Noise is considered as one of the most severe sources of environmental and workplace constraints. Many noise effects are well known on immune function, hormonal levels, cardiovascular and respiratory systems. In this study, our aim is to evaluate the effects of traffic noise exposure on basal and stimulated gastric pepsin secretion. 48 male rats were exposed to traffic noise (86 dB) for a short term of (8h/day for 1 day) and a long term of (8h/day for 7, 14, 21 and 28 days) as well as a control group. The gastric contents were collected by the wash-out technique. Pepsin secretion was measured by employing the Anson method. Histological studies were carried out on the epithelial layer. The corticosteroid hormone was measured in the serum for the stress augmentation. The present finding indicated no changes in pepsin secretion content in the short term, but in the 14 and 21 days traffic noise exposure, basal gastric pepsin secretion increased markedly compared to the control group. Histological results showed that the number of oxyntic glands and cell nuclei decreased in comparison with the control group while the thickness of the epithelial layer increases. In addition, the corticosterone levels increase in all groups in comparison with the control. It seems that the increase of gastric pepsin secretion is due to the description and translation processes in the peptic cells and needs enough time for completion.
Keywords: Gastric pepsin; Pentagastrin; Rat; Traffic noise.