The Effect of Chronic Intermittent Cold Exposure on Gastrin-, Somatostatin-, Secretin-, and Serotonin-Containing Cells in the Small Intestine of Rats

Abstract

Stress is counted among the reasons of many diseases. Exposure to cold is one of the stimulants that leads to stress. No study has been found in the literature showing how the enteroendocrine cells in the small intestine are affected by cold stress. Therefore, this study aimed to investigate the structural changes and the densities of gastrin, somatostatin, secretin and serotonin immunoreactive cells in the small intestines of rats exposed to cold. The rats were randomly divided into two groups as control and cold stress. Exposure to cold was performed as 6 hours once a day for 14 days. At the end of the experiment; duodenum, jejunum and ileum samples were taken from small intestines. For histopathological examination, hemotoxylin-eosin staining method was applied to tissue sections. In addition; gastrin, somatostatin, secretin and serotonin immunoreactive cells were detected in small intestine immunohistochemically. The numbers of gastrin, secretin and serotonin immunoreactive cells in all parts of the small intestine, as well as the number of somatostatin immunoreactive cells in ileum significantly decreased in the cold stress group compared to the control group. Besides, it was found that mucosal inflammation, edema, and villus atrophy increased in the small intestine due to exposure to cold. As a conclusion, cold stress causes structural disorders in the small intestine. Also, it reduces the populations of enteroendocrine cells containing gastrin, somatostatin, secretin and serotonin. Thus, cold stress might play a role in the pathogenesis of some intestinal diseases by adversely affecting digestive physiology.