Effect of halothane administration on acetylcholinesterase activity in guinea-pig muscle and brain

The effect of halothane administration on the activity of acetylcholinester ase molecular forms was studied in diaphragm, extensor digitorum longus (ED L), and soleus muscles, and six regions of the brain (striatum, cerebellum, cortex, hippocampus, medulla-pons, midbrain) of guinea-pigs. Six days afte r the anaesthetic, the activity of the G4 form was significantly increased in all three muscles and the A12 form was significantly increased in EDL. T he G1 precursor form was significantly decreased in soleus. The G4 form was significantly increased in medulla-pons, and the G1 form was significantly decreased in hippocampus and midbrain. These findings show that halothane can have prolonged effects on acetylcholinesterase activity in both muscle and brain, and may have important implications for the use of halothane and other volatile anaesthetics in studies of the cholinergic system. (C) Crow n copyright 2000/DERA - published with the permission of the Controller of HMSO.