Histopathological Effects of Chronic White Noise Exposure on the Brain, Heart, Testis and Intestine of Wistar Albino Rats: Restorative Potential of Post-exposure Ascorbic Acid

Noise is a common environmental stressor that may induce structural alterations in multiple tissues following chronic exposure. This study aimed to evaluate the histopathological changes induced by chronic exposure to 70 dB SPL broadband white noise in the brain, heart, testis and intestine of Wistar albino rats and to investigate the potential restorative effects of post-exposure ascorbic acid administration.

Twenty W istar albino rats aged 8-10 weeks were randomly assigned to control or noise-stress groups. Rats in the noise-stress group were exposed to 70 dB SPL broadband white noise for 1 h/day for 30 days. After exposure, five animals from each group were euthanized and brain, heart, testis and intestinal tissues were collected for histopathological examination. The remaining animals received ascorbic acid in drinking water at 100 mg/kg/day for 30 days, after which the same tissues were examined histopathologically.

Chronic exposure to white noise resulted in histopathological alterations of varying severity in all examined organs. Intestinal tissues showed epithelial degeneration, desquamation and inflammatory cell infiltration in the lamina propria. Brain sections demonstrated gliosis and neuronal degeneration. Testicular tissues showed degeneration and necrosis in some seminiferous tubules, while hyaline degeneration was observed in the myocardium. Following ascorbic acid administration, lesion severity was reduced compared with the noise-stress group and overall tissue architecture was better preserved.