Matsumoto A, Taguchi H, Hisada Y
Department of Dental Pharmacology, School of Dentistry, Hokkaido University, Japan.
Toxicol In Vitro. 1991;5(1):51-62. doi: 10.1016/0887-2333(91)90047-h.
The effect of a low-Ca environment on neonatal rat femora was investigated in vitro. One-day-old Wistar strain rat femora were cultured in either control (7.47 +/- 0.18 mg Ca/dl) or low-Ca (1.19 +/- 0.08 mg Ca/dl) media. Growth and development were greater in femora in the low-Ca group than in the control group. The femur head was larger in the low-Ca group than in the control group. Roentgenography showed that the total length and head length of femora increased with time in both groups. Calcification of the diaphyseal bone was lower in the low-Ca group than in the control group, while the cartilage cell zone in the femur head widened more in the low-Ca group. The hypertrophic cartilage cell zone widened particularly in the low-Ca group. Alkaline phosphatase activity, cell proliferation and chondroitin sulphate synthesis activity were higher in the low-Ca group, and the protein content increased more in the low-Ca group. However, collagen synthesis was lower in the low-Ca group. In dead bone, chondroitin sulphate synthesis was not observed in either the control or the low-Ca group. The results suggest that cell proliferation and chondroitin sulphate synthesis are mediated and enhanced and that collagen synthesis is weak when organs are placed in a low-Ca environment.
体外研究了低钙环境对新生大鼠股骨的影响。将1日龄Wistar品系大鼠的股骨培养于对照培养基（钙含量7.47±0.18mg/dl）或低钙培养基（钙含量1.19±0.08mg/dl）中。低钙组股骨的生长发育比对照组更显著。低钙组的股骨头比对照组大。X线摄影显示，两组股骨的总长度和头部长度均随时间增加。低钙组骨干骨的钙化程度低于对照组，而低钙组股骨头的软骨细胞区增宽更明显。低钙组肥大软骨细胞区尤其增宽。低钙组的碱性磷酸酶活性、细胞增殖和硫酸软骨素合成活性较高，蛋白质含量增加也更多。然而，低钙组的胶原蛋白合成较低。在死骨中，对照组和低钙组均未观察到硫酸软骨素合成。结果表明，当器官置于低钙环境中时，细胞增殖和硫酸软骨素合成受到介导并增强，而胶原蛋白合成较弱。
