IMPORTANCE OF T-CELL-DEPENDENT INFLAMMATORY REACTIONS IN THE DECLINE OF MICROSOMAL CYTOCHROME-P450 CONCENTRATION IN THE LIVERS OF RATS INFECTED WITH FASCIOLA-HEPATICA

The concentration of cytochrome P450, measured spectrophotometrically in microsomal preparations from the livers of rats infected with 30 me tacercariae of Fasciola hepatica, declined by approximately 50% at 3 w eeks postinfection. Treatment of infected rats with the anti-inflammat ory agent dexamethasone (2 mg/kg at 48 h intervals for 8 days prior to assay) abolished the decline in P450 content. Assay of P450 in infect ed congenitally athymic (nude) rats showed normal levels. These result s demonstrate that the T-cell-dependent inflammatory response in the l iver of the host is a necessary factor in the development of the decli ne in hepatic P450, which is known to compromise the metabolism of cer tain drugs in infected hosts.