Effect of Cannabinoids HU210 on Glutamate Release of Astrocytes and Its Mechanism
XU Yi;HAN Jing;WANG Wei;ZHU Zhou;Department of Neurology,Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology;Key Laboratory of Modern Teaching Technology of Ministry of Education,Shaanxi Normal University;Department of Plastic Surgery,Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology;
Objective: To investigate the effect of HU210 on glutamate release of cultured midbrain ventral tegmental area(VTA) astrocytes and its mechanism. Methods: VTA astrocytes were cultured. RT-PCR and immunostaining were used to detect the expression of glia fibrillary acidic protein(GFAP) and cannabinoid 1 receptor(CB1R). The cultured VTA astrocytes were randomly divided into 4 groups(n=4): control group(0.2%DMSO in medium), HU210 group(3 μM HU210 in medium), HU210+AM281group(3 μM HU210 + 3 μM AM281 in medium) and HU210 + Riluzole group(3 μM HU210 + 3 μM Riluzole in medium). Concentration of glutamate in medium was detected using enzyme immunoassay of glutamate kit. And then the cultured VTA astrocytes were randomly divided into 2 groups(n=3): control group(0.2%DMSO in medium) and Riluzole group(3 μM Riluzole in medium). Western Bolt was used to detect the expression of glutamate transporter- 1(GLT- 1). Results:Abundant CB1 R RNA and the protein were detected in astrocytes. HU210 increased glutamate release from cultured VTA astrocytes, which was suppressed by AM281. Riluzole suppressed HU210-induced glutamate release from cultured VTA astrocytes and increased the expression of astrocytic GLT- 1 which served to remove the released glutamate. Conclusion: Cannabinoids HU210 probably activates VTA astrocytic CB1 R to release glutamate and Riluzole probably increases the expression of GLT- 1, thus suppressing HU210- induced glutamate release.