In vivo effects of the kavapyrones (+)-dihydromethysticin and (±)-kavain on dopamine, 3,4-dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid levels in striatal and cortical brain regions

The in vivo effect of a single oral dose of 100 mg (+)-dihydromethysticin/kg body weight on striatal and cortical tissue concentrations of dopamine, serotonin, 3,4-dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid, as well as the dopamine and serotonin turnover, was tested in rats. Additionally, other rats were fed with a (+/-)-kavain containing food over a period of 78 days in order to calculate the influence of a chronic treatment with kavapyrones on the neurotransmitters. The results of the present in vivo study clearly demonstrate that neither (+)-dihydromethysticin in a high single dose, nor (+/-)-kavain chronically administered, altered the dopaminergic or serotonergic tissue levels in rats significantly.