In vitro metabolism of moxidectin in Haemonchus contortus adult stages.
We studied the implication of cytochrome P450 enzymes in the in vitro metabolism of moxidectin (MXD) in homogenates of Haemonchus contortus adult stages (susceptible isolate, Weybridge, UK). After homogenisation in a phosphate buffer, 2 ml of homogenates (equivalent to 1 g of nematodes) were incubated with 5 microg [14C] MXD at 37 degrees C for 24 h. MXD and its metabolites were separated by HPLC with radiodetection on-line. Only one metabolite was detected and its production was inhibited by carbon monoxide. This result demonstrates that the cytochrome P450 system is implicated in the metabolisation of MXD in H. contortus susceptible to milbemycin. Furthermore, this metabolite did not match those previously described in vertebrates.
Alvinerie
M
M
INRA, Laboratoire de Pharmacologie-Toxicologie, Toulouse, France. malviner@toulouse.inra.fr
Dupuy
J
J
Eeckhoutte
C
C
Sutra
J F
JF
Kerboeuf
D
D
D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology; D000969:Antinematodal Agents / Q000378:metabolism* / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005260:Female; D006188:Haemonchiasis / Q000469:parasitology; D006189:Haemonchus / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D018942:Macrolides; D008297:Male
D000900:Anti-Bacterial Agents; D000969:Antinematodal Agents; D018942:Macrolides; D003577:Cytochrome P-450 Enzyme System; C027837:moxidectin