The accumulation and energy load of exogenous lipids in cirrhotic rat liver after partial hepatectomy.

BACKGROUND

The suitability of three energy substrates, glucose, medium-chain triglycerides (MCT) and long-chain triglycerides (LCT), was studied in cirrhotic rats after a partial hepatectomy.

METHODS

Rats with thioacetamide-induced cirrhosis underwent a 70% hepatectomy, and were divided into three groups. Each group was then injected with 14C-labeled glucose, 14C-labeled MCT or 14C-labeled LCT, respectively. The subsequent tissue distribution of 14C and the cumulative amount of expired 14CO2 were determined. In a second experiment, the 70%-hepatectomized cirrhotic rats received total parenteral nutrition (TPN). The source of the nonprotein calories was 100% glucose (glucose group), 60% MCT + 40% glucose (MCT group), and 60% LCT + 40% glucose (LCT group). The adenylate energy charge and the glycogen content in the liver remnant were determined.

RESULTS

The tissue distribution of 14C revealed that the fat emulsions accumulated preferentially in the liver. One hour after the partial hepatectomy, the concentration of 14C-labeled MCT in the liver remnants was threefold higher than in sham-operated controls. Similarly, the concentration of 14C-labeled LCT was twofold higher. The adenylate energy charge in the glucose group with TPN recovered to preoperative levels within 1-hour after the partial hepatectomy, whereas the LCT group with TPN showed a 24-hour delay in their recovery. The MCT group with TPN exhibited an intermediate time course.

CONCLUSIONS

It is suggested that the specific accumulation of MCT and especially LCT emulsions in the cirrhotic liver remnant acts as an energy load rather than an energy substrate.