Vitro Tests for Gene Mutation in Bacteria

It should be noted that this system is only a first approximation to the complex metabolic processes that occur in vivo, and in particular there is little account taken of the phase 11 detoxification reactions. Such factors should be considered when interpreting positive in vitro results that are only seen in the presence of S9 mix. It should be noted that some cytochrome P450s in induced S9 are so greatly elevated above the levels in normal liver (see Table 11.1) that reactive metabolites may be produced in significant quantities in vitro that would be negligible in normal livers in vivo. 

The most widely used assays for detecting chemically induced gene mutations are 

TABLE 11.1. The Impact of Aroclor on the Induction of Various CYPs in Comparison to Normal Rat and Human Liver  

Enzyme Untreated Rat Aroclor-Treated Rat Induction Factor (Rat) Level in Human Liver 

In most regnlatory test gnidelines, the following base set of bacterial test strains is recommended  

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