[Inhibitory effect of bithionol on NADH-fumarate reductase in ascarides].
Yakugaku Zasshi
; 113(9): 663-9, 1993 Sep.
Article
em Ja
| MEDLINE
| ID: mdl-8229665
ABSTRACT
To elucidate the mechanism of anthelmintic action of bithionol, the inhibitory effect of the drug on NADH-fumarate reductase (NADH-FR) of Ascaris lumbricoides suum was examined. NADH-FR, an enzyme of anaerobic carbohydrate metabolic pathway was solubilized from the mitochondria of the worm's muscle with deoxycholate, and then partially purified with the monoethanolamine-Sepharose 4B column chromatography. Rhodoquinone (RQ), which is required for the electron transfer from NADH to fumarate, was separated from the enzyme protein and phospholipids. Although the enzyme protein fraction eluted from the above column did not show NADH-FR activity, this enzyme was reactivated by the addition of purified RQ and phosphatidylcholine. The IC50 value of bithionol for reconstituted NADH-FR was 18 +/- 2 microM. The inhibition type was competitive to RQ. Bithionol inhibited at most 30% NADH-ferricyanide reductase, which did not require RQ, even at high concentration of 150 microM. These results suggest that the pharmacological action of bithionol, a phenolic anthelmintic, depends on the inhibition of the electron transport system by the competition with RQ.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxirredutases
/
Ascaris
/
Bitionol
/
Oxirredutases atuantes sobre Doadores de Grupo CH-CH
Limite:
Animals
Idioma:
Ja
Revista:
Yakugaku Zasshi
Ano de publicação:
1993
Tipo de documento:
Article
País de afiliação:
Japão