Johnson Roger B, Tsao Audrey K, St John Kenneth R, Betcher Russel A, Tucci Michelle A, Benghuzzi Hamed A
School of Dentistry, University of Mississippi Medical Center, Jackson, Mississippi 39215, USA.
Anat Rec A Discov Mol Cell Evol Biol. 2005 Feb;282(2):147-56. doi: 10.1002/ar.a.20139.
The objective of this study was to determine the effects of spaceflight on the structure of the tendon-bone junction (TBJ). Pregnant rats either flew in the space shuttle Atlantis (flight group; F) or were exposed to simulated launch and landing protocols (synchronous control group; SC) during days 9-19 of pregnancy. Following birth of their pups, maternal hindlimbs were studied using scanning electron and light microscopic histomophometric techniques. The tibial and calcaneal tuberosities, the fibular head, and the tibia-fibula junction were studied. Myofiber density and cross-sectional area of the quadratus femoris and soleus muscles and diameters of the calcaneal and patellar tendons were also evaluated. Cortical erosion was significantly greater at the tibial tuberosity and the fibular head in F animals compared to SC animals (P < 0.001). Sharpey fiber density was significantly less at the tibial tuberosity and fibular head in F animals compared to SC animals (P < 0.001). The myofiber area of both the soleus and quadratus femoris muscles and the diameters of both calcaneal and patellar tendons were significantly less in F compared to SC rats (P < 0.05). Our data illustrate that the TBJ morphology is affected by spaceflight at the attachment sites of the soleus and quadratus femoris muscles in pregnant animals, which could adversely affect their physical properties. These atrophic TBJ changes could have resulted from atrophy of the adjacent muscles and their tendons. Atrophic changes in the structure of the TBJ could predispose an animal to injury following spaceflight, when normal gravity conditions are reestablished.
本研究的目的是确定太空飞行对肌腱-骨连接（TBJ）结构的影响。怀孕大鼠在妊娠第9至19天期间，要么搭乘亚特兰蒂斯号航天飞机飞行（飞行组；F），要么接受模拟发射和着陆方案（同步对照组；SC）。幼崽出生后，使用扫描电子显微镜和光学显微镜组织形态计量学技术研究母鼠后肢。研究了胫骨结节、跟骨结节、腓骨头以及胫腓关节。还评估了股四头肌和比目鱼肌的肌纤维密度和横截面积，以及跟腱和髌腱的直径。与SC组动物相比，F组动物的胫骨结节和腓骨头处的皮质侵蚀明显更严重（P < 0.001）。与SC组动物相比，F组动物的胫骨结节和腓骨头处的沙比纤维密度明显更低（P < 0.001）。与SC组大鼠相比，F组大鼠的比目鱼肌和股四头肌的肌纤维面积以及跟腱和髌腱的直径均明显更小（P < 0.05）。我们的数据表明，太空飞行会影响怀孕动物比目鱼肌和股四头肌附着部位的TBJ形态，这可能会对其物理特性产生不利影响。这些萎缩性的TBJ变化可能是由相邻肌肉及其肌腱的萎缩导致的。当重新建立正常重力条件时，TBJ结构的萎缩性变化可能使动物在太空飞行后更容易受伤。
