3种染料在小鼠胃肠推进试验中的运用

Application of Three Kinds of Dyes in Gastrointestinal Propulsion in Mice

为了筛选胃排空和肠推进试验最佳示踪染料,本试验选取葡聚糖蓝2000、伊文思蓝和墨汁3种染料,用微量倍比稀释法测定一系列浓度各染料在一系列波长的吸光度值,以确定各染料的最大吸收波长和可测浓度范围。根据各染料可测范围确定小鼠最佳灌胃剂量,测定各染料在胃残留率、小肠推进率及小肠均4段各段染料残留率,确定各染料在消化道总残留率。结果显示,在本试验测定波长中,葡聚糖蓝2000、伊文思蓝和墨汁最大吸收波长分别630、630和405nm;可测浓度范围分别为0.16~5.00mg/mL(R^2=0.9863)、0.78~6.25μg/mL(R^2=0.9984)和0.02%~0.16%(R^2=0.9979)。3种染料对胃排空率的影响差异不显著(P>0.05),而肠推进率伊文思蓝显著快于其他两种染料(P<0.05);3种染料总残留率葡聚糖蓝2000最高,其次为墨汁,伊文思蓝最低,分别为93.6%±4.5%、71.5%±8.5%和18.7%±2.8%。本试验结果提示,在检测受试物对在体消化道运动影响研究中,如果仅要求测定肠推进率可用墨汁,如果要精确检测胃和小肠各段排空情况则用葡聚糖蓝2000为宜。

In order to select the best tracer dye for gastric emptying and intestinal propulsion ex-periment,three kinds of dyes including of dextran blue 2000,direct blue 53 and ink were selected. The absorbance values of the series of concentration of dyes were tested in a range of wavelength by micro double dilution method.Moreover,the maximum absorption wavelength and measurable concentration range of three dyes were determined.According to measurable range of three kinds of dyes,the optimal gavage doses were obtained in mice.The gastric residual rates,small intestinal propulsion rates and residual rates in four parts of equal small intestine were tested.The results showed that the maximum absorption wavelengths of dextran blue 2000,direct blue 53 and ink were 630,630 and 405 nm,respectively.Their measurable concentration ranges were 0.16 to 5.00 mg/mL （R^2=0.9863）,0.78 to 6.25 μg/mL （R^2=0.9984）and 0.02% to 0.16% （R^2=0.9979）.The difference of gastric emptying rates among the three dyes was not significant （P〉0.05）,and intestinal propulsion rate of direct blue was significantly higher than those of the other two dyes （P〈0.05）.Total residual rates of dextran blue 2000,ink and direct blue were 93.6%±4.5%,71.5%±8.5% and 18.7%±2.8%,respectively.The results suggested that ink was the best tracer dye if only the intestinal propulsion rate invivo needed to be determined,while dextran blue 2000 is appropriate if a precise determination of the gastric and intestinal emptying needed to be done.