Tissue specific changes in protein synthesis rates in vivo during
anoxia in crucian carp.
Smith, Richard W., Dominic F. Houlihan, G[diaeresis]oran E. Nilsson,
and James G. Brechin.
Department of Zoology, University of Aberdeen, Aberdeen, AB9 2TN,
Scotland, UK. Department of Limnology, Uppsala University,
Norbygv[umlaut]agen 20, S-752 36 Uppsala, Sweden
APStracts 3:0168R, 1996.
Mechanisms of anoxia tolerance were investigated in crucian carp.
Rates of protein synthesis were calculated in selected tissues of
normoxic and anoxic animals. Exposure to 48h anoxia resulted in a
significant reduction in protein synthesis in the liver (>95%),
heart (53%), and red and white muscle (52 and 56%, respectively)
whereas brain protein synthesis rates were unaffected. Seven days of
anoxia produced similar results. After 24 h recovery from a 48 h
anoxic period protein synthesis rates had virtually returned to
normoxic values. The effect of anoxia on the amount of RNA (relative
to protein) varied depending on the tissue and also the length of
exposure (except in the brain, where it was consistently reduced).
However the effect on RNA translational efficiency was purely tissue
specific (ie independent of exposure time); and was unaffected in the
heart, reduced in the liver, red and white muscle and increased in
the brain. Down regulation of protein synthesis on a tissue specific
basis appears to be a significant mechanism for energy conservation
as well as maintaining neural function; thus promoting survival,
during anoxia.
Received 14 August 1995; accepted in final form 22 March 1996.
APS Manuscript Number R509-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 8 May 96