促纤维化细胞因子在纤维化胰腺组织中的表达

Expression of profibrotic cytokines in the process of chronic pancreatitis

目的 揭示转化生长因子 (TGF) β1、结缔组织生长因子 (CTGF)在慢性胰腺炎的动物模型中的表达情况及其与胰腺纤维化的相关性。方法 采用Puig Divi等方法制备慢性胰腺炎大鼠模型 (模型组 ) ,制模后的 3、4、5和 6周取胰腺组织 ,对照组则在 4周取材。分别作苏木精 伊红染色、免疫组织化学 [纤维连接蛋白(FN)、Ⅰ型胶原 (COL Ⅰ )、TGF β1、CTGF]和原位杂交染色 (TGF β1、CTGF)。结果 模型组于 3周后可见局部胰管扩张、胰腺间质纤维组织轻度增生、炎症细胞浸润和腺泡细胞空泡样变 ,小叶内腺泡细胞有局限性纤维化或无变化。 4周时胰管显著增生 ,胰管周围及小叶间和小叶内纤维化伴炎症细胞浸润 ,局部腺体萎缩代之以纤维瘢痕组织。而 5、6周时胰腺纤维化程度与 4周时比较并未见明显增强。免疫组织化学结果显示 ,TGF β1主要分布于间质区成纤维细胞细胞质、间质基质区和炎性细胞浸润区。CTGF分布于腺上皮细胞的细胞质和部分间质成纤维细胞中。原位杂交显示TGF β1mRNA及CTGFmRNA分布部位与免疫组织化学结果相吻合。此外 ,TGF β1、CTGF与代表纤维化严重程度的FN、COL Ⅰ的分布及表达基本相同并成正相关 (P <0 .0 5 )。对照组在4周时仅见脂肪组织浸润。所有结果 3、4两周的差异有显著性 (P <0 .0 1) ,4、

Objective To reveal the correlative association of pancreatic expression of TGF β 1 and CTGF in chronic pancreatitis animal model. Methods The injection method of TNBS through rats' pancreatic duct was undertaken to set up the animal model of chronic pancreatitis; Col1 and FN were taken as the markers of matrix synthesis to evaluate the degrees of severity of pancreatic fibrosis by using immunohistochemistry in situ for hybridization. TGF β 1 and CTGF were also investigated by these methods to detect their pancreatic expression at the levels of transcription and translation with their mRNA and protein expressions. Results Injection of TNBS solution into rats' pancreatic duct caused changes such as duct dilatation, interstitial edema, infiltration of inflammatory cells and acinar cellular necrosis in the pancreatic tissue 3 weeks after wards. By the end of 4 weeks, the changes reached the peak level with formation of pancreatic fibrosis with no further increase in the degree of fibrosis later on. TGF β 1 was detected in the cytoplasm of the fibroblasts in the interstitial and some inflammatory areas with intensive expression of CTGF disseminating in the acinar epithelial cells and a portion of fibroblasts. The expression intensity of TGF β 1 and CTGF were corqrelated to the grade of fibrosis ( P <0.01).Conclusions The increasing level of pancreatic fibrosis formation is positively correlated with the expressions of TGF β 1 and CTGF, especially the CTGF as the downstream factor of TGF β 1, may play a key role in the processing.