麦芽总生物碱上调多巴胺D2受体抑制垂体瘤细胞泌乳素表达和分泌

Maltol total alkaloid inhibits expression and secretion of prolactin by upregulating dopamine D2 receptor

目的研究多巴胺D2受体(D2R)在麦芽总生物碱调控泌乳素(PRL)分泌过程中的作用。方法大鼠垂体瘤MMQ、GH3细胞分为对照组、溴隐亭(5μg/mL)组、麦芽总生物碱(4.4、8.8、35.2、70.4μg/mL)组、氟哌啶醇(10、20、40μg/mL)组、麦芽总生物碱与氟哌啶醇联合给药组。采用CCK-8法检测细胞活力;Western blotting检测PRL、D2R蛋白表达;ELISA法检测细胞上清PRL水平;qRT-PCR法检测PRL、D2R mRNA表达。结果与对照组相比,麦芽总生物碱(35.2、70.4μg/mL)可显著下调MMQ细胞PRL蛋白及mRNA表达、上清PRL水平(P<0.05),显著上调MMQ细胞D2R蛋白及mRNA水平(P<0.05);氟哌啶醇可显著减弱麦芽总生物碱对MMQ细胞PRL蛋白及mRNA表达、上清PRL水平的下调(P<0.05),并显著减弱麦芽总生物碱对MMQ细胞D2R蛋白及mRNA表达的上调(P<0.05);麦芽总生物碱对GH3细胞PRL表达、上清PRL水平无显著影响。结论麦芽总生物碱通过上调D2R表达,从而抑制MMQ细胞PRL的表达和分泌。

Objective To study the role of dopamine D2 receptor(D2R)on the regulation of prolactin(PRL)secretion by malt total alkaloids.Methods MMQ and GH3 cells of pituitary adenoma were divided into control group,bromocriptine(5μg/mL),malt total alkaloids(4.4,8.8,35.2,70.4μg/mL),haloperidol(10,20,40μg/mL),and combined administration group of total malt alkaloids and haloperidol.Cell viability was detected by CCK-8;The expressions of PRL and D2R were detected by western blotting;The level of PRL was detected by ELISA;The level of PRL and D2R mRNA were detected by qRT-PCR.Results Compared with control group,malt alkaloids(35.2,70.4μg/mL)significantly reduced the expression levels of PRL protein and mRNA,and the level of PRL in the supernatant of MMQ cells(P<0.05).Malt alkaloids(35.2,70.4μg/mL)significantly increased the expression levels of D2R protein and mRNA in MMQ cells.Haloperidol significantly inhibited the downregulation of malt alkaloids on the expression levels of PRL protein and mRNA,and the expression level of PRL in supernatant of MMQ cells(P<0.05).Haloperidol significantly inhibited the upregulation of malt alkaloids on the levels of D2R protein and mRNA(P<0.05).The level of PRL in GH3 cells had no change by malt alkaloids.Conclusion Malt alkaloids could inhibit the expression and secretion of PRL in MMQ cell by upregulating D2R.