Oxlund H, Ejersted C, Andreassen T T, Tørring O, Nilsson M H
Department of Connective Tissue Biology, University of Aarhus, Denmark.
Calcif Tissue Int. 1993 Dec;53(6):394-9.
The anabolic effect of intermittent treatment with parathyroid hormone (PTH) on cortical bone was investigated. Groups of rats were injected with human PTH (1-34) or PTH (1-84), 1.1, 3.3, 10, and 30 nmol/kg/day for 30 days. A dose-related increase in bone formation rate at the femoral middiaphysis was found at both the periosteum and the endosteum and also an increase in bone mass, with no change in the bone lengths or body weight gain of the rats. The highest mineral apposition rate, as analyzed by tetracycline labeling, was found at the periosteal postero-medial aspect and at the endosteal anterior aspect. This pattern of bone modeling was also found in the PTH-treated animals, although more and more areas were included in bone mineral apposition. The PTH treatments did not change the porosity of the cortical bone nor the concentration and biochemical stability of the collagen. The highest doses of PTH resulted in a slight reduction in the ash concentration of cortical bone. No differences were found between the effects of PTH (1-34) and PTH (1-84) on bone formation rate, bone mass, porosity, and biochemical parameters. Consequently, intermittent treatment with PTH increased the formation of cortical bone dose dependently, at both the periosteum and the endosteum and increased the bone mass of these growing rats, with no change in the body weight gain or femoral growth rate compared with the control animals. The responses of the cortical bone modeling were increased by the PTH treatments without changing its direction or pattern.
研究了甲状旁腺激素（PTH）间歇治疗对皮质骨的合成代谢作用。将大鼠分组，分别注射人PTH（1-34）或PTH（1-84），剂量为1.1、3.3、10和30 nmol/kg/天，持续30天。在股骨中骨干的骨膜和内膜处均发现骨形成率呈剂量相关增加，骨量也增加，而大鼠的骨长度或体重增加无变化。通过四环素标记分析发现，最高的矿物质沉积率出现在骨膜后内侧和内膜前侧。在PTH治疗的动物中也发现了这种骨重塑模式，尽管骨矿物质沉积的区域越来越多。PTH治疗并未改变皮质骨的孔隙率，也未改变胶原蛋白的浓度和生化稳定性。最高剂量的PTH导致皮质骨灰分浓度略有降低。PTH（1-34）和PTH（1-84）对骨形成率、骨量、孔隙率和生化参数的影响未发现差异。因此，与对照动物相比，PTH间歇治疗可使皮质骨在骨膜和内膜处的形成呈剂量依赖性增加，并增加这些生长中大鼠的骨量，而体重增加或股骨生长速率无变化。PTH治疗增加了皮质骨重塑的反应，但未改变其方向或模式。
