1. Four groups of rats received a liquid formula diet, given alone (control), or supplemented with either ethanol or phenobarbitone, or both together.
2. The ethanol-treated group showed a fall in plasma triglyceride and a rise in liver triglyceride, as compared with the control rats.
3. The phenobarbitone-treated group showed a marked rise in plasma triglyceride but not in liver triglyceride.
4. The group receiving both ethanol and phenobarbitone also showed a rise in plasma triglyceride, but this was accompanied by a striking increase in liver triglyceride.
5. These results suggest that ethanol and phenobarbitone each stimulate triglyceride synthesis but that in addition ethanol has an inhibitory effect on hepatic triglyceride secretion.