【摘要】 目的研究过氧化物酶体活化增殖受体γ(PPAR-γ)在自发性高血压大鼠(SHR)动脉血管平滑肌的表达随龄性变化,探讨PPAR-γ与高血压的发生发展关系。方法采用免疫组织化学方法检测PPAR-γ在不同周龄SHR血管组织表达变化,同时培养大鼠血管平滑肌细胞(VSMCs),用RT-PCR检测PPAR-γmRNA,用WesternBlot分析PPAR-γ蛋白在不同周龄大鼠原代及低代培养的VSMCs表达。采用同龄同种系正常血压的京都种大鼠(WKY)作为对照组。结果PPAR-γ在SHR血管组织的表达有随着鼠龄增加而增强的趋势,而24周与16周相比表达不再增加。PPAR-γ在4周和24周SHR和WKY表达差异无统计学意义,而8周和16周SHR的PPAR-γ表达明显高于WKY。在VSMCs,4周、8周和16周SHR和WKY的PPAR-γmRNA以及蛋白表达随着鼠龄的增加而增加。4周和24周SHR与WKY相比PPAR-γmRNA以及蛋白表达差异无统计学意义,但是PPAR-γ表达量在8周、16周SHRVSMCs表达高于WKY,24周时在SHRVSMCs表达不再增加,表达量与同龄WKY相当。结论PPAR-γ的表达随着血压、血管平滑肌增殖和鼠龄的变化而有所不同,此变化提示PPAR-γ参与了高血压的发生发展。更多还原

【Abstract】 Objective In order to elucidate the relationship between PPAR-γ and the development of hypertension, we detected the expression of peroxisome proliferator-activated receptors γ(PPAR-γ) in the vascular smooth muscle cells (VSMCs)and the VSMC proliferation of spontaneously hypertensive rats (SHR) at different ages. Methods The expression of PPAR-γ in the intact vascular tissues of rats at different ages were detected by immunohistochemistry. Aortic VSMCs were cultured. PPAR-γ mRNA in primary and low-passage cultured VSMCs of various ages were determined by RT-PCR, and proteins were evaluated by immunohistochemistry and age matched Western Blot. Age matched Wistar-Kyoto rats (WKY) were used as control. Results This experiment demonstrated that the expression of PPAR-γ increased with age in the intact aorta tissues of SHR. The expression of PPAR-γ did not continuously increase in 24w-old SHR when compared with that in 16w-old SHR. No difference between 4w-, 24w-old SHR and age matched WKY was observed, but the expression of PPAR-γ was greater in 8w- and 16w old SHR than in age matched WKY. In primary and low-passage cultured VSMCs, the expression of PPAR-γ mRNA and protein increased with age both in SHR VSMCs and WKY VSMCs of 4w,8w and 16w old, and no difference between 4w- and 24w-old SHR and WKY was noted, but the expression of PPAR-γ was higher in 8w- and 16w-old SHR than in age matched WKY. PPAR-γ expression in 24w-old SHR did not increase and it was equal to 16w-old SHR and 24w-old WKY. Conclusion These datas on SHR suggest that the expression of PPAR-γ changes with age and the development of high blood pressure. PPAR-γ expression may play a compensatory role in hypertension, but this compensatory action is limited.更多还原