Cardiac morphology after conditions of microgravity during COSMOS 2044

J Appl Physiol (1985). 1992 Aug;73(2 Suppl):94S-100S. doi: 10.1152/jappl.1992.73.2.S94.


Light- and electron-microscopic studies were performed on cardiac muscle from rats flown on COS-MOS 2044 and from four control groups. Average cross-sectional area of myofibers was measured by video analysis of the light-microscopic images of papillary and ventricular muscle samples from all animals. This cross-sectional area was significantly decreased in flight rats (P = 0.03) compared with synchronous controls. Additional findings at the electron-microscopic level consistent with this atrophy were obtained by stereological analysis and optical diffraction analysis of papillary muscle samples. Slightly higher mitochondrial volume density values and mitochondria-to-myofibril ratios as well as normal A-band spacings (d1,0) and Z-band spacings of myofibrils were observed in the tail-suspension and flight groups. General morphological features similar to those in ventricular samples from the previous COSMOS 1887 flight were observed.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Heart / anatomy & histology
  • Heart / physiology*
  • Male
  • Microscopy, Electron
  • Microtubules / metabolism
  • Mitochondria, Heart / metabolism
  • Myocardium / metabolism
  • Myocardium / ultrastructure
  • Myofibrils / metabolism
  • Rats
  • Rats, Inbred Strains
  • Space Flight*
  • Weightlessness / adverse effects*