大鼠被动皮肤过敏反应实验条件的优化

摘要

目的：通过卵白蛋白（OVA）致敏大鼠优化被动皮肤过敏反应（PCA）的实验条件。方法1~2月龄SD大鼠ip给予OVA（每只0.2，1.0和5.0 mg）与弗氏完全佐剂的混合乳液，隔日1次，共3次，进行致敏。分别于末次致敏后1，3，5，7，10，12，14，16和18 d用ELISA检测血清总IgE（T-IgE）水平和OVA特异性IgE （OVA-sIgE）水平。大鼠致敏后12~16 d制备致敏血清。大鼠皮内注射致敏血清被动皮肤致敏后，于0.5，1.5，3，6，12，24，36，48和60 h后iv给予同等剂量OVA和伊文思蓝激发，于激发后10，30和60 min测量大鼠皮肤蓝斑直径。结果 OVA致敏大鼠血清T-IgE和OVA-sIgE水平分别于末次致敏后3~7 d和12~16 d达高峰；在OVA 0.2~5.0 mg剂量范围内，OVA-sIgE与T-IgE水平无明显关联性；OVA 1.0和5.0 mg致敏大鼠血清能诱发大鼠PCA；皮内注射致敏血清0.5~3 h后激发的皮肤蓝斑形态规则，范围最大；激发后30~60 min检测的皮肤蓝斑范围大，界线清晰，形状规则，且着色较深。结论 PCA优化条件为1~2月龄大鼠隔日每只ip给予OVA 1.0~5.0 mg，共致敏3次，致敏后12~16 d制备致敏血清。在被动皮肤致敏0.5~3 h后，进行激发，30~60 min后检测皮肤内层蓝斑直径。%OBJECTIVE To optimize the parameters of passive cutaneous anaphylaxis(PCA)in rats immunized by ovalbumin(OVA). METHODS 1-2 month-old Sprague-Dawley rats were immu⁃nized by ip injection of OVA(0.2,1.0 and 5.0 mg per rat)mixed with complete Freund′s adjuvant once every other day 3 times. Serum was collected on the 12th-16th days after final immunization. Then the rats were intracutaneously injected with sensitized serum and then stimulated by iv injection of the same dose of OVA mixed with Evans blue after a latent period of 0.5,1.5,3,6,12,24,36,48 and 60 h. Finally,the diameters of blue spots in the skin were measured at stimulation. RESULTS Serum total-IgE(T-IgE)and OVA-specific IgE(sIgE)levels increased significantly and reached the peak on the 3rd-7th days and 12th-16th days after final immunization,respectively. There was no correlation between the serum T-IgE level and OVA-sIgE level when the rats were immunized with OVA at OVA 0.2-5.0 mg per rat. The rats experienced PCA after injection of OVA 1.0 and 5.0 mg per rat. Diameters of blue spots in the skin reached the maximum value after rats were sensitized for 0.5-3 h. Moreover,the shape,color and size of blue spots were better 30-60 min after stimulation. CONCLUSION Optimized PCA is as follows:1-2 month-old rats are immunized on the 1st,3rd and 5th days by ip injection of OVA 1.0-5.0 mg. The immunizing serum is collected at 12-16 d after final immunization. The rats are stimulated by OVA and Evans blue after a latent period of 0.5-3 h. Diameters of blue spots in rats′ skin are then measured 30-60 min after stimulation.