Mr. Smart Guy says…
Your fascination with fecal matter is disturbing. Perhaps I could offer you insight as to why it is brown.
Urobilinogens are colorless compounds formed by bacteria in the intestine from bilirubin after the conjugated glucuronic acid has been removed.
A small portion of the urobilinogen is reabsorbed, extracted from the circulation by the hepatocytes and excreted by the kidney. This constitutes the normal "intrahepatic urobilinogen cycle".
If excessive amounts of bilirubin are formed, as in hemolysis, and/or a liver disease such as hepatitis interferes with the intrahepatic urobilinogen cycle, increased amounts of urobilinogen may appear in the urine where it is converted to yellow urobilin.
The urobilinogen remaining in the intestine is oxidized to brown stercobilin which gives the feces their characteristic color.
In biliary obstruction, subnormal amounts of conjugated bilirubin reach the intestine for conversion to urobilinogen. With little urobilinogen available for reabsorption and excretion, the amount of urobilinogen in the urine is low.
I hope this helps!
Absolutely!
Posted by: at January 25, 2007 2:10 PMDamn, FC! That's exactly what I was going to say!
Posted by: at January 25, 2007 2:44 PM