Withdrawal from chronic ginsenoside Rbl treatment alters GABA_A receptor mRNA levels of cultured rat hippocampal neurons

摘要

Ginsenoside, one of major active ingredients of Panax ginseng, is involved in regulating synaptic transmission and has beneficial effects on protecting neuron. It was in the current study investigated the effects of withdrawal from chronic treatment of ginsenoside Rb1 and DZ on γ-aminobutyric acid receptor (GABAR) subunits gene expression on hippocampal neurons. Exposure of cultured rat hippocampal neurons to 10μM ginsenoside Rb1 for 5 days reduced the amounts of α1, γ2, and β2 subunit mRNAs, whereas Rb1 withdrawal was associated with a persistent reduction in γ2, and β2 subunit mRNAs and an increase in α5 mRNAs. Treatment with 10μM Diazepam (DZ) for 5 days reduced the amount of α1 subunit mRNA, whereas DZ withdrawal did not significantly affect the abundance of all the GABA_A subunits. The data suggest that chronic and withdrawal ginsenoside Rb1 treatment of rat hippocampal neurons in culture causes alterations in the gene expression of GABAA receptors and ginsenoside Rb1 might have a different mechanism of action and unique receptor binding sites from that of the DZ.