Stereologic and ultrastructural comparison of human and rat amniotic membrane wrapping for rat sciatic nerve repair.

In this study we aimed to examine the effects on wound healing and nerve regeneration of human and rat amniotic membrane wraps around primary epineural anastomosis areas after a peripheral nerve transection injury in rats. We randomized 25 male adult rats with induced peripheral transection injuries into 5 groups (control, transection injury, primary epineural anastomosis [PEA] after injury, PEA with a human amniotic membrane [hAM] wrap, and PEA with a rat amniotic membrane [rAM] wrap groups and treated their injuries accordingly. We took tissue samples from the anastomosis regions, 12 weeks after the experiment, and analyzed them stereologically and ultrastructurally. We performed a statistical analysis with the recovered stereological counts and the measurement data. Our results showed that the use of amniotic membranes for allografts (between same species) instead of xenografts (between different species), along with microsurgery, provides a suitable microenvironment during the healing process with less immunological reaction on the injured site and supports axonal regeneration.