The effects of total parenteral nutrition associated to bacterial infection on the hepatobiliary function of Wistar rats

Abstract

OBJECTIVE: To evaluate the hepatic alterations associated to parenteral nutrition in
rats.
MATERIAL AND METHODS: Four groups with 10 rats each: Group I (control group) -
rats were orally fed with a regular diet; Group II - rats received a regular diet, and were
infected with Escherichia coli through intraperitoneal inoculation; Group III - rats received
parenteral nutrition; and group IV, rats received parenteral nutrition, and were infected
with Escherichia coli. Serum concentrations of AST, ALT, GGT, and 5’ N were measured
on the first day of the experiment, and on the eighth day of parenteral nutrition (the day
animals were sacrificed). Histological study of the liver of the rats included: evaluation
of hydropic degeneration, dilation of the central lobular vein, cholestasis, sinusoidal
dilation, proliferation of Kupffer cells, cellular necrosis, and steatosis. All alterations
were graded from 0 to 4+.
RESULTS: The lab exams did not present consistent alterations at the end of the
experiment. Group IV presented a reduction in GGT concentration; in addition, this
group presented the largest variations in AST and ALT concentration, possibly as a
result of being submitted to more intense aggression to the hepatic parenchyma. From
a histological point-of-view, all animals (with the exception of one) presented dilation of
the central lobular vein and of the sinusoids. Such findings were more frequent among
infected animals. The animals did not present steatosis or cholestasis.
CONCLUSIONS: 1) The proposed model of intraperitoneal inoculation of Escherichia
coli was appropriate for the study of bacterial infection in young rats of the Wistar
strain; 2) our results indicate that the association of parenteral nutrition and infection
determined histologic alterations which were unspecific, but more intense than the
alterations determined by each of these situations in isolation.