Electric injury-induced Purkinje cell apoptosis in rat cerebellum: Histological and immunohistochemical study

- Electric injury is a public problem due to lack of safety knowledge regarding its use.
- Difficulty to decide the cause of death due to electric injury without skin marks.
- Nervous system is susceptible to electrical current because of its low resistance.
- Fatal and non-fatal electric current lead to cerebellar purkinje cell apoptosis.
- Histopathological examination is recommended for final diagnosis of electrocution.

IntroductionElectrical injury is a prominent problem in low income countries with increased morbidity and mortality rate. Nervous system is one of the most susceptible systems to electrical current because of its low resistance. There were different studies demonstrated electrocution effect on the nervous system, however little was made on the cerebellum.AimThis study was conducted to produce an experimental suggestion concerning injury of the nervous system through evaluating Purkinje cell apoptosis and number in rat cerebellum by fatal and non-fatal electric current using histological and immunohistochemical study. Also to support the diagnosis of electrocution as a probable cause of death and delayed neurological damage as well as disability.Materials & methodsFifty male Wistar rats were divided into five groups (10 rats each); control group: normal rats that were sacrificed without exposure to electric current, groups 1-3 (non-fatal electrocution groups): rats were exposed to alternating electric current (220 v, 50 Hz) for one minute then were sacrificed immediately, after 2 h, and after 4 h respectively, and group 4 (fatal electrocution group): rats were sacrificed after being electrified up to death (153 ± 27 s). Sections from cerebellum were processed for histological and caspase-3 immunohistochemical study.ResultsPurkinje cells showed marked histopathological changes in the form of shrunken dark stained cells with significant reduction of their number in H &E stained sections when compared to control, widespread argyrophilia, and degenerated organelles along with shrunken irregular nuclei. For caspase-3 staining, there was significantly increased number of caspase-3 positive cells in groups 1-3 (non-fatal electrocution groups) and markedly increased in group 4 (fatal electrocution group) in comparison to control group. These changes were gradually increased with the increased duration after exposure to the electric current.ConclusionApoptosis and loss of Purkinje cells were involved in the pathogenesis of immediate and long term effect of electrical injury on Purkinje cells, which will be an aid to the forensic pathologist to determine the cause of death and residual damage as well as disability after electric shock.