the chemical consequences of this state?" The evidence presented indicates that deep hypoglycemia in the cat or rat does not result in any appreciable change in the quantity of cerebral deoxyribonucleic acid (DNA) or pentose nucleic acid (PNA). However, it does produce alterations in the pattern of the free amino acids, and during profound hypoglycemia a decline in practically all of the amino acids. The total nitrogen and acid-soluble nitrogen content remain practically the same; and the side-group ionization of the proteins is not significantly altered. Method Twelve adult cats were made hypoglycemic