1. How signals are delivered
p.291
IV. Integration & Control of G.I. Function
How signals are delivered

2. Regulation of Gastric Activity
p.619 of text
Regulation of Gastric Activity

3. Phases of Gastric Secretion
Cephalic Phase of Gastric Secretion
(initiated by brain)
Gastric Phase of Gastric Secretion
(initiated by gastric events)
vagus nerve
vagus nerve
FOOD
HCl
HCl
Distension
Peptides
circulation
circulation G G
gastrin
gastrin

4. HOW IT WORKS AT THE RECEPTOR LEVEL
Combined neurocrine, endocrine and paracrine events in the activation of gastric HCl secretion
Acetylcholine neural input neurocrine
ACh receptor
PARIETAL cell
histamine receptor
H/K P
ECL cell
transduction-activation events
HCl
secretion
histamine-secreting cell
H/K P
gastrin receptor
paracrine release of histamine
Gastrin hormonal input endocrine
ECL cell =
enterochromaffin-like cell
G cell =
gastrin-secreting cell
circulation
G cell

5. Turning the G-cell On and Off
p.292
Turning the G-cell On and Off
vagus
nerve
ACh
ACh
Circulating
cholinergic neuron
GRP
Gastrin
gastric mucosa
neuron - +
ACh
GRP D G
(Somatostatin)
(Gastrin)
cell SS
cell + + H+
digested
protein
Gastric Lumen
Gastric Lumen

6. Turning the G-cell On and Off
p.292
Turning the G-cell On and Off
vagus
nerve
ACh
ACh
Circulating
cholinergic neuron
GRP
Gastrin
gastric mucosa
neuron
GRP +
ACh D - G
(Somatostatin)
(Gastrin)
cell SS
cell + + H+
digested
protein
Gastric Lumen
SS = somatostatin

7. Integration of Gastric Secretion
p.623 of text
Integration of Gastric Secretion

8. G.I. HORMONES p.293/94 Gastrin (17 AA) Cholecystokinin (CCK (33 AA))
Structure of Secretin (27 AA) (comparison with other GI hormones)

9. Intestinal Phase of Gastric Function D. Duodenal Integration & Control
p.624 of text
Intestinal Phase of Gastric Function
D. Duodenal Integration & Control

10. Duodenal Response to Acidity
Regulation by Secretin + -
gall
bladder
liver
HCl 
motility
NaCl
+ H2O
HCO3
NaHCO3
Secretin
HCl + NaHCO NaCl + CO2 + H2O

11. - Duodenal Response to Food + Regulation by CCK (Cholecystokinin) CCK
gall
bladder 
Bile
FOOD + -
liver
fats & peptides
bile & enzymes
fat & protein digestion
HCl 