title: The binding of hexobarbital and aniline to cytochrome P-450 of liver microsomes from control and phenobarbital-treated rats of different ages.
abstract: The spectral changes due to the binding of hexobarbital and aniline to cytochrome P-450 of rat liver microsomes were investigated in 10-day- to 15-month-old rats. The Ks values for both substances and consequently the affinity for cytochrome P-450 do not change during ageing. Phenobarbital treatment does not alter the affinity of hexobarbital, but enhances the Ks value for aniline. The maximal spectral changes (delta A max) due to aniline are nearly equal in all age groups whereas delta A max due to hexobarbital is very small in young rats and increases considerably during ageing. The age-dependence of the hexobarbital-induced delta A max is similar to the development of drug-metabolizing reactions. delta A max due to hexobarbital and aniline is enhanced by phenobarbital treatment of the rats. The addition of aniline to microsomes enhances the Ks value and diminishes delta A max for hexobarbital.
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D006591:Hexobarbital / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D010634:Phenobarbital / Q000494:pharmacology*; D051381:Rats
chemical_list: D000814:Aniline Compounds; D003577:Cytochrome P-450 Enzyme System; D006591:Hexobarbital; D010634:Phenobarbital