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398 seCtion iii Gastrointestinal ` gastrointestinal—PHarmaCology Gastrointestinal ` gastrointestinal—PHarmaCology

Pancreatic Very aggressive tumor arising from pancreatic ducts (disorganized glandular structure with cellular
adenocarcinoma infiltration A ); often metastatic at presentation, with average survival ~ 1 year after diagnosis.
Tumors more common in pancreatic head B (lead to obstructive jaundice). Associated with CA
A
19-9 tumor marker (also CEA, less specific).
Risk factors:
ƒ Tobacco use
ƒ Chronic pancreatitis (especially > 20 years)
ƒ Diabetes
ƒ Age > 50 years
ƒ Jewish and African-American males
B Often presents with:
ƒ Abdominal pain radiating to back
ƒ Weight loss (due to malabsorption and anorexia)
ƒ Migratory thrombophlebitis—redness and tenderness on palpation of extremities (Trousseau
syndrome)
ƒ Obstructive jaundice with palpable, nontender gallbladder (Courvoisier sign)
Treatment: Whipple procedure (pancreaticoduodenectomy), chemotherapy, radiation therapy.

` gastrointestinal—PHarmaCology

Acid suppression therapy

GRP

Vagus nerve
G cells ECL cells

Ach Gastrin Histamine Somatostatin Prostaglandins

H blockers
2
Atropine
CCK H receptor
B
M receptor receptor 2
3
CI – G q G s G i
– –
HCO 3 HCO +H + cAMP
3
”alkaline tide”— ↑ blood pH IP /Ca 2+
3
after gastric acid secretion
(eg, after meals, vomiting) H CO 3 CI – Gastric
2
Carbonic anhydrase parietal
cell
CO + H O
2 2
ATPase
Proton pump inhibitors Lumen
Misoprostol
Antacids H + K + Sucralfate,
bismuth

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