Tacrolymus in experimental head trauma research of histopathological effectiveness

Purpose: In our study, we aimed to investigate the protective effect of Tacrolimus (FK506), an immunosuppressive agent, against secondary brain damage in rats with experimental head trauma. Secondary brain injury was evaluated by the Immun Reactivity Score (IRS) after GFAP staining of gliosin that will occur in the brain tissue. Material and method: In this experiment, 40 Sprague-Dawley rats weighing 250-350 g were used without gender selection. The subjects, divided into 5 groups with 8 rats in each group, were sacrificed 1 month after head trauma under appropriate conditions, their brains were removed en bloc and evaluated histopathologically. Findings: When histopathological IRS values of all groups were evaluated by Kruskal Wallis analysis of variance, it was observed that there were statistical differences between all groups. Later, in the comparison made with Mann Withney - U as paired groups, it was observed that the IRS value increased the most in the Treatment group (p <0.05), but it did not make statistical significance although it increased in Negative Control, Positive Control and Carrier groups. It was found that an advanced histopathological reaction score was the least in the sham group. Conclusion: It was observed that gliosis in the traumatic area increased significantly in the group in which we expected recovery, namely the group given FK506, compared to the other control groups. This situation shows that FK506 cannot prevent or even increase gliosis by an unexplained mechanism. In conclusion, it is clear that FK506 immunosuppressive agent does not reduce post-traumatic damage to the brain contrary to expectations, but rather increases gliosis. Key Words: Head trauma, Tacrolimus, FK506, Gliosis, Secondary Brain Injury