Effects of spaceflight on the attachment of tendons to bone in the hindlimb of the pregnant rat
Article first published online: 2 JAN 2005
Copyright © 2004 Wiley-Liss, Inc.
The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology
Volume 282A, Issue 2, pages 147–156, February 2005
How to Cite
Johnson, R. B., Tsao, A. K., John, K. R., Betcher, R. A., Tucci, M. A. and Benghuzzi, H. A. (2005), Effects of spaceflight on the attachment of tendons to bone in the hindlimb of the pregnant rat. Anat. Rec., 282A: 147–156. doi: 10.1002/ar.a.20139
- Issue published online: 24 JAN 2005
- Article first published online: 2 JAN 2005
- Manuscript Accepted: 18 AUG 2004
- Manuscript Received: 23 APR 2004
- National Aeronautics and Space Administration. Grant Number: NCC 2-863
- Sharpey's fibers
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. © 2004 Wiley-Liss, Inc.