Experimental studies on glutamic acid in rabbits brain with repeated convulsions Part Ⅰ. On free amino-nitrogen and glutamic acid in rabbits brain with repeated convulsions

The changes of the amount of free amino-nitrogen and glutamic acid were investigated in the rabbits brain with repeated convulsions caused by hexogen. The free amino-nitrogen was measured by Van-Slyke-Neil gasmetric apparatus, and the glutamic acid was measured by Warburg gasmetric apparatus with glutamic acid decarboxylase. The results were as follows. Normal Rabbits Brain During Repeated Convulsions 20-24 Hours after Repeated Convulsions Free Amino-nitrogen 0.4553 mg/g 0.3006 mg/g 0.3324 mg/g Glutamic acid 1.5501 mg/g 0.9543 mg/g 1.2425 mg/g The free amino-nitrogen as well as the glutamic acid were the most in the normal brain and the least during the repeated convulsion, and they showed a certain increase at 20-24 hours after the repeated convulsions compared with those during the convulsions, but still apart from the normal. Glycolysis was depressed by sodium glutamate in the normal rabbits brain which had enough glutamic acid, but the glycolysis was rather accelerated by sodium glutamate in the rabbits brain which had repeated convulsions and thus scarce glutamic acid, when the sodium glutamate was added to the irrigating fluid of the vessels in the brain and then the glycolysis was measured in each irrigating fluid before and after irrigation. Therefore, it could be concluded that sodium glutamate has the effect of regulation to keep the normal and moderate glycolysis in the brain