Effect of total parenteral nutrition on liver mitochondrial function in mature rats

To evaluate the effects of TPN on the hepatic function, the changes in hepatic energy charge levels, oxidative and phosphorylative activities of mitochondria and serum transaminase were studied, using male Sprague-Dawley rats 240 to 250 g in weight. The rats were randomized into three groups. The first group (TPN-V group, n = 6) was infused with TPN solution via the right jugular vein. The number of calories of TPN solution infused daily was adjusted to provide each rat with 80 kcal/kg/day on the 1st day, 160 kcal/kg/day on the 2nd day and 240 kcal/kg/day on the 3rd day. After the 4th day, 240 kcal/kg/day was given to both groups. The second group (TPN-G group, n = 5) was infused with the same solution via an intragastric route and was given the same calories as the TPN-V group. The third group (control group, n = 6) was given a chow diet with the same calories as the TPN group. At the 13th day, all groups were sacrificed, and the hepatic energy charge (EC) and phosphorylation rate (PR) of hepatic mitochondria were measured, and liver function tests were done. PR was 101.2 +/- 5.0 nmol/mg protein/min in control group, 120.8 +/- 2.7 in TNP-G group and 136.5 +/- 6.2 in TPN-V group. EC was 0.906 +/- 0.006, 0.889 +/- 0.008, 0.831 +/- 0.010, respectively. The liver function tests of all group were normal. In both TPN groups, despite evidence that liver function tests were normal, enhanced mitochondrial phosphorylative activity was observed during the early stage of TPN.(ABSTRACT TRUNCATED AT 250 WORDS)