LIVER MICROSOMAL FATTY-ACID COMPOSITION IN ETHANOL-FED RATS - EFFECT OF DIFFERENT DIETARY FATS AND RELATIONSHIP TO LIVER-INJURY

The rat intragastric feeding model for alcoholic liver disease was use d to study the effect of different diets on the fatty acid compo sitio n of liver microsomes. Rats were fed corn oil and ethanol (CE), satura ted fat and ethanol (SF+E) or corn oil and dextrose (CD) for either 2 or 4 weeks. Rats were also fed saturated and dextrose (SF+D) for 4 wee ks. In comparison with the CD diet, lower levels of arachidonic acid w ere detected in rats fed the CE, SF+E, and SF+D diets. However, the di et-induced changes in levels of arachidonic acid varied as a function of length of feeding. In rats fed the CE diet, we detected a significa nt decrease in the level of arachidonic acid compared with CD animals. Conversely, in rats fed the SF+E diet, the level of arachidonic acid increased compared with the SF+D group. In addition, a significant cor relation was noted between levels of oleic acid and arachidonic acid i n both corn oil (r = -0.85, p < 0.01) and saturated fat (r = -0.76, p < 0.05) groups. However, the changes in levels of arachidonic acid and oleic acid were in opposite directions in the two groups. Levels of d ocosahexaenoic acid decreased between the 2 and 4 weeks in animals mai ntained on the CE diet. Levels of stearic acid increased between 2 and 4 weeks in rats fed the SF+E diet. The lowest level of linoleic acid was detected in the SF+D and SF+E groups, but levels of linoleic acid remained constant in all groups throughout the study. Histological eva luation indicated that ethanol-induced liver injury was limited to rat s fed the diet containing corn oil for 4 weeks. Thus, diet-dependent d ifferences in liver microsomal fatty acid composition may help to expl ain why ethanol induced liver injury occurs in rats fed corn oil, but not saturated fat.