OBJECTIVETo study the effect of Modified Dachengqi Decoction (MDD) as whole course therapy on mediators of inflammation in severe acute pancreatitis (SAP) model rats, and to compare interventional advantages over intestinal mucosal barrier (IMB) of SAP rats between whole course therapy of MDD and early stage therapy of MDD.

METHODSTotally 190 SD rats were divided into five groups according to random digit table, i.e., the sham-operation group, the model group, the octreotide (OT) group, the early stage MDD treatment group, the whole course MDD treatment group, 38 in each group. SAP models were established with retrograde injection of 5% sodium taurocholate into the pancreaticobiliary duct. Three hours after modeling normal saline (NS) was administered to rats in the sham-operation group and the model group by gastrogavage, once per 12 h.1.35 µg/100 g OT was subcutaneously injected to rats in the OT group, once every 8 h. 0.4 mL/100 g MDD was administered to rats in the early stage MDD treatment group, and 6 h later changed to NS (once per 12 h).0.4 mL/100 g MDD was administered to rats in the whole course MDD treatment group, once every 12 h. The accumulative survival rate and morphological manifestations of pancreas and small intestine were observed under microscope 48 h after modeling. Pathologic scores of the pancreas and small intestine were conducted at 4, 6, 24, and 48 h after modeling. Contents of serum amylase (AMY), alanine transaminase (ALT), and TNF-α were also detected. The expression of high mobility group box protein 1 (HMGB1) in the small intestine tissue was also detected by Western blot. The positive rate of bacterial translocation in mesenteric lymph nodes (MLNs) was observed within 48 h. Correlations between serum TNF-α or HMGB1 in small intestinal tissue and pathological scores of the pancreas or the small intestine were analyzed.

RESULTSThe accumulative survival rate was 100. 0% in the sham-operation group, 79. 2% in the whole course MDD treatment group, 70. 8% in the OT group, 45. 8% in the early stage MDD treatment group, and 37.5% in the model group. At 6 h after modeling, pathological scores decreased more in the whole course MDD treatment group, the early stage MDD treatment group, the OT group than in the model group (P < 0.05). At 24 and 48 h after modeling, pathological scores of the pancreas and the small intestine decreased more in the whole course MDD treatment group and the OT group than in the early stage MDD treatment group (P <0. 05). At 6, 24, and 48 h after modeling, serum contents of AMY and ALT both decreased more in the whole course MDD treatment group, the early stage MDD treatment group, the OT group than in the model group (P < 0.05). At 48 h after modeling serum contents of AMY and ALT both decreased more in the whole course MDD treatment group and the OT group than in the early stage MDD treatment group (P < 0.05). At 6 h after modeling serum TNF-α levels decreased more in the whole course MDD treatment group, the early stage MDD treatment group, the OT group than in the model group (P < 0.05). At 6, 24, and 48 h after modeling the level of HMGB1 in the small intestinal tissue decreased more in the whole course MDD treatment group, the early stage MDD treatment group, the OT group than in the model group (P < 0.05). Of them, HMGB1 levels at 24 and 48 h were lower in the whole course MDD treatment group and the OT group than in the early stage MDD treatment group (P < 0.05). The number of MLNs bacterial translocation at 48 h after modeling was lower in the whole course MDD treatment group and the OT group than in the early stage MDD treatment group and the model group (P < 0.05). Serum TNF-α contents within 6 h were positively correlated with pathological scores of pancreas (r = 0.579, P < 0.01). ROC curve showed that serum TNF-α contents could predict the severity of SAP (ROC = 0.990, 95% Cl: 0.971 to 1.000). HMGB1 in the small intestine was positively correlated with pathological scores of the small intestine (r = 0.620, P < 0.01).

CONCLUSIONSEarly stage use of MDD could effectively reduce the release of TNF-α, while whole course use of MDD could effectively inhibit the expression of HMGB1. The latter could preferably attenuate injuries of the pancreas and the small intestine, lower MLNs bacterial translocation, and elevate the survival rate.