Relationship between farnesoid X receptor and liver regeneration of obstructive jaundice rats following partial hepatectomy with different biliary drainages

Abstract

Objective To evaluate the relationship between farnesoid X receptor (FXR) and liver regeneration of obstructive jaundice (OJ) rats following partial hepatectomy (PH) with different biliary drainages.Methods 120 male Sprague-Dawley rats were randomly allocated into 4 groups:control group,normal rats subjected to PH (70％ hepatectomy) ; OJ group,OJ rats without drainage subjected to PH; internal drainage (ID) group,OJ rats with ID subjected to PH; external drainage (ED) group,OJ rats with ED subjected to PH.The expression of FXR mRNA and protein and cholesterol 7α-hydroxylase (CYP7A1)mRNA in liver tissue,and total bile acid (TBA) content in the blood were examined at0,4,12,24,48,72 h after operation.Results The positive rate of proliferating cell nuclear antigen (PCNA) [(19.52 ±1.87)％,(30.16 ±2.65)％,(46.44 ±2.66)％,(44.36 ±3.82)％] during 12 to 72 h after PH in ED group was obviously lower than that in control and ID groups (P ＜ 0.05).The TBA content in ED group [(20.38±4.33),(25.87 ±8.68),(35.05 ±6.87),(49.66±6.65),(60.44±7.66),(52.36±8.82) μmol/L] during 0 to 72 h after PH was obviously lower than that in control and ID groups (P＜0.05).The relative quantitative expression of CYP7A1 mRNA in ED group (1.75 ±0.09,1.68 ±0.14,1.53 ±0.16,1.25 ±0.16,1.17 ±0.18,1.24 ±0.16) during 0 to 72 h after PH was obviously higher than that in control and ID groups (P ＜ 0.05).The relative quantitative expression of FXR mRNA in ID group [(1.52±0.18),(1.80±0.12),(1.89±0.12),(2.56 ±0.09),(2.39 ±0.20),(2.02 ±0.24)] during 0 to 72 h after PH was obviously higher than that in ED group (P ＜ 0.05).The expression of FXR protein was corresponded with FXR mRNA generally.There was no statistically significant difference between ID and control groups in each index (P ＞ 0.05).Conclusion The inhibition of the liver regeneration in the OJ rats after PH with ED versus ID is related with the reduction in the bile acid pool size,which may be caused by the down-regulation of FXR expression. Key words: Cholesterol 7α-hydroxylase ; Bile acid ; Farnesoid X receptor; Liver regeneration