The effect of chenodeoxycholic acid feeding on bile acid kinetics and fecal neutral steroid excretion in patients with hyperlipoproteinemia types II and IV.

The kinetics of 24-14C-cholic acid and 3H-chenodeoxycholic acid and the elimination of cholesterol as fecal neutral steroids were studied in 6 patients with Type II and 7 patients with Type IV lipoprotein pattern before and during the ingestion of 0.8 to 1.0 Gm. of chenodeoxycholic acid per day. During treatment, the pool size of chenodeoxycholic acid increased in all subjects (not studied in one Type IV patient). In Type II patients, this effect was associated with a decrease of the cholic acid pool size from 868 +/- 141 to 213 +/- 51 mg. and of the cholic acid synthesis from 204 +/- 36 to 54 +/- 20 mg. per day. In the patients with hyperlopoproteinemia Type IV, the cholic acid pool size diminished in 6 of the 7 subjects all of whom showed a decrease in the cholic acid synthesis on the average from 607 +/- 155 to 202 +/- 44 mg. per day. It is suggested that the feedback control of cholic acid synthesis is less sensitive in the Type IV than in the Type II patients. Chenodeoxycholic acid feeding did not influence the fecal excretion of cholesterol, coprostanol, and coprostanone in a consistent way.