Reserpine and oxotremorine tremor as well as the effect of amantadine on the tremor activity produced by both drugs were studied in rats with respect to changes in alpha and gamma motor activity.
The tremor activity elicited by reserpine (10 mg/kg i.v.) is maintained by the alpha motoneurones, whereas the tremor activity developing during an infusion of oxotremorine (40
g/kg·min) is triggered by the gamma motoneurones. Amantadine (50 mg/kg i.v.), which itself elicited tremor activity, abolished the tremor produced by oxotremorine. The tremor activity resulting from an administration of reserpine was inhibited by amantadine in rats with their dorsal roots cut; in rats with intact dorsal roots, tremor activity persisted after reserpine and amantadine.
It is concluded that the tremor resulting from reserpine and oxotremorine is brought about by an action of the two drugs on different structures of the central nervous system. The anti-tremor effect of amantadine is discussed.
Key words Tremor Activity - Alpha and Gamma Motoneurones - Reserpine - Oxotremorine - Amantadine