Ahmed Z, Archer J R, Brown R A
Department of Plastic and Reconstructive Surgery, University College London Medical School, Rayne Institute, England.
Bone. 1995 Apr;16(4 Suppl):305S-310S. doi: 10.1016/8756-3282(95)00025-9.
The pattern of chondrocyte proliferation was studied in the proximal tibial growth plate of tich mice (gene symbol tch), a recessive mouse mutant, which is coisogenic with the A.TL strain. Specimens were qualitatively studied at time points of 2, 3, 4, 6, and 8 weeks of age by bromodeoxyuridine labeling of cell division and routine histology. At 2 weeks, when the lesion appeared as a full-width thickening of the growth plate, a greater proportion of cells appeared positively labeled in the proliferative zone. This concavity in the central portion of the growth plate became progressively more focal between 3 and 4 weeks to give a "tongue" of unresorbed, noncalcified cartilage in the central region of the tich growth plate. BrdUrd labeling indicated that the appearance of the cartilage tongue corresponded with increased cell division in the central region of the growth plate. At the same time, a "second" zone of cell division formed, within the zone of hypertrophy, such that labeled cells appeared to be set among chondrocytes with hypertrophic morphology. At stages after 4 weeks of age the focal feature disappeared as the growth plate returned to more normal morphology by maturity. It seems that this unique "second" zone of dividing cells may contribute to formation of an elongation of the nonresorbed tongue of cartilage. However, it is not likely to be the primary defect since growth plate changes were apparent at earlier stages.
在隐性小鼠突变体（基因符号tch）的胫骨近端生长板中研究了软骨细胞增殖模式，该突变体与A.TL品系同基因。通过细胞分裂的溴脱氧尿苷标记和常规组织学，在2、3、4、6和8周龄的时间点对标本进行定性研究。在2周龄时，当病变表现为生长板全宽增厚时，增殖区中出现阳性标记的细胞比例更高。在3至4周龄之间，生长板中央部分的这种凹陷逐渐变得更加局限，从而在tich生长板的中央区域形成一个未吸收、未钙化软骨的“舌状”结构。BrdUrd标记表明，软骨舌的出现与生长板中央区域细胞分裂增加相对应。与此同时，在肥大区内形成了一个“第二”细胞分裂区，使得标记细胞似乎分布在具有肥大形态的软骨细胞之间。在4周龄后的阶段，随着生长板在成熟时恢复到更正常的形态，局灶性特征消失。似乎这个独特的分裂细胞“第二”区可能有助于形成未吸收软骨舌的延长。然而，它不太可能是主要缺陷，因为生长板的变化在更早阶段就很明显。
