Sindirim Sistemi

1
p.291
IV. Integration Control of G.I. Function
How signals are delivered
2
p.619 of text
Regulation of Gastric Activity
3
p.292
Phases of Gastric Secretion
Gastric Phase of Gastric Secretion (initiated by
gastric events)
Cephalic Phase of Gastric Secretion (initiated
by brain)
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
HCl secretion
transduction-activation events
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
p.292
Turning the G-cell On and Off
vagus
nerve
ACh
ACh
Circulating
GRP
Gastrin
cholinergic neuron
gastric mucosa
neuron

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

GRP
ACh
G
D
(Gastrin)
(Somatostatin)
cell
cell
SS
digested
protein
Gastric Lumen
SS somatostatin
7
p.623 of text
Integration of Gastric Secretion
8
p.293/94
G.I. HORMONES
Gastrin (17 AA)
Cholecystokinin (CCK (33 AA))
Structure of Secretin (27 AA) (comparison with
other GI hormones)
9
p.624 of text
Intestinal Phase of Gastric Function
D. Duodenal Integration Control
10
Duodenal Response to Acidity
p.294
Regulation by Secretin
HCl NaHCO3 NaCl CO2 H2O
11
Duodenal Response to Food
p.294
Regulation by CCK (Cholecystokinin)