Effects of chronic immobilization stress on the histomorphology of rabbit liver

ABSTRACT

The current study was planned to evaluate the changes produced in liver histology by giving chronic immobilization stress to the animals for 4 weeks. Study was carried out in Army Medical College, Rawalpindi from Jan 2011 toAug2011. Ten adult New Zealand White rabbits were randomly divided into two groups. Group I served as control while group II was an experimental group whose left leg was immobilized in extension for 4 weeks. Following euthanasia, liver was exposed; dissected and was examined for gross and microscopic appearance. Liver from the experimental groups exhibited mild to moderate architectural distortion. Majority of the cases [80%] revealed moderate steatosis predominantly [80%] microvesicular in type. Steatosis was present in all the three zones of hepatic lobule in 4 out of 5 cases whereas one case demonstrated fat vacuoles around the periportal area. When assessed according to modified Knodell's scoring system, mild inflammation was found in 60% of cases while 40% revealed moderate inflammation. All the cases showed focal necrosis along with pyknotic nuclei while karyorrhexis were present in 3 out of 5 cases. Sinusoidal congestion [80% of cases] and dilatation [40% of cases] was also noted in experimental group. Data analyses indicate that liver experiences stress induced injury following chronic immobilization like other organs. Further research is required to evaluate the effects of remobilization on the liver and whether remobilization could cause reversal of these changes. This study could help to take decision to plan the immobilization time during various surgical procedures in orthopedic practice. This would help to save the functions of vital organs like liver