Schistosoma mansoni: neurotransmitters and the mobility of cercariae and schistosomules.

The concentration-dependent action of alkyl-isothiouroniums on Schistosoma mansoni cercariae, ranging from partial to total abolition of locomotor and flame cell movements, and/or suppression of virulence, is due to H1-histamine receptor inhibition. Correspondingly, H1-receptor inhibitors of widely different chemical structure, such as clemizol, diphenhydramine, brompheniramine, and promethazine, in 0.03-0.

Trypanostatic drug action: its relation to relapse following chemotherapy.

Analogies with dose-dependent transient prophylaxis and with delayed take of reinfection in drug-cleared Trypanosoma evansi (T. venezuelense) infected animals indicate that relapse following chemotherapy is induced by the same underlying mechanism, i.e.