alpha-Sialylcholesterol enhances the depolarization-induced release of acetylcholine and glutamate in rat hippocampus: in vivo microdialysis study.
The effects of alpha-sialylcholesterol (alpha-SC), a synthetic ganglioside analogue, on synaptic neurotransmission were studied using in vivo microdialysis technique. Application of alpha-SC through a microdialysis probe enhanced high potassium-evoked release of acetylcholine and glutamate in the hippocampal CA3 region of Wistar rats. The experiments using synaptosomes and FM1-43, a fluorescent styryl dye used for studies of neurotransmitter release mechanisms, showed that alpha-SC increased depolarization-induced loss of dye but it did not evoke the dye loss at resting condition. These results indicate that alpha-SC promotes a depolarization-induced exocytotic neurotransmitter release in the brain under in vivo conditions. Application of alpha-SC increased the level of glutamate but not that of acetylcholine, suggesting that alpha-SC affects spontaneous glutamate release and/or transport system at the brain region.
Tanaka
Yasukazu
Y
Neuronal Function Research Group, Division of Neuroscience and Brain Function, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakaecho, Itabashi-ku, Tokyo 173-0015, Japan. yasu@center.tmig.or.jp
Han
Huiwan
H
Hagishita
Tairo
T
Fukui
Fumiko
F
Liu
Guoquan
G
Ando
Susumu
S
D000109:Acetylcholine / Q000378:metabolism*; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002788:Cholesterol Esters / Q000494:pharmacology*; D005089:Exocytosis / Q000187:drug effects / Q000502:physiology; D045604:Extracellular Fluid / Q000187:drug effects / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D017551:Microdialysis; D011188:Potassium / Q000378:metabolism / Q000494:pharmacology; D017729:Presynaptic Terminals / Q000187:drug effects* / Q000378:metabolism; D011726:Pyridinium Compounds / Q000493:pharmacokinetics; D000644:Quaternary Ammonium Compounds / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D012794:Sialic Acids / Q000494:pharmacology*; D009435:Synaptic Transmission / Q000187:drug effects* / Q000502:physiology; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism
D002788:Cholesterol Esters; C073804:FM1 43; D011726:Pyridinium Compounds; D000644:Quaternary Ammonium Compounds; D012794:Sialic Acids; C055195:N-acetylneuraminyl cholesterol; D018698:Glutamic Acid; D000109:Acetylcholine; D011188:Potassium