The Effects of Chronic Social Defeat Stress on Solid Gastric Emptying and Defecation in C57BL/6J Mice

Stress contributes to mental disorders as well as functional gastrointestinal disorders. In functional gastrointestinal disorders, gastrointestinal motility is thought to play a role. Therefore, we evaluated the effects of chronic social defeat stress on gastrointestinal motility in C57BL/6J mice, by measuring gastric emptying, fecal pellet output, and gastrointestinal transit. In mice subjected to 10 days of social defeat stress, serum corticosterone concentrations were significantly higher, relative tissue weights of spleen and adrenal gland tissues were significantly heavier, and thymus sizes were smaller than in the control mice. Stressed mice exhibited social avoidance behavior in a social interaction test and anxiety-like behavior and lower locomotor activity in an elevated plus maze test. In gastric emptying test, stressed mice displayed increased gastric emptying rate with significant suppression of short-time (30 min.) test diet intake. Fecal pellet output and gastrointestinal transit were not different in control and stressed mice. These results suggest that chronic social defeat stress influences gastric motility. Thus, the social defeat stress model may be useful for studying psychiatric disease and functional gastrointestinal disorders simultaneously.