The Effect Of Chaishao Chengqi Decoction On Nitric Oxide Synthase Neurons Of Intestinal Tract In Rats With Severe Acute Pancreatitis

Objective To investigate the changes of enteric nervous system on the gastrointestinal motility disorder in rats suffered from severe acute pancreatitis (SAP) and to investigate the influence of Chaishao Chengqi decoction on neuronal nitric oxide synthase (nNOS) expression of rat intestinal tract.Methods SD rats were randomly divided into 3 groups (10 for each): the sham operation group,the SAP model group and the group of SAP treated with Chaishao Chengqi decoction (CSCQD group). The SAP model group and CSCQD group were established by retrograde cholangiopancreatic duct injection of 50 g·L-1 sodium taurocholate. The SAP model group was administered gastric intubation with normal saline and the CSCQD group was administered gastric intubation with Chaishao Chengqi decoction. The abdominal X-ray and gastrointestinal transmit index(TI) were observed. The tissue of Pancreas was stained with HE and examined under light microscopy. The neuronal nitric oxide synthase neurons in the small intestine myenteric plexus,colonic myenteric plexus and colonic mucosa were detected by the dual immunofluorescent staining. Using reverse transcriptase polymerase chain reaction (RT-PCR), the expression levels of nNOS mRNA in ileum and colon were quantified.Results Compared with the sham operation group, intestine in the SAP model group was obvious expansion. Meanwhile transit index was decreased [(0.38±0.0179) vs(0.23±0.0156),p<0.05]. Compared with the SAP model group, intestine in the CSCQD group was not obvious expansion. Meanwhile transit index was increased [(0.51±0.0145)vs(0.23±0.0156)(p<0.05)]. Compared with the sham operation group, the abdomen in the SAP model group contained a large number of red or dark red turbid ascites and intestine was obvious expansion. Fat necrosis was found in mesenteric, greater omentum and peripancreatic tissue. Pancreas changes were hemorrhagic and necrotic. Histological scores of pancreatic tissue were significantly higher than that in the sham operation group[(1.7±0.7)vs(15.6±1.2)(p<0.05)]. Compared with the SAP model group, the quantity of ascites,the expansive degree of intestine and the degree of fat necrosis were significantly lessened in the CSCQD group . The pathologic lesion of the pancreas in CSCQD group was significantly lessened([15.6±1.2)v(s7.0±1.4)(p<0.05)]. Compared with the sham operation group, the size of the neuronal nitric oxide synthase neurons in the myenteric plexus of ileum and colon of the SAP model group was increased and nerve fibers were increased obviously. The percentage of NOS-immunoreactive neurons was significantly increased(p<0.05). Compared with the SAP model group, the size of the neuronal nitric oxide synthase neurons in the myenteric plexus of ileum and colon of the CSCQD group was decreased and nerve fibers were sparse. The percentage of NOS-immunoreactive neurons was significantly decreased(p<0.05). The percentage of NOS-immunoreactive neurons in the submucosal plexus of colon in three groups were no different(p>0.05). Compared with the sham operation group,nNOS mRNA expressions of ileum and colon of the SAP model group were increased(p<0.05). Compared with the SAP model group,nNOS mRNA expressions of ileum and colon of the CSCQD group were decreased(p<0.05).Conclusions Gastrointestinal dysmotility in rats with SAP is related to the increased expression of NOS neurons in ileus and colon. Chaishao Chengqi decoction improves the gastrointestinal motility in rats with SAP by reversing the plasticity of NOS-immunoreactive neurons and decreasing the nNOS mRNA expressions of ileum and colon then reduce the pathological damage of pancreatics .