慢性砷中毒大鼠空肠中P物质、生长抑素表达与形态结构改变的关系．

Relationship between substance P, somatostatin expression and change of morphology structure in jejunumof arsenism rats

目的探讨慢性砷中毒对大鼠空肠P物质（sP）、生长抑素（SS）表达的影响及其与空肠形态结构变化的关系。方法将45只清洁级SD大鼠按性别和体质量随机分为对照（0．0mg·kg-1·d-1）、低砷（0．4mg·kg-1·d-1）、高砷（10．Omg·kg-1·d-1）组，每组15只。分别自由饮用砷（三氧化二砷，As203）含量为O、2、50mg／h的蒸馏水溶液，连续染毒4个月。采用HE染色、免疫组化链霉亲和素一生物素复合物（SABC）法光镜下观察空肠形态结构变化及SP、SS阳性细胞数．Biomias图像分析软件测定SP、SS阳性细胞平均灰度值。结果光镜下，慢性砷中毒大鼠部分空肠绒毛不规则；部分纹状缘脱落，不整齐；杯状细胞增多；固有层内炎性细胞浸润；小肠腺部分细胞出现空泡。3组大鼠空肠SP、SS阳性细胞计数比较，差异有统计学意义（F值分别为608．54、227．59，P均〈0．05），其中低、高砷组[（1．85-I-0．25）、（1．83±0．24）个／视野和（4．24±0．33）、（3．31±0．41）个／视野]明显高于对照组[（0．94±0．21）、（1．14±0．14）个／视野]，且高砷组明显高于低砷组（P均〈0．05）。3组大鼠空肠SP、SS阳性细胞平均灰度值比较，差异有统计学意义（F值分别为68．43、26．57，P均〈0．05），其中低、高砷组（125．13±2．35、131．28±5．66和118．30±4．58、124．03±3．94）明显低于对照组（133．76±3．61、137．57±5．49），且高砷组明显低于低砷组（尸均〈0．05）。结论慢性砷中毒大鼠空肠黏膜损伤及形态结构改变与SP、SS表达上调有关。

Objective To explore the relationship between substance P（SP）, somatostatin（SS） expression and change of morphology structure in jejunum of arsenism rats. Methods Acoording to sex and body mass, forty five clean grade SD rats were divided into control （0.0 mg. kg-1·d-1）, low-dose arsenic （0.4 mg.kg-1·d-1 ） and highdose arsenic（10.0 mg.kg-1·d-1） groups, n = 15. The rats in low- and high-dose groups were treated with As203（2, 50 mg/L） through drinking water for 4 months, respectively. Morphology changes of jejunum were observed by histological technique-HE staining and SABC immunohistochemistry. SP and SS positive cells in the jejunum were observed and counted, and its average gray value was analyzed with image analysis software （Biomias）. Results Some jejunal villi were irregular in arsenism rats; with some brush border loss and irregular; goblet cells increased; infiltration of inflammatory cells in the lamina propria; and vacuoles in some intestinal gland cells. The differences of SP and SS positive cells between groups were statistically significant （F = 608.54, 227.59, all P 〈 0.05）. Compared with the control group （0.94 ± 0.21, 1.14 ± 0.14）, SP and SS positive cells in low- and high- dose arsenic groups（1.85± 0.25, 1.83 ± 0.24 and 4.24 ± 0.33, 3.31 ± 0.41） were significantly higher（all P 〈 0.05）, and high-dose arsenic group was significantly higher than the low-dose arsenic group （all P 〈 0.05）. The differences of average gray values of SP and SS positive cells between groups were statistically significant （F = 68.43, 26.57, all P 〈 0.05）. Compared with the control group（133.76 ± 3.61, 137.57 ± 5.49）, SP and SS positive cells in low-and high-dose arsenic groups（125.13 ± 2.35, 131.28 ± 5.66 and 118.30 ＋ 4.58, 124.03 ± 3.94） were significantly lower（all P 〈 0.05）, and high-dose arsenic group was significantly lower than the low-dose arsenic group（all P 〈 0.05）. Conclusions Up-regulation of SP, SS may be related to jejunal mucosal injury and morphology structure in arsenic poisoning rats.