Lack of chlorpromazine effect on skeletal muscle metabolism after ischemia and a short reperfusion period.
The great resistance of muscle to ischemia was used to study blood flow-dependent phenomena produced by anesthetic drugs in this condition. A short reperfusion period was used in order to favor metabolic changes indicative of an effect of chlorpromazine (CPZ) on blood flow. Gracilis muscles of dogs were submitted to 5 h of ischemia and 30 min of reperfusion. CPZ-treated animals were injected I.V. (2 mg/kg) 10 min before the beginning of ischemia. Biopsies provided the material for tissue measurements. Lactate content and pH were determined in blood samples collected from a muscle efferent vein. In both the CPZ-treated and nontreated groups, ischemia induced a decline in muscle glycogen content, with a corresponding increase in muscle lactate and a decrease in mitochondrial respiratory control ratio. After 30 min of reperfusion, tissue levels of lactate did not attain preischemic values but showed a clear decline in the two experimental groups, evidencing the reversible state of the muscle. All other metabolic parameters remained unchanged. Mitochondrial respiratory control remained functional during ischemia and reperfusion. Blood pH displayed similar changes in both groups. There was no metabolic indication that the drug affected blood flow during early reperfusion and/or of a greater sensitivity of muscle endothelial cells to anesthetic drugs.
Piccinato
Carlos E
CE
Department of Surgery and Anatomy, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. cepiccin@fmrp.usp.br
Salles Roselino
José E
JE
Massuda
Carlos A
CA
Cherri
Jesualdo
J
D000818:Animals; D002746:Chlorpromazine / Q000494:pharmacology*; D004195:Disease Models, Animal; D004285:Dogs; D006003:Glycogen / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007511:Ischemia / Q000188:drug therapy* / Q000628:therapy; D007773:Lactates / Q000378:metabolism; D008931:Mitochondria, Muscle / Q000187:drug effects / Q000378:metabolism*; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000378:metabolism; D009142:Musculoskeletal Physiological Phenomena; D012016:Reference Values; D015427:Reperfusion Injury / Q000378:metabolism*
D007773:Lactates; D006003:Glycogen; D002746:Chlorpromazine