HEPATIC RESPONSE TO A VERY-LOW-ENERGY DIET AND REFEEDING IN RATS

Hepatic effects of very-low-energy diets (VLEDs) and refeeding were st udied in dietary obese rats. Rats weighing 490-530 g (ages 72-119 d) w ere randomly assigned to control (C) and VLED groups. Control animals consumed a complete diet ad libitum whereas VLED animals consumed 20% of the energy intake of C animals for 7, 14, or 21 d, and some VLED an imals were refed the C diet for 7 d. Hepatic weights, lipid, DNA, and total protein decreased in VLED animals. Observed hepatocytic lipid wa s high in C and progressively decreased in VLED rats. Hepatocytes from VLED rats lost cytoplasmic organelles, contained myelin figures, and became smaller. Decreased protein-DNA ratios and lipids in these same animals is consistent with atrophy. Other biochemical findings include d reductions in blood urea nitrogen, albumin, triglycerides, total pro tein, and glucose, all of which are synthesized or metabolized by the liver. These observations suggest that attenuation of hepatic function is likely.