Transcript GutStress2001

Psychological Stress and your
Gastro-intestinal system
Stress and Digestion
• DIGESTION
- Secretion of saliva
- Stomach
- muscles contract
- secretion of hydrochloric acid (HCl)and enzymes
- mucus membrane protects stomach
- Small intestine
1. Peristalsis (directional contraction)
2. Addition of water
- Large intestine
- water re-absorption into blood
Key point
Huge amounts of energy are required
Along Comes Psychological
Stress
• Digestive process stops
Conserve energy
- no saliva
dry mouth
- no stomach contractions
- no HCl or enzyme secretion
- no peristalsis
- no water re-absorption
• Blood flow to stomach decreases
- patient named Tom – 1940s
• Sympathetic nervous system activation
Ulcer – A hole in the wall of an
organ
• Historically, stress believed to induce GI ulcers
• 1983 – the Helicobactor pylori bacteria discovered
- infects cells of the stomach lining
- infected cells no longer immune to HCl
- HCl
destroys cells
hole in stomach wall
• Result: A shift away from stress contribution to
ulcers
• But: 15 % of people with ulcers aren’t infected
with Helicobactor pylori
But: Only 10% of those infected with Helicobactor
pylori get ulcers
Another factor must be involved
Stress
Modern Theory:
There is a role for stress and
bacteria in ulcer formation
Stress-induced Ulcer
Formation
• Acid Rebound
- Digestion HCl secreted
- Along comes chronic stress
1. Digestion is inhibited
2. No HCl secretion leading to:
- undersecretion of mucus coating
Ulcer Mechanism-cont.
• End of stress period
1. Eat that piece of chocolate cake
HCl secreted
2. Stomach defenses for HCl are down (less mucus
secreted)
3. HCl damages stomach wall
RESULT:
Ulcers formed during recovery from stress
Ulcer Mechanism-cont.
• Stress-induced decrease in stomach blood flow
- lack of oxygen
kill cells
ulcers
- Less blood to flush away HCl
- HCl can attack cells of stomach wall
ulcers
Stress
Bowels in an
Uproar!!
sympathetic nervous system activation
stimulates muscular contractions in large intestine
moves feces along faster - Why?
move feces along faster
no time for water re-absorption
Diarrhea!!