The Inhibitory Effects of Jujuboside A on Rat Hippocampus in Vivo and in Vitro

Abstract

Jujuboside A (JuA) is a glycoside extracted from the seed of Ziziphus jujuba Mill var. spinosa (Bunge) Hu ex H F Chou, a Chinese herbal medicine, which has long been known as a sedative-hypnotic drug. The present study used the method of intracerebroventricular (i. c. v.) JuA in vivo to detect the effect of JuA on paired-pulse responses of dentate gyrus granule cells in urethane-anaesthetized rats, and the method of hippocampal slice bathing in JuA in vitro to detect the effects of JuA on the responses of CA1 pyramidal cells. The results showed that JuA significantly decreased the slopes of excitatory postsynaptic potential (EPSP) and the amplitudes of population spike (PS) in the first responses of granule cells and significantly decreased EPSP and PS in the responses of CA1 pyramidal cells. The good quantitative correspondence between in vitro and in vivo results indicates that studies using hippocampal formation allow research on the inhibitory effects of JuA in the rat central nervous system (CNS). In conclusion, our study accessed the inhibitory effects of JuA on hippocampal formation in vivo and in vitro, which contributed to the further research on the mechanism of its effects on CNS.

Abbreviations

ACSF:artificial cerebrospinal fluid

CaM:calmodulin

CNS:central nervous system

DG:dentate gyrus

EPSP:excitatory postsynaptic potential

EPSP1:the slope of the EPSP of the first pulse

EPSP2:the slope of the EPSP of the second pulse

GABA:γ-amino-butyric acid

i.c.v.:intracerebroventricular

JuA:jujuboside A

NGF:nerve growth factor

NMDA:N-methyl-D-aspartic acid

PP:perforant pathway

PS:population spike

PS1:the amplitude of PS of the first pulse

PS2:the amplitude of PS of the second pulse

PSL1:the latency of the PS1

PSL2:the latency of the PS2

Ziziphus:Ziziphus jujuba Mill var. spinosa (Bunge) Hu ex H F Chou

Key words

Jujuboside A - Ziziphus jujuba - Rhamnaceae - hippocampal formation - inhibitory effects

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