title: Ivermectin: concentration-dependent effects on adenosine triphosphatases in adult worms of Onchocerca volvulus.
abstract: The effect of increasing concentrations of ivermectin on adenosine triphosphatase (ATPase) activity was investigated in adult worms of Onchocerca volvulus. Mean Mg- and Na,K-ATPase activities decreased significantly (F ratio = 29.82, P < 0.01 and F ratio = 28.54, P < 0.01, respectively) with increasing concentrations of ivermectin (0-100 ng/ml) in the female worms. When male and female worms were mixed with equal amounts of proteins from each, only the Na,K-ATPase activity was significantly decreased (F ratio = 56.61, P < 0.01) over a similar range of ivermectin concentrations. Since ivermectin exhibits concentration-dependent effects on both ATPases in female adult worms, this might provide an insight into other effects of the drug. However, the adjustment of the dose of ivermectin to obtain a nodular concentration of at least 40 ng/ml is therefore recommended in the complete chemotherapy of onchocerciasis.
authors.affiliation: Department of Pharmacology and Therapeutics, College of Medicine, University of Nigeria, Enugu Campus.
authors.forename: E N
authors.initials: EN
authors.lastname: Shu
authors.forename: P O
authors.initials: PO
authors.lastname: Okonkwo
authors.forename: W O
authors.initials: WO
authors.lastname: Batey
authors.forename: J
authors.initials: J
authors.lastname: Onyeanusi
mesh_terms: D000251:Adenosine Triphosphatases / Q000187:drug effects* / Q000378:metabolism; D000328:Adult; D000704:Analysis of Variance; D000818:Animals; D000981:Antiprotozoal Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007559:Ivermectin / Q000494:pharmacology*; D008297:Male; D009549:Nigeria; D017181:Onchocerca volvulus / Q000187:drug effects* / Q000201:enzymology
chemical_list: D000981:Antiprotozoal Agents; D007559:Ivermectin; D000251:Adenosine Triphosphatases