ascorbic-acid and 5-ethylphenazine

1. The major components of hepatic drug biotransformation system were identified in a Brazilian freshwater benthic fish. 2. Cytochrome P-450 difference spectra were obtained adding 0.02 mM phenazine ethosulphate and 2 mM ascorbate to microsomal suspensions. Basal levels of P-450 were high (0.9 nmol/mg of microsomal protein) and were not induced by 3-MC. 3. Microsomal NADPH-cytochrome C reductase activity was determined in presence of 1.3 x 10(-4) M NADPH, 3.3 x 10(-5) M cytochrome C, 1.0 x 10(-4) M EDTA, 66 micrograms of microsomal protein per ml in a 0.3 M Tris-HCl buffer, pH 8.6. Basal levels of NADPH-cytochrome C were 152.7 nmoles/min/mg of microsomal protein.

Topics: Animals; Ascorbic Acid; Brazil; Cytochrome P-450 Enzyme System; Female; Fishes; Hemoglobins; Inactivation, Metabolic; Male; Microsomes, Liver; NADPH-Ferrihemoprotein Reductase; Phenazines; Rats; Water Pollutants; Water Pollutants, Chemical