Avaliação morfofuncional do implante esplênico autógeno e sua relação com a histologia hepática em um modelo murino de injúria por paracetamol

Abstract

The spleen presents various functions such as phagocytosis of microorganisms, production of immunoglobulins, and blood filtration. The spleen has also an anatomical and functional relationship with the liver, although there are few studies on this topic. The model of splenectomy and autogenous implant of splenic tissue is based on the regenerative capacity of the spleen, being useful to study their functions. The chemical liver injury model consists of the induction of hepatocellular injury for assessment of liver function. The aim of this study was to assess the spleen filtering function of the splenic model, and to evaluate their functional relationship with the liver on the chemical liver injury model. Fifty-two BALB/C mice were randomized into groups: sham operated, total splenectomy, splenectomy and autologous implant of the spleen in the greater omentum, and control. After 7, 14 and 28 days after surgery, splenic filtration was assessed by counting Howell-Jolly corpuscles and erythrocytes with indentations. On day 28, animals received paracetamol at 400mg/kg by gavage and were euthanized after 12 or 24 hours for dosage of liver transaminases and histology of liver and spleen. Regarding the filtering function, the splenectomized group demonstrated insufficient filtration in all analyzes, while the autologous implant group developed progressive recovery of function after the 14th day. Histology of the implants showed, on the 28th day after surgery, morphological similarity to the normal spleen. The assessment of transaminases after drug injury did not allow a definition as to the influence of the spleen on liver function. Liver histology evaluation showed an exacerbation of the injury with time, with more intense centrilobular necrosis in the splenectomized group than in the other, suggesting a protective role of the spleen in liver injury model. Thus, splenic implants showed structural and functional recovery, demonstrating the ability of the autologous implant to revive the filtering function of the intact spleen. Furthermore, the integrity of splenic function may be associated with liver function, since the presence of the spleen or spleen implantation mitigated the effects of chemically induced liver injury.