ACUTE INHIBITION OF LIPID TRANSPORT IN RAT INTESTINAL LYMPH BY ETHANOL ADMINISTRATION

Abstract

To observe the effect of acute ethanol ingestion on stable lipid transport in intestinal lymph, three groups of mesenteric lymph fistula rats were prepared. In group A rats, lipid emulsion containing 120 mumol/hr of oleate (control meal) was infused intraduodenally for 8 hr. Group B rats were infused with another lipid emulsion, which had the same basic composition as the control meal but included 0.75 g/kg body weight/hr of ethanol (alcohol meal), for 8 hr. In group C, rats were infused with the control meal for the first 4 hr, then with the alcohol meal for the next 4 hr. Lymph flow increased just after the infusion of ethanol, that is, lymph flow in group B was significantly higher than that of group A at 1 and 2 hr, and lymph flow in group C was significantly higher than that of group A at 5 hr. In group A, lymphatic triglyceride (TG) output reached a plateau of more than 30 mumol/hr after 3-hr infusion. TG output in group B was significantly lower than that in group A from 2 hr to 8 hr and was two-thirds that of group A at the plateau level. In group C, TG output was the same as in group A until 5 hr, but decreased to two-thirds of that in group A at 6 hr, 2 hr after replacing the control meal with the alcohol meal. Lymphatic phospholipid output exhibited a tendency similar to that of TG output. Comparisons of group A vs. B and A vs. C clearly demonstrated an inhibitory effect of ethanol on stable lipid transport in intestinal lymph. A 2-hr infusion was enough for ethanol to exhibit its inhibitory effect. In conclusion, stable lymphatic transport of intestinal absorbed lipid was suppressed by acute ethanol ingestion.