- K T Mok: Department of Surgery, Veterans General Hospital-Kaohsiung, National Yang-Ming University, Taiwan.
This study investigates the importance of intestinal bile flow in cellular immunity. Sprague-Dawley rats undergoing bile duct ligation (BDL) and sham ceiliotomy (Sham) for 14 and 21 days were investigated. Experimental animals following BDL were further divided into an external drainage (ED) group, an ED group with rat chow mixed with 2:2:1 cholic acid, chenodeoxycholic acid, and deoxycholic acid (ED + BF), and an internal drainage (ID) group. Fourteen days later, they were killed and analyzed for spleen lymphocytic [3H] thymidine uptake (LHU) under mitogen stimulation with phytohemagglutinin, blood biochemistry, hemogram, and liver pathology. In the 14-day BDL experiment, LHU and serum albumin level were decreased in the BDL group (P < 0.05). After drainage, they were not significantly different among sham, ED, ED + BF, and ID groups. In the 21-day BDL experiment, the red cell volume was decreased (P < 0.05). After drainage, the ED, ED + BF, and ID groups still had a significantly lower LHU than the sham group (P < 0.05). However, the ID group had higher LHU than the ED and ED + BF groups (P < 0.05). The ED + BF group had a slightly higher LHU than the ED group but not statistically significant. Liver pathology returned to normal after drainage in the 14-day BDL model. In contrast, the 21-day BDL group had prominent periportal necrosis and developed periportal fibrosis after drainage. The present study reveals the duration of BDL determines the severity of hepatic damage. In the 14-day BDL groups, all kinds of drainage completely reverse the impaired liver function and cellular immunity. In the 21-day BDL group, 14-day drainage is inadequate for recovery because irreversible pathological changes are found. The reversal of cellular immunity in ID is better and faster, because it provides a better hepatic functional, nutritional, and hematological recovery besides the presence of primarily secreted bile acids.