Teupser D, Thiery J, Haas U, Stein O, Stein Y, Seidel D
Institute of Clinical Chemistry, University Hospital Grosshadern, Munich, Germany.
Atherosclerosis. 1997 Feb 10;128(2):157-64. doi: 10.1016/s0021-9150(96)05997-7.
Recently we have described two strains of rabbits, one with a low (LAR) the other with a high (HAR) atherosclerotic response to dietary hypercholesterolemia. After feeding a cholesterol diet for 12 weeks, HAR rabbits developed atherosclerotic lesions throughout the entire aortic arch and thoracic aorta. In contrast, the lesions in LAR rabbits were mainly confined to the aortic arch. Presently we studied the cellular composition and expression of vascular cell adhesion molecule-1 (VCAM-1) in aortic lesions and in the uninvolved aorta of cholesterol fed HAR and LAR rabbits. Plasma cholesterol levels were 1106 +/- 160 and 1152 +/- 232 mg/dl in HAR and LAR rabbits, respectively, and the distribution of cholesterol among the lipoprotein fractions was similar after 16 weeks of 0.5% cholesterol feeding. In analogy to our previous findings, in the HAR rabbits more than 70% of the aorta (aortic arch and thoracic aorta) was covered with lesions, whereas in the LAR rabbits the lesions were seen in the aortic arch only and covered less than 20% of the total aortic surface. The cellular composition of aortic lesions was defined using specific antibodies to macrophages, smooth muscle cells, T lymphocytes and Ia expressing cells. All these cellular elements were represented in lesions derived from both strains of rabbits. We also examined the expression of VCAM-1 in the aorta of HAR and LAR rabbits after cholesterol feeding. In the aortic arch, a positive reaction for VCAM-1 was found in lesions from both strains of rabbits. The staining was seen in the endothelium and within the lesion, mainly at its base. In the thoracic aorta of HAR rabbits, VCAM-1 expression was found in all lesions examined. In the thoracic aorta of LAR rabbits, VCAM-1 expression was seen in an occasional very small lesion found at the ostium of an intercostal artery. These results show that the VCAM-1 gene is expressed in the LAR rabbits, but its induction is perhaps attenuated.
最近我们描述了两种兔品系，一种对饮食性高胆固醇血症的动脉粥样硬化反应较低（低反应兔，LAR），另一种反应较高（高反应兔，HAR）。在给予胆固醇饮食12周后，HAR兔在整个主动脉弓和胸主动脉出现了动脉粥样硬化病变。相比之下，LAR兔的病变主要局限于主动脉弓。目前我们研究了给予胆固醇的HAR和LAR兔主动脉病变及未受累主动脉中血管细胞粘附分子-1（VCAM-1）的细胞组成和表达。HAR兔和LAR兔的血浆胆固醇水平分别为1106±160和1152±232mg/dl，在给予0.5%胆固醇饮食16周后，胆固醇在脂蛋白组分中的分布相似。与我们之前的研究结果类似，在HAR兔中，超过70%的主动脉（主动脉弓和胸主动脉）被病变覆盖，而在LAR兔中，病变仅见于主动脉弓，覆盖的主动脉总面积不到20%。使用针对巨噬细胞、平滑肌细胞、T淋巴细胞和Ia表达细胞的特异性抗体来确定主动脉病变的细胞组成。所有这些细胞成分在两种兔品系的病变中均有体现。我们还检测了给予胆固醇后HAR和LAR兔主动脉中VCAM-1的表达。在主动脉弓，两种兔品系的病变中均发现VCAM-1呈阳性反应。染色见于内皮和病变内，主要在病变底部。在HAR兔的胸主动脉中，所有检测的病变中均发现有VCAM-1表达。在LAR兔的胸主动脉中，仅在肋间动脉开口处偶尔发现的一个非常小的病变中可见VCAM-1表达。这些结果表明，VCAM-1基因在LAR兔中表达，但可能其诱导作用减弱。
