RESUMO
Liver microsomal concentration of cytochrome P.450 is increased in animals which are fed diets rich in polyunsaturated fatty acids. On the other hand, the effects of phenobarbital are more important when the dietary fat is more unsaturated. The unsaturation index in liver microsomal phosphatidylcholines depends on the unsaturation of the dietary fats. The treatment with phenobarbital constantly results in a decrease of the unsaturation index of fatty acids both in lecithins and cephalins. The importance of the liver microsomal cytochrome P.450 increase and the importance of the unsaturation index decrease in liver microsomal lecithins, both promoted by phenobarbital, are in good agreement.
Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Dieta , Microssomos Hepáticos/metabolismo , Fenobarbital/farmacologia , Fosfolipídeos/metabolismo , Animais , Ácidos Graxos/análise , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Ratos , Ratos EndogâmicosRESUMO
In the series of salicylic acids derivatives investigated 3,5-DIS has a large inductive effect of enzymes with respect to the metabolism of xenobiotics: rise in the rate of Cyt. P 450; increase of ethoxycoumarin deethylase, bilirubin glucuronosyl transferase and benzphetamine-N-demethylase activities. This effect is comparable with that of phenobarbital.
Assuntos
Glucuronosiltransferase , Hexosiltransferases/biossíntese , Iodobenzoatos/farmacologia , Microssomos Hepáticos/enzimologia , Oxirredutases N-Desmetilantes/biossíntese , Oxigenases/biossíntese , Salicilatos , O-Dealquilase 7-Alcoxicumarina , Animais , Fenômenos Químicos , Química , Sistema Enzimático do Citocromo P-450/metabolismo , Indução Enzimática , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Ratos , Ratos EndogâmicosRESUMO
Male Wistar rate were treated with benfluorex, 50 mg/kg/p.p. daily for 7 days. The administration of benfluorex markedly increased the activity of ethoxycoumarin deethylase without increase of cytochrome P 450 levels in hepatic microsomes. The activity of bilirubin glucuronosyl transferase is so much increased with benfluorex than phenobarbital but this effects are not additive. Benfluorex alone affected the fatty acid composition of microsomal lecithins and when given with phenobarbital benfluorex modified the phenobarbital-induced changes in the fatty acid composition of microsomal lecithins. Electrophoresis of microsomal proteins showed non sensitive induction of any proteins with benfluorex.
Assuntos
Indução Enzimática/efeitos dos fármacos , Fenfluramina/análogos & derivados , Microssomos Hepáticos/enzimologia , O-Dealquilase 7-Alcoxicumarina , Animais , Sistema Enzimático do Citocromo P-450/biossíntese , Eletroforese em Gel de Poliacrilamida , Fenfluramina/farmacologia , Glucosiltransferases/biossíntese , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Oxigenases/biossíntese , Fenobarbital/farmacologia , Ratos , Ratos EndogâmicosRESUMO
1. Male Wistar rats were treated with tiadenol, 200 mg/kg/ p.o. daily for 7 days. 2. The administration of tiadenol markedly increased the activity of bilirubin glucuronosyl transferase in hepatic microsomes. Cytochrome P 450 levels and ethoxycoumarin deethylase activity were more slightly increased. 3. Electrophoresis of microsomal proteins showed the induction of a protein with a molecular weight of about 72,000. 4. Tiadenol alone only slightly affected the fatty acid composition of microsomal lecithins and cephalins. When given with phenobarbital, however, tiadenol modified the phenobarbital-induced changes in the fatty acid composition of microsomal lipids.