fumarates and 2-5-dichloro-4-bromophenol

1. Phebrol (sodium 2,5-dichloro-4-bromophenol), a synthetic molluscicide against Oncomelania nosophora, showed a dual effect on rat liver submitochondria, acting as an uncoupler at low concentrations (approximately 10 microM) and an inhibitor of succinate-cytochrome c reductase at high concentrations. 2. Phebrol also inhibited the enzymes responsible for succinate-fumarate conversion, i.e. the succinate-cytochrome c reductase, fumarate reductase and NADH-cytochrome c reductase of the mitochondrial fraction from Biomphalaria glabrata. 3. Kinetic inhibition studies showed succinate-cytochrome c reductase of B. glabrata and O. nosophora to be more sensitive than that of rat liver toward phebrol. 4. Phebrol accumulated in whole tissues of B. glabrata and O. nosophora and had significant effects on the production of succinate, fumarate and malate by these snails. 5. On the basis of these results, the possible sites of inhibition by phebrol of snail respiratory chains are proposed.

Topics: Animals; Biomphalaria; Chlorophenols; Fumarates; Kinetics; Liver; Malates; Mitochondria; Molluscacides; NADH Dehydrogenase; Oxygen Consumption; Rats; Snails; Succinate Cytochrome c Oxidoreductase; Succinate Dehydrogenase; Succinates; Succinic Acid; Uncoupling Agents