P物质预先给药对去甲肾上腺素诱导大鼠离体心肌细胞β1受体表达的影响

Effects of substance P pretreatment on norepinephrine-induced β1-adrenoreceptor expression in cultured rat cardiomyocytes

目的探讨P物质（SP）预先给药对去甲肾上腺素（NE）诱导大鼠离体心肌细胞β1 受体表达的影响。方法出生1～3dSD大鼠，分离心肌细胞后培养72h。取15孔心肌细胞随机分为5组：C1组不加任何药物，NE1-4组分别给予10^-9、10^-8、10^-7、10^-6mol／LNE，每组3孔。另取12孔心肌细胞随机分为C2组、NE组、SN组和NSN组，每组3孔，NE组加入10^-7mol／LNE，SiN组加入10^-6mol／L SP后30min加入10^-7mol／L NE，NSN组加入NK-1受体拮抗剂$3144后30min加入10^-6mol／LSP,30min后加入10^-7mol／LNE。加入NE后3h时采用流式细胞仪检测心肌细胞融受体表达。结果与C1组比较，NE1-3组心肌细胞口。受体表达上调，NE3组β1受体表达上调最明显（P〈0．05）；与C2组比较，NE组心肌细胞且受体表达上调（P〈0．05）；与NE组比较，SN组心肌细胞融受体表达下调（P〈0．05）。结论SP预先给药可抑制NE诱导的大鼠离体心肌细胞且受体表达上调，其机制可能与NK-1受体激活有关。

Objective To investigate the effects of substance P （SP） pretreatment on the expression of β1-adrenoreceptor （β1-R） induced by norepinephrine （NE） in cultured neonatal rat cardiomyocytes. Methods The cardiomyocytes obtained from 1-3 day old SD rats were cultured for 72 h. The experiment was performed in 2 parts. In part Ⅰ the cells were seeded in 15 well plate and randomly divided into 5 groups （ n = 3 wells each） ： control group （ C1 ） and 4 NE groups were exposed to NE 10^-9 , 10^-8 , 10^-7 , 10^-6 mol/L respectively （NE1.2.3.4）. In part Ⅱ the cells were seeded in 12 well plate and randomly divided into 4 groups （n = 3 wells each） ： group Ⅰ control （C2 ） ： group Ⅱ NE 10^-7 mol/L; group Ⅲ（SN）was pretreated with SP 10^-6 mol/L 30 min before NE 10^-7 mol/L and group Ⅳ （NSN）was treated with NK-1 receptor antagonist （NK-1 tachykinin receptor antagonist,S3144） 30 min before SP pretreatment. After exposure to NE for 3 h the expression of β1-R in the rat cardiomyocytes was detected using flow cytometry. Results In part Ⅰ the expression of β1-R was significantly higher in group NE1-3 than in control group （C1）, with the highest expression in group NE3. In part Ⅱ the expression of β1-R was significantly higher in group Ⅱ （NE） than in control group （C2） while lower in group Ⅲ （SN） than in control group Ⅱ （NE）. There was no significant difference in the expression of β1- R between group Ⅰ （C2） and group Ⅲ and Ⅳ （NSN）. Conclusion Substance P pretreatment can inhibit the up, regulation of β1-R expression in cultured rat cardiomyocytes induced by norepinephrine through activating NK-1 receptor.