Effect of FK506 on functional recovery of peripheral nerve after end-to-side anastomosis / 中国组织工程研究

ABSTRACT

BACKGROUND: Injured nerve can regenerate through end-to-side anastomosis and obtain partial physiological function in animal experiment. As an immuno-suppressivedrug, FK506, which is characterized by promoting neural growth and functional recovery, is paid widely attention to.OBJECTIVE: To investigate the effect of FK506 on functional recovery of peripheral nerve after end-to-side anastomosis.DESIGN: Randomized controlled animal study.SETTING: Department of Operation Surgery, Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology.MATERIALS The experiment was completed in the Department of Operation Surgery, Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology in March 2005. Totally 26female Wistar rats were selected and divided into experimental group and control group with 13 in each group.METHODS: Peroneal nerve was transacted on the right side of all the animals, the proximal end of peronieal nerve was turned back and ligated, and the distal end was sutured to the side of tibial nerve with perineurial window. No operation was done on the left side. FK506 was injected in the right tibial muscle (2 mg/kg· d), once a day within two weeks in the experimental group, and saline was used in another group as contrast.MAIN OUTCOME MEASURES: Three months afteroperation, the bilateral common peroneal nerve and the tibial muscle were taken for electrophysiological and histological examination, and the number of common peroneal nerve fiber, area of tibialis anterior muscle fiber of transverse section and muscle wet weight of tibialis anterior muscle were measured. The results were expressed with the ratio between right side and left side (i.e.recovery rate).RESULTS: Totally 26 rats entered the final analysis. ① Results of histological examination Both ratio of number of nerve fiber and ratio of area of muscle fiber in the experimental group were higher than those in the control group (0.734±0.143, 0.412±0.119; 0.628±0.125, 0.432±0.135; P ＜ 0.01,0.05). ② Results of electrophysiological examination Recovery rate of action potential, recovery rate of single muscular contractility and recovery rate of tetanus contractility in the experimental group were higher that those in the control group (P ＜ 0.05). ③ Ratio of wet weight in the experimental group was higher than that in the control group (0.765±0.101,0.513±0.116, P ＜ 0.05).CONCLUSION: FK506 injected into targeted muscle can promote growth and functional recovery of peripheral nerve in end-to-side anastomosis.