THE EFFECTS OF ADRENALINE, NORADRENALINE, AND ISOPRENALINE ON PARKINSONIAN TREMOR

Abstract

To demonstrate the site of action of catechol amines in aggrevating Parkinsonian tremor the effects of adrenaline, isoprenaline and nor-adrenaline were studied in 25 patients, 15 males and 10 females, 38-56 years of age. Adrenaline and to a lesser degree isoprenaline increased the amplitude of Parkinsonian tremor. No significant change was pro-duced with noradrenaline. The increase in amplitude was less when medication, Artane [trihexyphenidyl], was administered preceding the adrenaline. Following observations made of the effects of using a ganglionic blocking agent, a drug which interferes with the effector organ response, a drug which acts on the postganglionic sympathetic nerve fibres and administering adrenaline intra-arterially and intramuscularly, it was concluded that adrenaline has a central site of action. The most probable location is the reticular formation of the brain stem. It must be a specific area, however, because adrenaline acting on the brain stem appears to inhibit other types of tremor.