Long-lasting changes in regional brain amino acids and monoamines in recovered pyrithiamine treated rats.
Rats were subjected to a severe bout of thiamine deficiency induced by daily pyrithiamine + a thiamine deficient diet, reversed by thiamine administration and allowed to recover. Pyrithiamine treated animals demonstrated impaired retention of a 24 h recall of passive avoidance. Regional brain concentration of norepinephrine, dopamine, serotonin, 3,4-dihydroxyphenylacetic acid, 5-hydroxyindoleacetic acid, GABA, glutamate, aspartate, glutamine, and glycine were determined after 2 and 9 weeks of nutritional recovery. A significant increase in NE content of cerebellum from the pyrithiamine treated animals was observed at both 2 and 9 week recovery periods. The concentrations of serotonin and its metabolite were significantly elevated in midbrain-thalamus and striatum. Significant reductions of GABA and glutamate were also observed in midbrain-thalamus. Amino acid levels in all other brain areas were unchanged from pair-fed controls. These results suggest regionally specific, chronic alterations in GABA, glutamate, serotonin, and norepinephrine activity following recovery from an acute bout of pyrithiamine-induced thiamine deficiency. The absence of a permanent reduction of cortical norepinephrine similar to that observed in an earlier study is discussed.
Langlais
P J
PJ
Research Svc., V.A. Medical Center, Brockton, MA 02401.
Mair
R G
RG
Anderson
C D
CD
McEntee
W J
WJ
D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D015306:Biogenic Monoamines / Q000032:analysis*; D001923:Brain Chemistry / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D008297:Male; D011726:Pyridinium Compounds / Q000494:pharmacology*; D011745:Pyrithiamine / Q000494:pharmacology*; D051381:Rats; D013832:Thiamine Deficiency / Q000378:metabolism*
D000596:Amino Acids; D015306:Biogenic Monoamines; D011726:Pyridinium Compounds; D011745:Pyrithiamine