Tauro α-muricholate is as effective as tauro β-muricholate and tauroursodeoxycholate in preventing taurochenodeoxycholate-induced liver damage in the rat



Male Wistar rats were infused intravenously with taurochenodeoxycholate (0.4 μmol/min/100 gm) alone (group A) or with one of the three bile salts (tauroursodeoxycholate [group B], tauro β-muricholate [group C] or tauro α-muricholate [group D]) at a rate of 0.2 μmol/min/100/gm for 1 hr. One-hour bile flow and bile salt excretion rates were significantly lower in group A than in the other three coinfused (B, C, D) groups. Biliary 1-hr outputs of lactate dehydrogenase and albumin in the bile, on the other hand, were significantly higher in group A than in the other groups. Plasma concentrations of lactate dehydrogenase at the time of killing (1 hr) were two to three times higher in group A than in the other groups. Although tauro α-muricholate does not possess a 7β-hydroxy group, the 6β-hydroxy group that tauro α-muricholate possesses thus appears to be as effective as a 7β-hydroxy group in reducing the liver damage caused by toxic bile salts such as taurochenodeoxycholate. The so-called hepatoprotective effects of tauroursodeoxycholate and tauro β-muricholate found in previous studies may require explanation(s) other than the presence of a 7β-hydroxy group in their molecular structures. (HEPATOLOGY 1994;19:1007–1012.)