In conclusion, our preliminary result demonstrated that fenofibrate treatment and especially the overdose of rats with chronic hypertriglyceridemia and mild hepatic steatosis decreased mRNA of Abcb1a/Mdr1a and Abcb1b/Mdr1b genes as well as the protein content of ABCB1. The gene discussed is ABCB1; the disease is hypertriglyceridemia.