Breur G J, VanEnkevort B A, Farnum C E, Wilsman N J
Department of Comparative Biosciences, University of Wisconsin, Madison.
J Orthop Res. 1991 May;9(3):348-59. doi: 10.1002/jor.1100090306.
In this study, we tested the hypothesis that hypertrophic cell volume varies directly with the rate of longitudinal bone growth. The volume of hypertrophic chondrocytes (using stereological techniques) and longitudinal bone growth per 24 h (using oxytetracycline labeling techniques) were measured in the proximal and distal radial growth plates and the proximal and distal tibial growth plates of 21- and 35-day-old hooded rats and 21- and 35-day-old Yucatan pigs. We demonstrated a high coefficient of correlation (rats 0.98, pigs 0.83) between the final volume of hypertrophic chondrocytes and the rate of longitudinal bone growth over a wide range of growth rates and volumes of hypertrophic chondrocytes. In addition, we demonstrated a positive linear relationship between the rate of longitudinal bone growth and the final volume of hypertrophic chondrocytes. The slope of the regression line was different for rats than for pigs. The relationship was independent of the location of the growth plate in the animal and the age of the animal. The data suggest that mechanisms regulating volume changes in hypertrophic chondrocytes may exist and that chondrocytic volume increase is a major determinant of the rate of longitudinal bone growth. However, the relative contribution of cellular hypertrophy to longitudinal bone growth may be different in rats than in pigs.
在本研究中，我们验证了一个假设，即肥大细胞体积与纵向骨生长速率直接相关。使用体视学技术测量了21日龄和35日龄带帽大鼠以及21日龄和35日龄尤卡坦猪的桡骨近端和远端生长板以及胫骨近端和远端生长板中肥大软骨细胞的体积（使用体视学技术）和每24小时的纵向骨生长（使用土霉素标记技术）。我们证明，在肥大软骨细胞的广泛生长速率和体积范围内，肥大软骨细胞的最终体积与纵向骨生长速率之间存在高度相关性（大鼠为0.98，猪为0.83）。此外，我们还证明了纵向骨生长速率与肥大软骨细胞的最终体积之间存在正线性关系。大鼠的回归线斜率与猪不同。这种关系与生长板在动物体内的位置以及动物的年龄无关。数据表明，可能存在调节肥大软骨细胞体积变化的机制，并且软骨细胞体积增加是纵向骨生长速率的主要决定因素。然而，细胞肥大对纵向骨生长的相对贡献在大鼠和猪中可能有所不同。
