The effects of a hyperosmotic challenge in vivo on tissue composition of rat cardiac and skeletal muscle.
The effects of hyperosmotic stress under both acute and chronic conditions were investigated in two types of rat muscle tissue: cardiac and skeletal. Under acute conditions of a 4-h infusion, both types of muscle behaved as osmometers. However, under chronic hyperosmotic stress (several days), skeletal muscle behaved as predicted as an osmometer, but cardiac muscle did not. The levels of free amino acids in this tissue increased markedly--in particular, taurine. This phenomenon is discussed with respect to the capacity of this tissue for volume regulation.
Bedford
J J
JJ
Department of Physiology, University of Otago Medical School, Dunedin, New Zealand.
Leader
J P
JP
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001823:Body Composition / Q000187:drug effects*; D003964:Diaphragm / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005947:Glucose / Q000378:metabolism; D006321:Heart / Q000187:drug effects; D006982:Hypertonic Solutions / Q000494:pharmacology*; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012132:Respiratory Muscles / Q000187:drug effects / Q000378:metabolism*; D014508:Urea / Q000378:metabolism
D000596:Amino Acids; D006982:Hypertonic Solutions; D014508:Urea; D005947:Glucose