Related Experiment Video
Updated: Jun 20, 2026
Facial Nerve Axotomy in Mice: A Model to Study Motoneuron Response to Injury
Published on: February 23, 2015
Histopathologic and functional effects of facial nerve following electrical stimulation
Emrah Sapmaz1, Irfan Kaygusuz, Hayrettin Cengiz Alpay
1Department of Otorhinolaryngology, Firat University Medical Faculty, 23200, Elazig, Turkey.
Abstract:
The aim of the study is to investigate the functional and histopathologic changes in facial nerve due to the application of various violent and numerous electrical stimuli to the facial nerve. The study was carried out with Wistar rats weighing between 200 and 300 g. The facial nerves of the subjects were located and stimulated with electrical stimulator. Then five groups were created with 18 subjects in each group: Group 1, 1 milliampere (mA) electrical stimulus applied; Group 2, 2 mA electrical stimulus applied; Group 3, 3 mA electrical stimulus applied; Group 4, 4 mA electrical stimulus applied; Group 5, 5 mA electrical stimulus applied. All groups were divided into three sub-groups, each consisting of six subjects. The facial nerves of the subjects in first sub-group were stimulated 10 times, in second sub-group were stimulated 20 times and those in third sub-group were stimulated 30 times. The functions of the facial nerves were evaluated on first day, first week and first month, respectively. The facial nerves with branches were dissected from the surrounding tissues carefully. These specimens were investigated by light microscope about axonal degeneration, macrovacuolization and vascular congestion. Loss of facial functions was not observed in the subjects during follow-up process. There was no significant difference between groups regarding axonal degeneration, macrovacuolization and vascular congestion (P > 0.05). While less axonal degeneration was observed in group which was stimulated 10 times, more axonal degeneration was observed in groups which were stimulated 20 and 30 times (P < 0.05). The axonal degeneration, macrovacuolization and vascular congestion were observed more in 1-day groups (P < 0.05). Consequently, lesser violence and lesser number of electrical stimulus application to the facial nerve appears to be an important criterion for not damaging the facial nerve in patients in whom stimulators have been used.
