CCK-8对LPS诱导大鼠TASMCs CuZn-SOD基因表达影响的受体机制

Effect of CCK-8 receptor on the LPS-induced CuZn-SOD mRNA expression in rat vascular smooth muscle cells

目的探讨八肽胆囊收缩素(CCK-8)对体外脂多糖(LPS)诱导大鼠胸主动脉平滑肌细胞(TASMCs)CuZn-SOD基因表达影响的受体机制。方法用贴块法培养大鼠TASMCs,经CCK-8、LPS、CR-1409、CR-2945、CCK+LPS、CR-1409+LPS、CR-2945+LPS、CR-1409+CCK-8+LPS、CR-2945+CCK-8+LPS及溶剂单独或共同孵育细胞,用RT-PCR技术检测CuZn-SOD mRNA表达。结果对照组TASMCs CuZn-SOD mRNA低水平表达,LPS诱导TASMCs CuZn-SOD mRNA表达上调(P<0.05),CCK-8预处理后,LPS对TASMCs CuZn-SOD mRNA表达的诱导作用可部分受抑,预先用CR-1409(1×10-5mol/L)、CR-2945(1×10-5mol/L)处理后,再分别加入LPS和CCK-8,CR-1409+CCK-8+LPS、CR-2945+CCK-8+LPS两组CuZn-SOD mRNA表达均高于CCK-8+LPS组(P<0.01),但仍低于LPS组(P<0.05),其中CR-2945的拮抗作用比CR-1409稍明显;CR-1409、2945单独作用与对照组相比差异无显著性(P>0.05)。结论CCK-8通过其受体下调LPS对TASMCs CuZn-SOD基因表达的诱导作用,其中CCK-BR较CCK-AR作用稍大。

Objective To investigate the effect of CCK - 8 receptor on LPS - induced CuZn - SOD mRNA expres- sion in rat TASMCs. Methods Rat thoracic aorta smooth muscle cells （TASMCs） from the attachment - block culture were incubated with NS, LPS （0.1 rag/L）, CCK- 8 （1 × 10^-8 mol/L）, CR- 1409 （1 × 10^-5 mol/L, the specific antagonist of CCK - AR） and CR -2945 （ 1 × 10^-5 mol/L, the specific antagonist of CCK - BR）, respectively or in combination. The expressions of CuZn - SOD mRNA were assayed by RT - PCR. Results The expressions of LPS - induced CuZn - SOD mRNA were up - regulated, compared with the control group （ P 〈 0.05 ）. Subsequent to CCK - 8 pretreatment, the induction of LPS to the expressions of CuZn - SOD mRNA in TASMCs was partially inhibited. Following pretreatment with CR - 1409 （ 1 × 10^ -5 mol/L） and CR - 2945 （ 1 × 10^-5 mol/L）, LPS and CCK - 8 were respectively add- ed. The expressions in CR - 1409 ＋ CCK - 8 ＋ LPS and CR - 2945 ＋ CCK - 8 ＋ LPS groups were higher than CCK - 8 ＋ LPS group （ P 〈 0.01 ）, but were still lower than those of LPS group （ P 〈 0.05 ）. The antagonist effect of CR - 2945 was slightly more evident than that of CR - 1409, while either CR - 1409 or CR - 2945 alone had no significant differences in comparison with the control group （ P 〉 0.05）. Conclusion CCK - 8 can down - regulate LPS - induced CuZn - SOD mRNA expression in TASMCs by means of its receptors CCK - AR and CCK - BR, of which CCK - BR had slightly grea- ter induction than CCK- AR.