Imai H, Connell C E, Lee K T, Kim D N, Thomas W A
Exp Mol Pathol. 1985 Jun;42(3):377-88. doi: 10.1016/0014-4800(85)90087-5.
Hyperlipidemic diet-induced atherosclerotic lesions show a predilection for locating at the site of normal collections of intimal cells in the swine abdominal aorta. This implies that preexisting intimal cell masses (ICM) evolve into early diet-induced lesions. This study characterizes in detail the distal abdominal aortic ICM of young normal swine as a basis for a better understanding of lesion development. Seventeen male Yorkshire swine were used, from neonates to 20 weeks of age. Only three of six neonates showed multilayered ICM, the remaining three showed scattered individual cells or a single layer of cells. All older swine had multilayered ICM at a predictable ventral site corresponding to Evans blue in vivo staining. The majority of cells counted by electron microscopy were smooth muscle (89 to 94%), the remaining were macrophages (1 to 8%) and poorly differentiated cells (3 to 5%). Weanling and older swine showed high proportions of contractile smooth muscle cells. Ergastoplasm-rich smooth muscle cells comprised nearly half of the neonatal population. Stainable lipids were demonstrable in 20-week-olds, but not in younger swine. No foam cells were seen, but cells containing a few droplets totaled 2%; macrophages comprised a high proportion of these. Pyknotic dead cells were rare, being found in the neonate and 20-week-old swine. Mitoses were observed in two ergastoplasm-rich smooth muscle cells in the neonate and one each in contractile smooth muscle cells of a 14- and a 20-week-old swine. Saddlebag-shaped, atypical-appearing cells were present in all age groups, involving all three cell types, and ranging from 1 to 3%. These represented either bridged nuclei and cytoplasm or more likely artefactual distortion of relatively normal cells.
高脂饮食诱导的动脉粥样硬化病变倾向于出现在猪腹主动脉内膜细胞正常聚集的部位。这意味着预先存在的内膜细胞团块（ICM）会演变成早期饮食诱导的病变。本研究详细描述了年轻正常猪腹主动脉远端的ICM，以便更好地理解病变发展。使用了17只雄性约克夏猪，年龄从新生仔猪到20周龄。6只新生仔猪中只有3只显示出多层ICM，其余3只显示单个散在细胞或单层细胞。所有年龄较大的猪在与体内伊文思蓝染色相对应的可预测腹侧部位都有多层ICM。通过电子显微镜计数，大多数细胞是平滑肌细胞（89%至94%），其余为巨噬细胞（1%至8%）和低分化细胞（3%至5%）。断奶仔猪和年龄较大的猪显示出高比例的收缩性平滑肌细胞。富含内质网的平滑肌细胞占新生仔猪总数的近一半。在20周龄的猪中可检测到可染色脂质，但在较年轻的猪中未检测到。未观察到泡沫细胞，但含有少量脂滴的细胞占2%；其中巨噬细胞占很大比例。固缩死亡细胞很少见，仅在新生仔猪和20周龄的猪中发现。在新生仔猪的2个富含内质网的平滑肌细胞中观察到有丝分裂，在14周龄和20周龄猪的收缩性平滑肌细胞中各观察到1个有丝分裂。所有年龄组均存在鞍袋状、外观异常的细胞，涉及所有三种细胞类型，比例为1%至3%。这些细胞要么是桥接的细胞核和细胞质，要么更可能是相对正常细胞的人为扭曲。
