The effect of human placental suspension on rat sciatic nerve healing

Objectives: We investigated the effect of human placen¬tal suspension (HPS) on rat sciatic nerve regeneration. Methods: Eight adult female Sprague-Dawley rats weigh¬ing between 250 and 300 g were randomly divided into con¬trol and study groups equal in number. Both sciatic nerves were explored under anesthesia, transsected and then imme¬diately repaired. At the end of the operation, and on the sec¬ond and fifth days, HPS and saline were administered to the operation zone in the test and control groups, respectively. For functional examination, electromyographic activity was measured in posterior extremities of all rats preoperatively and at the end of eight weeks. The rats were then sacrificed to obtain transections from the repaired area and its distal region for histologic examination and the number of myelin-sheathed axons was estimated in both regions. Results: Electromyographic study showed delayed laten¬cy and decreased amplitude following operation in both groups, being less severe in the study group without reaching a significant difference from the control group (p>0.05). The most notable histopathologic finding was increased endoneural collagen in the control group and regenerative axonal growth in the HPS group. The num¬ber of axons was greater in the distal region in both groups. In both regions, the number of myelin-sheathed axons was greater in the HPS group, but this difference was significant only for the number of axons in the repair zone (p=0.001). Conclusion: Our data suggest that HPS may exert a favorable effect on peripheral nerve regeneration.