Hepatic triglyceride secretion.

Hepatic triglyceride secretion rate was measured as described by Huang et al. (65). Briefly, rats were fasted overnight to remove the chylomicrons from the plasma. After obtaining the baseline samples, the rats received a bolus injection of tyloxapol (triton WR1339, Sigma-Aldrich; 300 mg/kg, i.v.) in the tail vein. Blood samples were collected at 0, 60, 90, 120, and 150 minutes after tyloxapol injection, and triglyceride content was measured in the plasma. Triglyceride secretion rates for each rat were calculated by simple linear regression plasma triglyceride levels (mg/kg body weight) as the dependent variable and time of measurement (hours) as the independent variable.