STRESS AND THE GUT(2)

STRESS AND BRAIN-GUT-MICROBIOTAAXISConcerning the link between stress and gastrointestinaldiseases, most people are aware of the fact that the centralnervous system and the gut are intimately connected. It is wellknown that exposure to stress may lead to the manifestation ofdifferent symptoms within the gastrointestinal tract such asdyspepsia, diarrhoea or abdominal pain. The first observationperformed on the wounded soldier with gastric fistula by WilliamBeaumont showed that fear or anger may significantly influencethe gastric physiology, especially acid secretion (7). In the laterbetween the central nervous system (CNS) and the gut was thediscovery of the enteric nervous system (ENS) in the nineteenthcentury. ENS (called also "little brain") plays a crucial role in theregulation of the physiological gut functions including secretion,motility and release of various neuropeptides and hormones (8).Brain communicates with the gut through multiple parallelpathways including autonomic nervous system (ANS), thehypothalamic pituitary-adrenal axis (HPA), and otherconnections, which were termed the brain-gut-axis (BGA) (Fig.2) (9-10). Based on previous studies there is strong evidence thatexposure to stress may be responsible for the dysregulation of the