[Identification of the catecholamines in tissue extracts of the trematode, Fasciola hepatica].

Dopamine was identified in extracts from Fasciola hepatica by the fluorometric method. It was found that the dopamine concentration in F. hepatica was 0.668 +/- 0.027 micrograms/g of wet weight. The head region (including the oral and ventral suckers) contained 1.658 +/- 0.275 micrograms/g of dopamine (0.016 +/- 0.002 micrograms per parasite), while the posterior region (located behind the ventral sucker) contained 0.278 +/- 0.070 micrograms/g of dopamine (0.014 +/- 0.004 micrograms per parasite). When the worms were treated with DL-DOPA, the concentration of dopamine increased. In helminths treated with reserpine a marked decline of dopamine level was observed. Adrenaline and noradrenaline were not detectable in F. hepatica.