Pravenec M, Landa V, Zídek V, Musilová A, Kazdová L, Qi N, Wang J, St Lezin E, Kurtz T W
Institute of Physiology, Academy of Sciences of the Czech Republic, Vídenská 1083, 142 20 Prague 4, Czech Republic.
Physiol Res. 2003;52(6):681-8.
Spontaneously hypertensive rats (SHR/NIH strain) harbor a deletion variant in the Cd36 fatty acid transporter and display defective fatty acid metabolism, insulin resistance and hypertension. Transgenic rescue of Cd36 in SHR ameliorates insulin resistance and improves dyslipidemia. However, the role of Cd36 in blood pressure regulation remains controversial due to inconsistent blood pressure effects that were observed with transgenic expression of Cd36 on the SHR background. In the current studies, we developed two new SHR transgenic lines, which express wild type Cd36 under the control of the universal Ef-1 alpha promoter, and examined the effects of transgenic expression of wild type Cd36 on selected metabolic and cardiovascular phenotypes. Transgenic expression of Cd36 in the new lines was associated with significantly decreased serum fatty acids, amelioration of insulin resistance and glucose intolerance but failed to induce any consistent changes in blood pressure as measured by radiotelemetry. The current findings confirm the genetic association of defective Cd36 with disordered insulin action and fatty acid metabolism in the SHR/NIH strain and suggest that Cd36 is linked to other gene(s) on rat chromosome 4 that regulate blood pressure.
自发性高血压大鼠(SHR/NIH品系)在Cd36脂肪酸转运体中存在一个缺失变异体,表现出脂肪酸代谢缺陷、胰岛素抵抗和高血压。在SHR中对Cd36进行转基因挽救可改善胰岛素抵抗并改善血脂异常。然而,由于在SHR背景下通过Cd36转基因表达观察到的血压效应不一致,Cd36在血压调节中的作用仍存在争议。在当前研究中,我们构建了两个新的SHR转基因品系,它们在通用的Ef-1α启动子控制下表达野生型Cd36,并研究了野生型Cd36转基因表达对选定的代谢和心血管表型的影响。新的品系中Cd36的转基因表达与血清脂肪酸显著降低、胰岛素抵抗和葡萄糖耐量改善相关,但通过无线电遥测测量未发现血压有任何一致的变化。当前研究结果证实了SHR/NIH品系中Cd36缺陷与胰岛素作用紊乱和脂肪酸代谢之间的遗传关联,并表明Cd36与大鼠4号染色体上其他调节血压的基因有关。