Study The Effects Of PSCs, Inflammtory Cells, And PDGF-B, TGF-β1, CTGFmRNA On The Pathogenesis And Progression Of CP And Their Correlations

Backgrand: Chronic pancreatitis (CP) is one of the chronic disease in the whole world, it's pathogenesis is not certainly clear. Today, we still have no specific diagnostic methods and effective therapeutic measures. Previous research found that CP could induce pancreatic carcinoma through the stage of pancreatic intraepithelial neoplasia (PanIN). Since 1997, the year of found and cultivated pancreatic stellate cell (PSC), considerable research showed that activation of PSC was the key process of the pathogenesis of pancreatic fibrosis. It is of great importance to research on mechanism of PSC's activation and regulative factors.Objective: To study the effects of PSC, inflammatory cells, and PDGF-B, TGF-β1, CTGF mRNA on the pathogenesis and progression of CP and their correlations.Methods: Fifty-three cases tissues of chronic pancreatitis and seven ones tissues of normal pancreas were invested in the experiments. We inspected and scored the pathological changes by microscopy, determined the area percentage of pancreatic fibrosis by Van Gieson's staining, counted mast cells by toluidine blue staining. Macrophages and a-SMA were stained by streptavidin-peroxidase(SP) immumohistochemical method. PDGF-B mRNA, TGF-β1 mRNA and CTGF mRNA were stained by in situ hybridization. The method of counting positive cells of mast cells, macrophages and PSCs was selecting five high power fields of microscopy every slide, getting mean number as the count of the silde. Expression area percentages and gray scal values were gotten from the analysis of computer medical analyze system.Results: (1) Fibrosis degree: The fibrosis areas in CP groups were higher than that in normal group (P＜0.01 or P＜0.05), fibrosis areas in middle and severe CP groups were higer than that in slihgt CP group (P＜0.01 or P＜0.05), fibrosis area in severe CP group were higher than that in middle CP group (P＜0.05).(2) Expression of a-SMA: The counts of a-SMA positive cells in CP groups were higher than that in normal group (P＜0.01 or P＜0.05), positive a-SMA count in severe CP group was obviously higer than those in slihgt and middle CP groups (P＜0.01 or P＜0.05). The mean munbers of gray scale values of a-SMA positive expression cells in CP groups were obviously higher than that in normal group (P＜0.01).(3) Mast cell and macrophage counts: The counts of mast cells in CP groups were significantly higher than that in normal group (P＜0.01), mast cells counts in middle and severe CP groups were higher than that in slight CP group (P＜0.05). There was no significant difference of macrophages counting among all the groups (P＞0.05).(4) Expression of PDGF-B mRNA: The positive expression areas of middle and severe CP groups were higher than that of normal group (P＜ 0.01 or P＜0.05), mean value of positive expression area in severe CP group was obviously higer than those in slight and middle CP groups (P＜0.01). Mean gray scale values of positive expression cells in CP groups were all obviously higer than that in normal group (P＜0.01). Scores in CP groups significantly higer than that in normal group (P＜0.01), score in severe CP group was higer than those in slight and middle CP groups (P＜0.01 or P＜0.05).(5) Expression of TGF-β1 mRNA: The positive expression areas ofmiddle and severe CP groups were higher than that of normal group (P＜0.01 or P＜0.05), mean value of severe CP group positive expression area was obviously higer than those in slight and middle CP groups (P＜0.01). Mean gray scale values of positive expression cells in CP groups were all obviously higer than that in normal group (P＜0.01). Scores in CP groups significantly higer than that in normal group (P＜0.01), score in severe CP group was higer than those in slight and middle CP groups (P＜0.01 or P＜0.05).(6) Expression of CTGF mRNA: The positive expression areas of CP groups were higher than that of normal group (P＜0.01 or P＜0.05), mean value of severe CP group positive expression area was obviously higer than that in slight CP group (P＜0.01). Mean gray scale values of positive expression cells in CP groups were all obviously higer than that in normal group (P＜0.01). Scores in CP groups significantly higer than that in normal group (P＜0.01), score in severe CP group was higer than that in slight CP group (P＜0.05).(7) Correlation analysis: There were closely positive correlations among the pathological degree, fibrosis degree, a-SMA positive cells counts, mast cells counts, positive expression areas and scores of PDGF-B mRNA, TGF-B1 mRNA, CTGF mRNA (P＜0.01). Positive correlations were found between gray scale value of a-SMA positive cells and those of PDGF-B mRNA, TGF-β1 mRNA and CTGF mRNA positive cells, fibrosis area, macrophages counts (P＜0.01 or P＜0.05). There were positive correlations between PDGF-B mRNA positive cells' gray scale value and that of CTGF mRNA, pathological degree, fibrosis area, mast cells and macrophages counts (P＜0.01 or P＜0.05). There were closely positive correlations between TGF-β1 mRNA positive cells' gray scale value and that of CTGF mRNA, pathological degree (P＜0.01). Closely positive correlations were found between gray scale value of CTGF mRNA positive cells and pathological degree, fibrosis area (P＜0.01). There were high consistency among experssion areas and scores of PDGF-B mRNA, GF-β1 mRNA, CTGF mRNA (P＜0.01).Conclusion: Pancreatic fibrosis was the very important and the most significantly pathological changes in CP. Activation of PSCs was key process of the pathogenesis and devolopment of pancreatic fibrosis. The infiltrations of mast cells and macrophages in CP tissues have relationships with pathological degrees. Expression levels of PDGF-B, TGF-β1 and CTGF might have important effects on pathogenesis and devolopment, fibrosis and activation of PSCs. There were closely correlationships among these cytokines, they were main activators of PSCs in chronic pancreatitis.