In-flight and postflight changes in skeletal muscles of SLS-1 and SLS-2 spaceflown rats. J Appl Physiol (1985) 1996 Jul;81(1):133-44
Date
07/01/1996Pubmed ID
8828655DOI
10.1152/jappl.1996.81.1.133Scopus ID
2-s2.0-9344226776 (requires institutional sign-in at Scopus site) 82 CitationsAbstract
Spacelab Life Sciences-1 and -2 provided skeletal muscles from rats dissected in flight for the first time and 2 h to 14 days postflight. The muscles permitted the distinguishing of primary adaptations to microgravity from secondary reloading-induced alterations. In microgravity, rats adopted bipedal forelimb locomotion with the hindlimbs relegated to grasping activities. On landing day, body posture was abnormally low and walking was stilted at a rate one-third of normal. The adductor longus (AL) and soleus muscles exhibited decreased myofiber areas that did not recover 14 days postflight. Doubling of the nonmyofiber area indicated interstitial edema in AL muscles 2.3 h postflight. Solei did not manifest edema postflight, and neither muscle showed edema in flight. Sarcomere eccentric contraction-like lesions were detected in 2.6% of AL myofibers 4.5 h postflight; lesions were absent earlier postflight and in flight. At 9 days postflight, these lesions were repaired but regenerating AL myofibers were present, which suggests that myofiber necrosis occurred 1-2 days postflight. These studies demonstrate that muscle atrophy occurs in microgravity, whereas interstitial edema and sarcomere lesions are postflight phenomena.
Author List
Riley DA, Ellis S, Slocum GR, Sedlak FR, Bain JL, Krippendorf BB, Lehman CT, Macias MY, Thompson JL, Vijayan K, De Bruin JAAuthor
Beth B. Krippendorf PhD Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adaptation, PhysiologicalAnimals
Atrophy
Connective Tissue
Histocytochemistry
Male
Mast Cells
Movement
Muscle, Skeletal
Organelles
Posture
Rats
Rats, Sprague-Dawley
Sarcomeres
Space Flight
Weightlessness
