Toosendanin-induced inhibition of small-conductance calcium-activated potassium channels in CA1 pyramidal neurons of rat hippocampus

被引：20

作者：

Wang, ZF ^{[1
]}

Shi, YL ^{[1
]}

机构：

[1] Chinese Acad Sci, Shanghai Inst Biol Sci, Inst Physiol, Key Lab Neurobiol, Shanghai 200031, Peoples R China

来源：

NEUROSCIENCE LETTERS | 2001年 / 303卷 / 01期

基金：

中国国家自然科学基金;

关键词：

toosendanin; small-conductance calcium-activated potassium channel; hippocampus; patch clamp; single-channel recording; rat;

D O I：

10.1016/S0304-3940(01)01682-2

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

The effect of toosendanin (TSN) on small-conductance calcium-activated potassium channels (SKca) in pyramidal neurons of rat hippocampal CA1 region was observed using the inside-out configuration of patch-clamp technique. The results showed that TSN (1.7 similar to 170 muM) inhibited the SKca activity by reducing the open probability and open frequency significantly in a concentration-dependent manner, and the effects were partially reversible. Elevating Ca2+ concentration at the intracellular side of the patch ([Ca2+](i)) from 1 to 10 muM decreased the inhibitory efficacy. Analysis of the channel kinetics indicated that TSN increased the slow closed time constant significantly, while open time and unitary conductance of channel did not change. These data provide a further explanation for TSN-induced facilitation of neurotransmitter release and antibotulismic effects of the drug. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

引用

页码：13 / 16

页数：4

共 19 条

[1] Toosendanin-induced change of dopamine level detected by microdialysis in vivo at rat striatum [J].

Chen, WY ;

Yin, PB ;

Ye, WL ;

Shi, YL .

CHINESE SCIENCE BULLETIN, 1999, 44 (12) :1106-1110

[2] IMPROVED PATCH-CLAMP TECHNIQUES FOR HIGH-RESOLUTION CURRENT RECORDING FROM CELLS AND CELL-FREE MEMBRANE PATCHES [J].

HAMILL, OP ;

MARTY, A ;

NEHER, E ;

SAKMANN, B ;

SIGWORTH, FJ .

PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY, 1981, 391 (02) :85-100

[3] Inhibition of Toosendanin on the delayed rectifier potassium current in neuroblastoma X glioma NG108-15 cells [J].

Hu, Q ;

Huang, FS ;

Shi, YL .

BRAIN RESEARCH, 1997, 751 (01) :47-53

[4] MECHANICAL AND ENZYMATIC ISOLATION OF MAMMALIAN CNS NEURONS [J].

KANEDA, M ;

NAKAMURA, H ;

AKAIKE, N .

NEUROSCIENCE RESEARCH, 1988, 5 (04) :299-315

[5] MUSCARINIC AND BETA-ADRENERGIC DEPRESSION OF THE SLOW CA-2+-ACTIVATED POTASSIUM CONDUCTANCE IN HIPPOCAMPAL CA3 PYRAMIDAL CELLS IS NOT MEDIATED BY A REDUCTION OF DEPOLARIZATION-INDUCED CYTOSOLIC CA-2+-TRANSIENTS [J].

KNOPFEL, T ;

VRANESIC, I ;

GAHWILER, BH ;

BROWN, DA .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1990, 87 (11) :4083-4087

[6] CALCIUM-DEPENDENT CURRENT GENERATING THE AFTERHYPERPOLARIZATION OF HIPPOCAMPAL-NEURONS [J].

LANCASTER, B ;

ADAMS, PR .

JOURNAL OF NEUROPHYSIOLOGY, 1986, 55 (06) :1268-1282

[7] PROPERTIES OF 2 CALCIUM-ACTIVATED HYPERPOLARIZATIONS IN RAT HIPPOCAMPAL-NEURONS [J].

LANCASTER, B ;

NICOLL, RA .

JOURNAL OF PHYSIOLOGY-LONDON, 1987, 389 :187-203

[8]

Li Peizhong, 1982, Chin. J. Tradit. Chin. Med., V13, P28

[9] THE COUPLING OF NEUROTRANSMITTER RECEPTORS TO ION CHANNELS IN THE BRAIN [J].

NICOLL, RA .

SCIENCE, 1988, 241 (4865) :545-551

[10]

SHEN GG, 1994, ACTA PHYSL SIN, V46, P546

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