title: Vitamin B2 inhibits glutamate release from rat cerebrocortical nerve terminals.
abstract: We examined the effect of riboflavin, vitamin B2, on the release of endogenous glutamate from nerve terminals purified from rat cerebral cortex. The release of glutamate evoked by 4-aminopyridine was inhibited by riboflavin. Further experiments indicated that riboflavin-mediated inhibition of glutamate release (i) results from a reduction of vesicular exocytosis, not from an inhibition of nonvesicular release; (ii) is associated with a decrease in presynaptic N-type and P/Q-type voltage-dependent Ca channel activity. These findings are the first to suggest that, in rat cerebrocortical nerve terminals, riboflavin suppresses voltage-dependent Ca channel activity and in so doing inhibits evoked glutamate release. This finding may explain the neuroprotective effects of vitamin B2 against neurotoxicity.
authors.affiliation: School of Medicine bDepartment of Nutritional Science, Fu Jen Catholic University, Hsin-Chuang, Taipei Hsien, Taiwan.
authors.forename: Su-Jane
authors.initials: SJ
authors.lastname: Wang
authors.forename: Wen-Mein
authors.initials: WM
authors.lastname: Wu
authors.forename: Feili-Lo
authors.initials: FL
authors.lastname: Yang
authors.forename: Guoo-Shyng Wang
authors.initials: GS
authors.lastname: Hsu
authors.forename: Chia-Yu
authors.initials: CY
authors.lastname: Huang
mesh_terms: D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020865:Calcium Channels, P-Type / Q000502:physiology; D020907:Calcium Channels, Q-Type / Q000502:physiology; D020013:Calcium Signaling / Q000187:drug effects; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D005089:Exocytosis / Q000187:drug effects; D005470:Fluorometry; D018698:Glutamic Acid / Q000378:metabolism*; D008297:Male; D009411:Nerve Endings / Q000187:drug effects* / Q000378:metabolism; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012256:Riboflavin / Q000494:pharmacology*; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism; D050496:Vesicular Glutamate Transport Proteins / Q000378:metabolism; D014803:Vitamin B Complex / Q000494:pharmacology; D020960:omega-Conotoxins / Q000494:pharmacology
chemical_list: D002121:Calcium Channel Blockers; D020865:Calcium Channels, P-Type; D020907:Calcium Channels, Q-Type; D050496:Vesicular Glutamate Transport Proteins; D020960:omega-Conotoxins; D014803:Vitamin B Complex; D018698:Glutamic Acid; D015761:4-Aminopyridine; D002118:Calcium; D012256:Riboflavin