黄颡鱼消化道不同部位6种重要酶的分布和组织定位

Distribution and histological localization of six essential enzymes along the different parts of digestive tract of Pelteobagrus fulvidraco

目的研究酸性磷酸酶(ACP)、碱性磷酸酶(ALP)、腺苷三磷酸酶(ATPase)、非特性酯酶(NSE)、过氧化物酶(POX)和琥珀酸脱氢酶(SDH)等6种重要酶在黄颡鱼消化道不同部位的分布与组织定位。方法在黄颡鱼消化道7个部位取材,采用冰冻切片、酶组织化学染色及光密度定量分析等技术。结果ACP在胃贲门、胃幽门和中肠酶活力较高,前肠和后肠次之,在食道和胃体酶活力明显较弱。ALP在食道、前肠和后肠酶活力较高,中肠其次,在胃贲门、胃体和胃幽门酶活力明显较弱。ATPase除在中肠酶活力明显较弱外,在消化道其他部位均检测到较高的酶活力。NSE和POX均以胃幽门酶活力最高,后肠酶活力较弱。SDH在前肠酶活力较高,胃贲门和胃体其次,在食道、胃幽门、中肠和后肠酶活力明显较弱。结论黄颡鱼消化道黏膜6种重要酶的分布与消化道各部位的生理功能相适应。黄颡鱼中肠是吸收蛋白质和细胞内消化的主要部位;前肠和后肠是吸收脂类、葡萄糖、钙和无机磷酸盐等重要营养物质的主要部位;胃幽门是脂质消化的主要部位。

Objective To investigate the distribution and histological localization of acid phosphatase(ACP),alkaline phospha-tase(ALP),adenosine triphosphatase(ATPase),non-speci fic esterase(NSE),peroxidase(POX)and succinate dehydrogenase(SDH)in the different parts of digestive tract of Pelteobagrus fulvidraco.Methods Tissue samples were taken from 7 parts of the digestive tract and investigated by frozen section,enzyme histochemical staining and quantitative analysis of optical density.Results ACP showed the highest enzyme activity in stomach cardia,stomach pylorus and middle intestine,followed by anterior intestine and posterior intestine,while enzyme activity was weaker in the esophagus and stomach corpus.ALP exhibited the highest enzyme activity in esophagus,ante-rior intestine and posterior intestine,followed by middle intestine,while the enzyme activity was signi ficantly lower in stomach cardia,stomach corpus and stomach pylorus.ATPase enzyme activity was high in the entire digestive tract except for the middle intestine.Both NSE and POX had the highest enzyme activity in stomach pylorus and lower enzyme activity in posterior intestine.SDH showed the highest enzyme activity in anterior intestine,followed by stomach cardia and stomach corpus,while the enzyme activity was obviously weaker in esophagus,stomach pylorus,middle intestine and posterior intestine.Conclusions The distribution of 6 essential digestive enzymes of Pelteobagrus fulvidraco was well adaptive to the physiological functions of various parts of the digestive tract.The middle intestine is the main site of protein absorption and intracellular digestion,the anterior intestine and posterior intestine are the main sites for absorbing important nutrients such as lipid,glucose,calcium and inorganic phosphate,the stomach pylorus is the main site of lipid digestion.