From Science News
Stress disrupts gastrointestinal functions and causes a delay in gastric emptying (how quickly food leaves the stomach). This delay in gastric emptying causes bloating, discomfort and nausea and accelerates colon transit, which causes diarrhea. Oxytocin, an anti-stress hormone, is released from the hypothalamus in the brain which acts to counteract the effects of stress. For a long time, the actions of oxytocin were believed to occur due to its release into the blood with only minor effects on the nerves within the brain that regulate gastrointestinal functions. Activation of oxytocin circuits reversed the delay in gastric emptying that occurs normally in response to stress, by increasing muscle contractions (mobility) of the stomach, while inhibition of these neurocircuits prevented adaptation to stress. In order to identify targets for more effective treatment of disorder gastric responses to stress, it is important to first understand how stress normally affects the functions of the stomach. This research provided new information about the role that oxytocin plays in controlling these nerves and circuits during stress and may identify new targets for drug development.