ABSTRACT
The liver is exposed to many potentially toxic substances and is frequently a target organ in experimental animal studies. The liver is more susceptible to injury because as a portal of entry to the systemic circulation and the other tissues, it is exposed to higher concentrations of foreign substances prior to their dilution in the systemic circulation. The liver also has an extensive role in intermediary metabolism and interference with this by foreign compounds may also make the liver a target organ. Hepatic blood flow is an important factor affecting the metabolic activity of the liver. The extraction of foreign compounds from sinusoidal blood will be influenced by blood flow, which is regulated by the hepatic arterioles. The liver serves three basic functions: it takes up nutrients and exogenous substances from the portal blood, it synthesizes a variety of compounds, and it secretes bile.
