神经肽Y诱导血管平滑肌细胞凋亡相关基因表达与细胞内液pH变化的关系

The Relationship between Expression of Apoptosis-Related Genes Induced by Neuropeptide Y and Changes of Intracellular pH in Vascular Smooth Muscle Cells

为探讨细胞内液pH在神经肽Y诱导血管平滑肌细胞凋亡过程中的变化 ,以体外培养血管平滑肌细胞模型为研究对象 ,运用激光共聚焦显微镜和免疫荧光组织化学技术 ,定量和动态观察研究神经肽Y诱导血管平滑肌细胞凋亡相关基因bcl 2和bax表达与细胞内液pH变化之间的关系。结果发现 ,在神经肽Y作用下 ,体外培养的血管平滑肌细胞凋亡相关基因bcl 2和bax表达的平均荧光值分别为 134 9.6 7± 10 8.2 8和 1397.5 0± 10 4.43,与对照组的 986 .6 4± 91.2 2和 10 6 0 .44± 10 7.5 4相比 ,差异明显 (P <0 .0 1) ,bax与bcl 2两者平均荧光值之比为 1.0 4;神经肽Y还可降低血管平滑肌细胞内液pH的平均荧光值 ,使细胞浆酸化。此结果提示 ,神经肽Y诱导血管平滑肌细胞凋亡相关基因的表达与神经肽Y降低细胞内液酸碱度、细胞浆酸化有关。

Aim To explore the role of changes of intracellular pH in expression of apoptosis-related genes of cultured vascular smooth cells induced by neuropeptide Y. Methods The rat vascular smooth muscle cells were used for experiments at passage 4 to 6. The expression of bcl-2 and bax were quantitatively detected in cultured vascular smooth muscle cells and the intracellular pH were also quantitatively detected with the immunofluorescent quantitative skill through Laser scanning confocal microscope (ACAS570). Results It was found that at the action of NPY (10 -6 mmol/L), bcl-2 and bax were markedly expressed in cultured smooth muscle cells compared with control group. The fluorescent value of bcl-2 and bax were 1 349.67±108.28 and 1397.50±104.43, much higher than 921.72±80.31 and 1 060.44±107.54 in the control group respectively (P<0.01). Intracellular fluid pH in VSMC was decreased by NPY. Conclusion The expression of apoptosis-related genes induced by neuropeptide Y is mediated, in part, by intracellular acidosis in cultured vascular smooth muscle cells.