Electrophysiological Studies on the Effect of Methylguanidine (MG) on Central Nervous System and Peripheral Nervous System Activity

Abstract

The effect of MG on central and peripheral nervous system activity was investigated electrophysiologically in the rabbit and the following observed,
1) The threshold of arousal reaction and evoked m ascular discharge due to stimulation of the brain stem reticular formation slightly rises with administration of MG.
2) The frequency of spontaneous unit discharge of the brain stem reticular formation shows a trend to slightly decrease with administration of MG.
3) The threshold of evoked mascular discharge of the fore and hind limbs due to stimulation of the cerebral cortex rises with administration of MG.
4) The threshold of evoked muscular discharge of the f ore and hind limbs due to stimulation of the hippocampus slightly drops with the administration of a small amount of MG but recovers and slightly rises on increasing the quantity of MG.
5) The amplitude of the afferent average evoked poten tial appearing in the cerebral cortex decreases in general but the amplitude of N₃ shows a trend to increase markedly.
6) The amplitude of the afferent average evoked potential appearing in the hippocampus is inhibited by the administration of MG.
7) The amplitude of the nociceptiv e reflex muscular discharge is decreased by the administration of MG.
8) The am plitude of the M-H wave is decreased by the administration of MG.
9) Spontaneous discharge of the sympathetic nerve is intensified by the adm inistration of MG.
10) The blood flow volume of the common carotid artery shows a trend to decrease with administration of MG.
11) Intestinal movement is markedly inhibited with administration of MG.
12) MV is slightly inhibited by the administration of a small amount of MG but gradually recovers and increases on increasing the quantity of MG.
13) PPR_6,7,8 increases on increasing the quantity of MG.