6. How to detect hepatotoxicity in toxicology studies?

Regulatory toxicology studies must include clinical biochemistry analyses to detect impairment of liver function. These analyses are carried out at the end of the study, when the animals are euthanized for short 28-day studies. Intermediate blood samples are taken during the study for toxicology studies lasting longer than 28 days, in order to observe the time of onset and evolution of liver damage during the course of the study.

The investigations cover the following parameters:

• at least two enzymes indicative of hepatocellular effects (alanine aminotransferase, aspartate aminotransferase, glutamate dehydrogenase);

• total bile acids ;

• at least two enzymes indicative of hepatobiliary effects (alkaline phosphatase, gamma-glutamyl transferase, 5'-nucleotidase,...