Takahashi Kazuhiro, Totsune Kazuhito, Kikuchi Kumi, Murakami Osamu
Department of Analytical Medical Technology, Tohoku University School of Health Sciences, Sendai, Japan.
Hypertens Res. 2006 Jun;29(6):443-8. doi: 10.1291/hypres.29.443.
Hypertension frequently occurs in obese subjects. It has been reported that leptin and resistin induce endothelin-1 expression in vascular endothelial cells. Altered function of brain microvascular endothelial cells may be related to increased occurrences of stroke in hypertensive patients. In the present study, we therefore studied the effects of leptin and resistin on the expression of endothelin-1 and adrenomedullin in bovine brain microvascular endothelial cells. Northern blot analysis showed that leptin (10(-10)-10(-8) mol/l), resistin (10(-10)-10(-8) mol/l) or a combination of leptin and resistin (10(-8) mol/l for each) had no significant effects on the expression of endothelin-1 mRNA or adrenomedullin mRNA in cultured bovine brain microvascular endothelial cells. On the other hand, hypoxia induced, and tumor necrosis factor-alpha (10 ng/ml) decreased, the expression levels of endothelin-1 and adrenomedullin mRNAs, indicating that the bovine brain microvascular endothelial cells were able to respond to hypoxia and tumor necrosis factor-alpha. Consistent with the results of Northern blot analysis, immunoreactive endothelin and immunoreactive adrenomedullin concentrations in the medium were not significantly changed by the treatment with leptin, resistin, or a combination of leptin and resistin. The present study thus showed that neither leptin nor resistin affects the expression of endothelin-1 or adrenomedullin in bovine brain microvascular endothelial cells.
高血压在肥胖个体中经常出现。据报道，瘦素和抵抗素可诱导血管内皮细胞中内皮素-1的表达。脑微血管内皮细胞功能的改变可能与高血压患者中风发生率的增加有关。因此，在本研究中，我们研究了瘦素和抵抗素对牛脑微血管内皮细胞中内皮素-1和肾上腺髓质素表达的影响。Northern印迹分析表明，瘦素（10^(-10)-10^(-8) mol/l）、抵抗素（10^(-10)-10^(-8) mol/l）或瘦素与抵抗素的组合（每种10^(-8) mol/l）对培养的牛脑微血管内皮细胞中内皮素-1 mRNA或肾上腺髓质素mRNA的表达没有显著影响。另一方面，缺氧诱导，而肿瘤坏死因子-α（10 ng/ml）降低了内皮素-1和肾上腺髓质素mRNA的表达水平，表明牛脑微血管内皮细胞能够对缺氧和肿瘤坏死因子-α作出反应。与Northern印迹分析结果一致，用瘦素、抵抗素或瘦素与抵抗素的组合处理后，培养基中免疫反应性内皮素和免疫反应性肾上腺髓质素的浓度没有显著变化。因此，本研究表明，瘦素和抵抗素均不影响牛脑微血管内皮细胞中内皮素-1或肾上腺髓质素的表达。
