Comparison of Two Methods of 2AAF/CCL4 Exposure to Induce Rat Animal Model of Chronic Liver Injury

Since chronic liver injury has becoming a global public health problem, many research to elucidate the pathological and regeneration mechanism, that lead to the need of creating an animal model of chronic liver injury. The aim of the study was to develop and compare two method of 2AAF/CCl4 exposures in male wistar rats and to analyze the subject survival, weight gain, liver anatomy and histopathology. This research was experimental study, conducted in Animal Research Facilities, IMERI Faculty of Medicine Universitas Indonesia, from October 2018-October 2019. We compared two methods of 2AAF/CCl4 exposures to 8 weeks male Wistar rats (n=18), i.e. repetitive 12 weeks (twice a week) subcutaneous CCl4 (2 ml/kg) administration, combined with administration of 2 weeks intragastric 2AAF (10 mg/kg) once a week (group II, n=6 and daily (group III, n=6). The control group (group I, n=6) received equal quantities of subcutaneous olive oil (CCl4 diluent) and intragastric polyethylene glycol (2AAF solvent). Group II showed lowest (p=0.000; one way ANOVA, followed by Tukey’s multiple comparisons test) weight gain (23.4±7.46 g) and highest liver/body weight ratio (4.4±0.20), and loss of liver surface slipperiness. Histopathological examination of treatment group using hematoxylin eosin and Masson’s trichrome stainings showed liver cells damage (fat degeneration, cell swelling, necrosis and inflammation) and fibrosis. Severe pathology was seen in group III than group II, however both have high survival rate (>83%). In conclusion, daily administration of 2 weeks high dose 2AAF (10mg/kg) in combination with 12 weeks repetitive CCl4 (2 ml/kg) could induce severe rat liver cells damage and extensive liver fibrosis with an equivalent safety figure compared to that given once a week.