The effect of haloperidol, spiperone and dantrolene on the concentrations of creatine phosphate, ATP and lactate in brain and skeletal muscle of the rat during halothane anesthesia.

The concentrations of creatine phosphate, ATP and lactate were measured in the brain and skeletal muscle of rats under halothane anesthesia (1 to 2% in oxygen) and in animals either premedicated with haloperidol or spiperone (200 mg kg-1 and 2 mg kg-1) or treated with dantrolene (860 mg kg-1). Haloperidol and spiperone had no effect on ATP or lactate in skeletal muscle, but caused more than a 30% increase in the concentration of creatine phosphate (p less than 0.01). With dantrolene, an 80% increase in creatine phosphate (p less than 0.0001) and a significant decrease in lactate (p less than 0.0001) were found. Haloperidol caused a significant decrease in brain creatine phosphate concentration (p less than 0.05) while at a dosage of 2 mg kg-1, the ATP concentration was higher (p less than 0.05). Spiperone (2 mg kg-1) caused a 19% increase in creatine phosphate (p less than 0.005) as well as a significant decrease in lactate (p less than 0.005). Dantrolene had no significant effect on the concentration of any brain metabolite. Our results indicate that the effect of anesthetics on the concentration of energy metabolites in tissues can be influenced by drug treatment, which may have implications in the choice of an anesthetic regimen to be used in tissue harvesting.