Biogenic Amines in Experimental and Clinical Myotonya

Abstract

Experimental results obtained on patients with Parkinsonism have shown that Dopamine (D) has only a slight effort on tremor and that this substance removes successfully muscular rigidity in these patients. For these reasons the present authors wanted to find out whether Dopamine might cure rigor provoked by 2,4 dichloiphenoxyacetic acid (2,4 D). It is well known that 2,4 D provokes symptoms very similar to congenital, myotony. Therefore, the authors performed experiments with rats. The animals were given 400 mg of 2,4 D intraperitoneally. The results have shown that an intravenous injection of Doipamme (50—100mg/kg) removed the myotony of masseters in rats, or prevented the occurrence of it, providing D had been administered before 2,4 D. It should be pointed out that the authors also showed that 5-hydroxytryptophane, which is the precursor of serotonin, had the same effect on experimental myotony as Dopamine.

The experiments carried out so far on patients with congenial myotony have shown that the doses given failed to improve the clinical picture. The question arises whether this negative effect in man is due to the rather small doses of L-dopa.