title: [Membrane cholesterol oxidation effects on synaptic vesicle cycle in frog (RANA ridibunda) motor nerve terminals].
abstract: In experiments on frog (Rana ridibunda) neuromuscular junction the influence of cholesterol oxidation on the presynaptic vesicular cycle was investigated. Application of cholesterol oxidase (1 u. a.) during 1/2 hour led to the oxidation of - 0.007 mg cholesterol per 1 g tissue and reduced stability of lipid rafts in the nerve terminals. Using electrophysiological techniques it was shown that the cholesterol oxidation decreases the evoked neurotransmitter release. In experiments with fluorescent FM-dyes the depression of the synaptic vesicles exo-endocytosis and the dispersion of synaptic vesicles clusters were revealed. Comparative analysis of electrophysiological and optical data, as well as experiments with water soluble quencher of FM-dye indicated the possibility of some neurotransmitter release by "kiss-and-run" pathway, when short-lived fusion pore is formed. It was concluded that cholesterol oxidation inhibit evoked exocytosis, and also synaptic vesicle delivery from reserve pool to cites of exocytosis probably by break of the clusterization. Perhaps the synaptic vesicles of recycling pool release the neurotransmitter using the kiss-and-run mechanism.
authors: A M
authors: AM
authors: Petrov
authors: M R
authors: MR
authors: Kasimov
authors: A R
authors: AR
authors: Giniatullin
authors: A L
authors: AL
authors: Zefirov
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology; D002784:Cholesterol / Q000378:metabolism*; D002789:Cholesterol Oxidase / Q000008:administration & dosage; D005089:Exocytosis / Q000187:drug effects; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism; D009046:Motor Neurons / Q000378:metabolism / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism; D009469:Neuromuscular Junction / Q000378:metabolism / Q000502:physiology; D011895:Rana ridibunda / Q000502:physiology; D009435:Synaptic Transmission; D013572:Synaptic Vesicles / Q000187:drug effects / Q000378:metabolism / Q000502:physiology
chemical_list: D002784:Cholesterol; D002789:Cholesterol Oxidase