Effect of propofol on glutamate and γ-aminobutyric acid release from rat hippocampal synaptosomes

Abstract

To investigate the effect of propofol on the release of glutamate and γ-aminobutyric acid (GABA) from rat hippocampal synatosomes, synaptosomes was made from hippocampus and incubated with artificial cerebrospinal fluid (aCSF). With the experiment of Ca²⁺-dependent release of glutamate and GABA, dihydrokainic acid (DHK) and nipectic acid were added into aCSF. For the observation of Ca²⁺-independent release of glutamate and GABA, no DHK, nipectic acid and Ca²⁺ were added from aCSF. The release of glutamate and GABA were evoked by 20 μmol/L veratridine or 30 mmol/L KCl. The concentration of glutamate and GABA in aCSF was measured by using high-performance liquid chromatography (HPLC), 30, 100 and 300 μmol/L propofol significantly inhibited veratridine-evoked Ca²⁺-dependent release of glutamate and GABA (P<0.01 orP<0.05). However, propofol showed no effect on elevated KCl-evoked Ca²⁺-dependent release of glutamate and GABA (P>0.05). Veratridine or elevated KCl evoked Ca²⁺-independent release of glutamate and GABA was not affected significantly by propofol (P>0.05). Propofol could inhibit Ca²⁺-dependent release of glutamate and GABA. However, it has no effect on the Ca²⁺-independent release of glutamate and GABA.

Keywords

propofol / hippocampus / synaptosome / glutamate / γ-aminobutyric acid

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