中国药理学与毒理学杂志
中國藥理學與毒理學雜誌
중국약이학여독이학잡지
CHINESE JOURNAL OF PHARMACOLOGY AND TOXICOLOGY
2004年
5期
321-326
,共6页
许彤辉%施玉樑%任小梅%周建营
許彤輝%施玉樑%任小梅%週建營
허동휘%시옥량%임소매%주건영
川楝素%大脑皮质%突触体%氨基酸神经递质%谷氨酸%神经递质调节剂%卡西霉素%4-氨基吡啶
川楝素%大腦皮質%突觸體%氨基痠神經遞質%穀氨痠%神經遞質調節劑%卡西黴素%4-氨基吡啶
천련소%대뇌피질%돌촉체%안기산신경체질%곡안산%신경체질조절제%잡서매소%4-안기필정
toosendanin%cerebral cortex%synaptosomes%amino acid neurotransmitters%glutamates%neurotransmitter agents%calcimycin%4-aminopyridine
目的阐释川楝素的作用机制,为了解递质解释的基本过程提供线索.方法以大鼠大脑皮层匀浆经密度梯度离心分离获得的突触体作为研究标本,分别施加50 mmol·L-1 KCl,1.5μmol·L-1卡西霉素或7.5mmlo·L-14-氨基吡啶触发谷氨酸(Glu)释放。通过检测由Glu氧化脱氢反应与NAD+生成的NADH荧光变化测定Glu释放量.结果川楝素浓度、时间依赖地显著摄制由KCl诱发的Glu释放,并主要抑制钙依赖性释放;由卡西霉素直接提升胞内钙离子浓度而诱发的Glu释放也被川楝素明显抑制。结论川楝素抑制中枢突触Glu释放,该效应与其导致的递质释放机制中钙离子敏感性降低有关.
目的闡釋川楝素的作用機製,為瞭解遞質解釋的基本過程提供線索.方法以大鼠大腦皮層勻漿經密度梯度離心分離穫得的突觸體作為研究標本,分彆施加50 mmol·L-1 KCl,1.5μmol·L-1卡西黴素或7.5mmlo·L-14-氨基吡啶觸髮穀氨痠(Glu)釋放。通過檢測由Glu氧化脫氫反應與NAD+生成的NADH熒光變化測定Glu釋放量.結果川楝素濃度、時間依賴地顯著攝製由KCl誘髮的Glu釋放,併主要抑製鈣依賴性釋放;由卡西黴素直接提升胞內鈣離子濃度而誘髮的Glu釋放也被川楝素明顯抑製。結論川楝素抑製中樞突觸Glu釋放,該效應與其導緻的遞質釋放機製中鈣離子敏感性降低有關.
목적천석천련소적작용궤제,위료해체질해석적기본과정제공선색.방법이대서대뇌피층균장경밀도제도리심분리획득적돌촉체작위연구표본,분별시가50 mmol·L-1 KCl,1.5μmol·L-1잡서매소혹7.5mmlo·L-14-안기필정촉발곡안산(Glu)석방。통과검측유Glu양화탈경반응여NAD+생성적NADH형광변화측정Glu석방량.결과천련소농도、시간의뢰지현저섭제유KCl유발적Glu석방,병주요억제개의뢰성석방;유잡서매소직접제승포내개리자농도이유발적Glu석방야피천련소명현억제。결론천련소억제중추돌촉Glu석방,해효응여기도치적체질석방궤제중개리자민감성강저유관.
AIM To elucidate the mechanism of the action of toosendanin(TSN), which may provide a new clue for understanding the basic processes involved in transmitter release. METHODS Nerve terminals (synaptosomes) from rat cerebral cortex were used as a test system to study the effects of TSN. They were isolated by discontinuous density gradient centrifugation. The secretogogues used to evoke Glu release included 50 mmol·L-1 KCl, 1.5 μmol·L-1 calcimycin and 7.5 mmol·L-1 4-aminopyridine (4-AP). Glu released from synaptosomes was determined by measuring the fluorescence of NADH produced in oxidative dehydrogenation of Glu. RESULTSTSN obviously inhibited the Glu release evoked by KCl depolarization in a concentration- and time-dependent manner. The effect mainly resulted from TSN-induced block of the Ca2+-dependent transmitter release. After TSN application the Glu release evoked by elevating intracellular free-Ca2+ concentration ([Ca2+]i) with calcimycin also significantly decreased. CONCLUSIONTSN inhibited the Glu release from central synapses and the effect was assumed to be related to TSN-induced depression in the Ca2+-sensitivity of release machinery.