This work was supported by U.S. Public Health Service Grant 5-PO1-NB-06208.
THE INFLUENCE OF TYROSINE, PHENYLPYRUVATE AND VITAMIN B6 UPON SEIZURE THRESHOLDS 1
Article first published online: 12 DEC 2006
Journal of Neurochemistry
Volume 18, Issue 6, pages 799–808, June 1971
How to Cite
Gallagher, B. B. (1971), THE INFLUENCE OF TYROSINE, PHENYLPYRUVATE AND VITAMIN B6 UPON SEIZURE THRESHOLDS . Journal of Neurochemistry, 18: 799–808. doi: 10.1111/j.1471-4159.1971.tb12009.x
- Issue published online: 12 DEC 2006
- Article first published online: 12 DEC 2006
- (Received 3 June 1970. Accepted 1 September 1970)
Abstract— Thresholds to the first appearance of a myoclonic jerk and to the appearance of tonic-clonic seizures induced by the convulsant, hexafiuorodiethyl ether, were examined in immature rats at sequential time intervals following the administration of L-tyrosine, L-phenylalanine, Na-phenylpyruvate and several forms of vitamin B6. l-Tyrosine failed to lower either seizure threshold even though plasma and brain levels of tyrosine exceeded those obtained with a dose of phenylalanine that was effective in lowering threshold. Na-phenylpyruvate lowered both seizure thresholds at a time that correlated with elevation of brain phenylalanine. Pyridoxine hydrochloride, pyridoxal-5′-phosphate and pyridoxamine phosphate all lowered both seizure thresholds. The time course and dose dependency of the effects of B6 vitamers were examined; the effect of phenylalanine on seizure threshold was unrelated to derived tyrosine or phenylpyruvate and vitamin B6 was not involved. The enhanced cerebral excitability following administration of B6 vitamers is discussed.