Wronski T J, Li M, Shen Y, Miller S C, Bowman B M, Kostenuik P, Halloran B P
Department of Physiological Sciences, University of Florida, Gainesville, Florida 32610, USA.
J Appl Physiol (1985). 1998 Jul;85(1):279-85. doi: 10.1152/jappl.1998.85.1.279.
As part of an experiment to study the role of corticosteroids in bone changes during spaceflight, male Sprague-Dawley rats (6 wk old, 165 g body weight) were placed in orbit for 17 days, in groups of six, in animal-enclosure modules (AEMs) aboard the space shuttle Columbia (STS-78). Control rats were group housed in a similar manner in ground-based AEMs or standard vivarium cages. Adrenal hypertrophy occurred in flight rats, but bone histomorphometric analyses revealed a lack of significant changes in bone mass and bone formation in these animals. Cancellous bone volume and osteoblast surface in the proximal tibial metaphysis were nearly the same in flight and ground-based rats. Normal levels of cancellous bone mass and bone formation were also detected in the lumbar vertebrae and femoral necks of flight rats. In the tibial diaphysis, periosteal bone formation rate was found to be identical in flight and ground-based rats. The results indicate that, under conditions of group housing in AEMs, spaceflight has minimal effects on bone mass and bone formation in rapidly growing rats. These findings emphasize the need to investigate the importance of rat age, strain, and especially housing conditions for studies of the skeletal effects of spaceflight.
作为一项研究皮质类固醇在太空飞行期间骨骼变化中作用的实验的一部分，雄性斯普拉格-道利大鼠（6周龄，体重165克）以每组6只的方式被安置在哥伦比亚号航天飞机（STS-78）上的动物饲养舱模块（AEM）中，在轨道上停留17天。对照大鼠以类似方式成群饲养在地面AEM或标准饲养笼中。飞行大鼠出现肾上腺肥大，但骨组织形态计量学分析显示这些动物的骨量和骨形成没有显著变化。飞行大鼠和地面大鼠胫骨近端干骺端的松质骨体积和成骨细胞表面几乎相同。在飞行大鼠的腰椎和股骨颈也检测到正常水平的松质骨量和骨形成。在胫骨骨干，飞行大鼠和地面大鼠的骨膜骨形成率相同。结果表明，在AEM中成群饲养的条件下，太空飞行对快速生长大鼠的骨量和骨形成影响极小。这些发现强调了在研究太空飞行对骨骼的影响时，有必要研究大鼠年龄、品系，尤其是饲养条件的重要性。
