title: Drug metabolism components in liver microsomes from Hypostomus punctatus, a Brazilian benthic fish (Cascudo).
abstract: 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.
authors.affiliation: Departamento de Bioquïmica e de Biologia Celular, Universidade do Estado do Rio de Janeiro, Brazil.
authors.forename: J C
authors.initials: JC
authors.lastname: Bastos
authors.forename: V L
authors.initials: VL
authors.lastname: Bastos
authors.forename: P
authors.initials: P
authors.lastname: Burth
authors.forename: R
authors.initials: R
authors.lastname: Harab
authors.forename: M G
authors.initials: MG
authors.lastname: de Luna
authors.forename: A
authors.initials: A
authors.lastname: Rossini
authors.forename: M V
authors.initials: MV
authors.lastname: Faria
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D001938:Brazil; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D005260:Female; D005399:Fishes / Q000378:metabolism*; D006454:Hemoglobins / Q000302:isolation & purification; D008658:Inactivation, Metabolic / Q000502:physiology; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D010619:Phenazines / Q000494:pharmacology; D051381:Rats; D014873:Water Pollutants / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D006454:Hemoglobins; D010619:Phenazines; D014873:Water Pollutants; D014874:Water Pollutants, Chemical; C028122:5-ethylphenazine; D003577:Cytochrome P-450 Enzyme System; D009251:NADPH-Ferrihemoprotein Reductase; D001205:Ascorbic Acid