The influence of different body temperatures on the epileptiform discharges induced in hippocampus by local microinjections of leu-enkephalin was studied in rats. In the absence of enkephalin, changes in body temperature by either cooling or heating induced epileptiform discharges that disappeared after temperature stabilization. The epileptiform episode induced by enkephalin microinjections was of longer duration at temperatures below normal (29-30°C). At body temperatures above normal (39-40°C) the epileptiform discharge was less intense and of shorter duration. In vitro testing led to parallel results: the destruction of enkephalin by the brain tissue was faster at higher temperatures. It is proposed that in conditions of hyperthermia enkephalin has a weaker activity due to acceleration of the activity of peptidases involved in its breakdown.
|Number of pages
|Electroencephalography and Clinical Neurophysiology
|Published - Dec 1981