Haemonchus contortus: effects of glutamate, ivermectin, and moxidectin on inulin uptake activity in unselected and ivermectin-selected adults.
Using [(3)H]inulin uptake as a measure of pharyngeal pumping activity, we have investigated and compared the effects of glutamate, ivermectin, and moxidectin on inulin uptake in susceptible and ivermectin-selected Haemonchus contortus. Inulin uptake is inhibited by glutamate, ivermectin, and moxidectin, at biologically relevant concentrations. Glutamate influences the responses to both ivermectin and moxidectin, suggesting that these three substances share a common mechanism of action. The effects of ivermectin on inulin uptake, but not moxidectin, are significantly altered as a result of selection with ivermectin. These results suggest that ivermectin and moxidectin may differ, to some extent, in their mode of action responses or mechanisms of resistance.
Paiement
J P
JP
Institute of Parasitology, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, Québec, H9X 3V9, Canada.
Leger
C
C
Ribeiro
P
P
Prichard
R K
RK
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000969:Antinematodal Agents / Q000494:pharmacology*; D005260:Female; D018698:Glutamic Acid / Q000494:pharmacology*; D006189:Haemonchus / Q000187:drug effects* / Q000502:physiology; D007444:Inulin; D007559:Ivermectin / Q000494:pharmacology*; D018942:Macrolides; D008297:Male; D009068:Movement / Q000187:drug effects
D000900:Anti-Bacterial Agents; D000969:Antinematodal Agents; D018942:Macrolides; D018698:Glutamic Acid; D007559:Ivermectin; D007444:Inulin; C027837:moxidectin