Bilirubin and bile salts in relation to stones

[ChessMaster3000]

Disclaimer: this question is based of a UW item

In forming pigmented gallstones, am I correct in saying that bilirubin comes from chronic hemolysis, whereas the bile salts in the stones come from 7-a-hydroxylase formation in the liver? And further, that the formation of the bile salts tends to DECREASE the formation of the stones, as the bilirubin becomes more soluble? And finally, is all the bile in a pigment stone conjugated (via b-glucoronidase) or is there any unconjugated (I think not, just wanted to check)

Thanks!

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[MudPhud20XX]

Yup, I think so. I looked at FA and can confirm that

"Pigment stone (gallstone)s are seen in patients with chronic hemolysis, slcoholic cirrhosis, advanced age, and biliary infection. Black - hemolysis, Brown-infection."

Although I can't really see why brown would be an infection : (

Also, bile salts in the stone do come from the top regulated enzyme in the bile acid synthesis which as you stated is 7-a-hydroxylase. (Kaplan biochem also explains one important pharmacology relevant need to know: with cholestyramine, bile acids are secreted leading to increased 7-a-hydroxylase to make more bile acids thus consumes more cholesterol which in turn lowers the internal level of cholesterol in the hepatocytes.)

FA does say that increased cholesterol and bilirubin and decreased bile salts, and gallbladder stasis all cause stones. So I think you are right saying "bile salts tends to DECREASE the formation of the stones" as it probably contributes stones being more easily emulsified thus preventing the formation of gallstones perhaps?

I am not really sure about the association with the solubility of the bilirubin though.

I also want to say that the bile in the pigment stone is conjugated as in pathology associated with hyperbilirubinemias such as Dubin-Johnson syndrome, it's the conjugated bilirubin that contributes the blackness of the liver. But I could be wrong on this.