The mechanism of ginsenosides Rg1 and Rb1 promoting glutamic acid release from PC12 cells

AimTo study the mechanism of ginsenosides Rg1 and Rb1 promoting glutamic acid release from PC12 cells. MethodsThe amount of glutamic acid released from PC12 cells was measured by high performance liquid chromatography (HPLC). The effect of Rg1 and Rb1 on the phosphorylation of synapsins was detected with immunofluorescent staining and Western blotting. ResultsBoth Rg1 (10 μmol·L^-1) and Rb1 (10 μmol·L^-1) increased glutamic acid release from PC12 cells. The release of glutamic acid was decreased by pre-incubating with the PKA inhibitor H89. H89 inhibited the release of glutamic acid induced by Rb1, but had no effect on the release of glutamic acid induced by Rg1. Moreover, Rb1 enhanced the phosphorylation of synapsins via PKA pathway, Rg1 was out of touch with this. ConclusionRb1 may promote release of neurotransmitters by increasing the phosphorylation of synapsins via PKA pathway, whereas the up-regulation of neurotransmitters release induced by Rg1 is independent of the phosphorylation of synapsins.