Lecture 17- Chronic Pancreatitis - 15/02/2013
The pancreas is located at the back of the abdominal wall, nuzzled in the C-shaped duodenum. It
has endocrine and exocrine functions.
Endocrinerelease glucagon and insulin.
Exocrine secretes pancreatic juice
The pancreatic duct joins the common bile duct and secretes into the 2nd stage of duodenum,
controlled by the sphincter of Oddi. Anatomically, it's in the epigastric area.
Case Study: Chronic Pancreatitis
Chronicextended time, -itisinflammation
1. How are the endocrine and exocrine functions of the pancreas impaired? Expand on the
cell types present in the pancreas and the composition of pancreatic juice.
Produces an alkaline secretion to neutralize stomach acid. In chronic pancreatitis, the
pancreas is inflamed and the ducts are blocked and some acinar tissue is replaced by
fibrotic tissue after the immune response. Alkaline secretion decreases. Consequences:
o Decrease in enzyme activity (i.e, lipases, proteases, α-amylase). This decrease
impairs absorption because transport mechanisms across the gut are for small
particles (i.e, amino acids).
o Micelles don't form well with low pH and you get steatorrhea (high fat content in
stool) because fat is not broken down or absorbed properly
o Increase in acidity and ulcers. Bicarbonate isn't being released enough to
neutralize the stomach acid.
The overall gland structure is conserved.
o Terminal acinar portion intercalated duct intralobular duct extralobular
ducts (getting bigger and bigger) main collecting duct the pancreatic duct.
The acinus is composed of pyramidal epithelial cells.
Islet of Langerhans is located against the secretory ducts. It is secondarily affected during
chronic pancreatitis because of the inflammation. It's secondary diabetes mellitus.
Ultrafiltrate of the plasma, but has a higher concentration of HCO3- (chyme neutralizer).
Its concentration changes with the rate.
o Proton pump secretes H+ into the blood, which react with HCO3- to make CO2.
CO2 diffuses in the cell and becomes HCO3- again via carbonic anhydrase. o CFTR channels on the surface of duct exchange HCO3- for Cl-. First they secrete
Cl- into the lumen of the duct so Cl- can be present for the exchange.
A mutation in the CFTR gene results in a defective ion secretion and produces a viscous
fluid in the ducts with high protein concentration which can block the lumen and cause
In pancreatitis alkalosis occurs because the pancreas makes alkaline tide.
Why don't you digest yourself from the pancreatic juice?
o The enzymes are not ac