Skip to page content Mission Information


Histological Effects of Microgravity on Rat Body Wall Musculature (9303017)
Principal Investigator
Research Area:
Developmental biology
Muscle physiology
Species Studied
Scientific Name: Rattus norvegicus Species: Rat Strain: Sprague-Dawley


The purpose of this study was to examine the effects of four variables on histological properties of three muscles from the rat body wall. The muscles examined were the rectus abdominis (RA), transversus abdominis (TA), and external oblique (EO). These muscles function in both locomotion and in raising intra-abdominal pressure to expel material, including pups at birth, from the body cavity. The variables examined were: 1) gestation, 2) animal caging, 3) the effect of a midline laparotomy performed early in gestation to determine fetus numbers, 4) exposure to spaceflight.

++ -- View more

Fejtek M, Wassersug RJ: Effects of laparotomy, cage type, gestation period and spaceflight on abdominal muscles of pregnant rodents. J Exp Zool. 1999 Aug 1;284(3):252-64.

Fejtek M, Wassersug RJ: Survey of studies on how spaceflight affects rodent skeletal muscle. Adv Space Biol Med. 1999;7:1-30.

Rectus abdominis
Myosin heavy chains (MHC)
Cesarean section

Data Information
Data Availability
Archive is complete. All data sets are on the Web site.
Data Sets + View data.
NASA GeneLab Data

Properties, Fiber, abdominal rectus, muscle, rat, Histo-, immuno-chemistry, microscopy
Properties, Fiber, diaphragm, muscle, rat, Histo-, immuno-chemistry, microscopy
Properties, Fiber, external oblique, muscle, rat, Histo-, immuno-chemistry, microscopy
Properties, Fiber, internal oblique, muscle, rat, Histo-, immuno-chemistry, microscopy
Size, diameter, Fiber, abdominal rectus, muscle, rat: Image analysis.
++ -- View more

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
STS-70 07/13/1995 07/22/1995 9 days

Additional Information
Managing NASA Center
Ames Research Center (ARC)
Responsible NASA Representative
Ames Research Center LSDA Level 3
Project Manager: Martha Del Alto
Institutional Support
National Aeronautics and Space Administration (NASA)
Protocol / Approach
Delayed synchronous control
Vivarium control
Proposal Date
Proposal Source