Seifert M F, Popoff S N, Marks S C
Department of Anatomy, University of South Dakota School of Medicine, Vermillion 57069.
Am J Anat. 1988 Oct;183(2):158-65. doi: 10.1002/aja.1001830206.
The toothless (tl) rat is a nonlethal osteopetrotic mutation characterized by the presence of few osteoclasts and the failure to be cured by bone-marrow transplantation. We examined the skeletal biology of tl rats and normal littermates up to 6 weeks after birth. Osteoclasts in tl rats were small, reduced 25-fold in number, and had greatly reduced concentrations of acid hydrolases. Bone shape internally and externally reflected reduced bone resorption, and tl rats were hypophosphatemic and mildly hypocalcemic at 2 weeks. These data indicate that the basic defect in tl rats is one of differentiation of osteoclasts and, coupled with the observation that normal bone-marrow cells cannot develop into osteoclasts in the tl skeleton, suggest that the defect lies in the skeletal micro-environment.
无齿（tl）大鼠是一种非致死性骨石化突变体，其特征是破骨细胞数量少，且不能通过骨髓移植治愈。我们研究了出生后6周内tl大鼠和正常同窝仔鼠的骨骼生物学。tl大鼠的破骨细胞体积小，数量减少了25倍，酸性水解酶浓度也大大降低。骨骼的内部和外部形状反映出骨吸收减少，tl大鼠在2周时出现低磷血症和轻度低钙血症。这些数据表明，tl大鼠的基本缺陷是破骨细胞分化异常，再加上正常骨髓细胞在tl大鼠骨骼中不能发育成破骨细胞这一观察结果，提示缺陷在于骨骼微环境。
