V. Blaha et al., HYPERCALORIC LIPID AND GLUCOSE-INFUSION REDUCES THE MITOCHONDRIAL RESPIRATORY ACTIVITY IN THE REGENERATING RAT-LIVER, Clinical nutrition, 13(6), 1994, pp. 368-373
In order to evaluate the liver mitochondrial response to an increased
energy load, eight groups of rats were studied: a control group (no su
rgery), a sham-operated group, and 6 groups that had undergone partial
hepatectomy (PH). The PH rats either had no infusion following surger
y, saline, isocaloric lipid, hypercaloric lipid, isocaloric glucose or
hypercaloric glucose infusion. After isolation of liver mitochondria
6, 12, 18 and 24 h after surgery states 3 and 4 of respiration were me
asured in vitro in the presence of succinate. State 3 and 4 mitochondr
ial respiration was higher in the sham-operated rats 6 h after surgery
than in the control animals, and a gradual decrease towards control v
alues occurred in the 12-24 h period following surgery. Results in mit
ochondria from PH rats showed variable results, in most cases both Sta
te 3 and 4 respiration was higher after PH, while the respiratory cont
rol index in general was lower. State 3 respiration was significantly
increased in the PH isocaloric lipid and glucose infused groups 6, 12
and 18 h, but not 24 h after partial hepatectomy. The PH hypercaloric
glucose and hypercaloric lipid infused rats showed decreases in the li
ver mitochondrial oxygen consumption after 6, 12 and 18 h of liver reg
eneration, this was more pronounced after hypercaloric lipid infusion.
These results suggest that, in vitro, the surgery tends to increase S
tatus 3 and Status 4 mitochondrial respiration. The hypercaloric paren
teral nutrition, both lipid and glucose based, significantly decreased
liver mitochondrial oxygen consumption in partially hepatectomized ra
ts, particularly in the first hours of liver regeneration, with restor
ation 24 h after surgery.