Hepatocytes were isolated from the liver of adult 90-day-old rats and lipids contents were analyzed as described in "Materials and Methods" and expressed as % of total phospholipids. Hepatocytes were treated with 100 nM NaOH (control) or 10 nM of L-T4 for 30 min. Results are mean ± S.E. of six experiments. * p < 0,05 vs. control.