Page 176 - Color Atlas Of Pathophysiology (S Silbernagl Et Al, Thieme 2000)

B. Cholesterol/Bile Salts: Dependence on Bile Salt Type and Bile Salt Secretion Rate
Cholesterol

12α- 5 [Cholesterol]/[Bile salts]
Estrogens hydroxylase 4

Bile salts Cholesterol secretion [mmol·kg –1 ·h –1 ] 3 2 Cholate
OH COO – 1 Chenodeoxycholate
Liver HO 12 OH COO – HO Chenodeoxycholate 0 0 Bile salt secretion [mmol·kg ·h ] 50
OH
10
20
30
40
Stomach, Intestines, " Cholate ! In acute cholecystitis fever and leukocyto-
–1
–1
(after G. Paumgartner et al.)
The gallbladder, in which the specific bile
many times over by withdrawal of water,
Important causes are trauma to the gallblad-
also plays an important part (→ D) in the for-
der epithelium caused by stones. Prostaglan-
6 components (Ch, BS, Pch) are concentrated sis are added to the symptoms listed above.
mation of gallstones (cholelithiasis after cho- dins are liberated from the gallbladder epi-
lecystectomy is rare). Disorders of gallblad- thelium in addition to phospholipase A 2 . The
der emptying can be among the causes, ei- latter splits phosphatidylcholine to lysoleci-
ther due to insufficient CCK being liberated thin (i.e., removal of the fatty acid at C2),
(lack of free fatty acid [FFA] release in the lu- which in turn brings about acute cholecysti-
men in pancreatic insufficiency), so that the tis. In some circumstances it may lead to
main stimulus for gallbladder contraction is gallbladder perforation.
weakened, or because after nonselective va- ! Bacterial cholangitis usually occurs when
gotomy the second most important contrac- bile flow is stopped because of cholelithiasis.
tion signal, acetylcholine, is absent. Gallblad- A rise in pressure with dilation of the bile
der contraction is also weakened in pregnan- ducts is the result, and posthepatic cholesta-
cy. This means that not only occasional or ab- sis and biliary pancreatitis may also develop.
sent emptying (see above) but also incom- ! In relatively rare cases gallbladder cancer
plete emptying increases the duration for develops on the basis of gallstone disease.
which bile remains in the gallbladder. As a re-
sult, there is enough time for the precipitated
crystals to form large concrements. A raised
mucus secretion (stimulated by prostaglan-
dins) can thus lead to an increased number
of nuclei of crystallization.
Possible consequences of cholelithiasis
are (→ E):
! Colic. When the cystic duct or the com-
mon bile duct is transiently blocked by a
stone, pressure rises in the bile ducts and in-
creased peristaltic contraction in the region
of the blockage causes severe visceral pain
166 in the epigastric area, possibly with radiation
into the back, as well as vomiting (→ p.140).
Silbernagl/Lang, Color Atlas of Pathophysiology © 2000 Thieme
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