【Animal modeling】-The application of mouse regional lymph node assay (BrdU-ELISA) in the detection of skin sensitization of 25% Cyhalofop-ethyl EC

  OBJECTIVE: To detect the sensitization of 25% Cyhalofop-ethyl EC by mouse regional lymph node assay (BrdU-ELISA).

  Methods: 1. Select female BALB/C mice for experiment, the test samples are set as 100%, 50%, 25%, and the negative control group [acetone: olive oil (AOO) = 4: 1], The negative control group (olive oil) and the positive control group (25% hexyl cinnamaldehyde) were exposed to the back of both ears for 3 days, and BrdU solution (5 mg per animal) was intraperitoneally injected on the 6th day, and the retroauricular lymph nodes were collected 24 hours later. Weighing, etc., and detecting lymphoid proliferation by BrdU-ELISA assay.

  Results: There was no significant difference in the body weight of mice in each dose group compared with the control group (P>0.05); the increase in ear thickness and ear weight in each dose group did not exceed 25%; the stimulation index SI1 of the solvent and blank control groups and SI2<1.6, the="" stimulation="" index="" si1="" si2="">1.6 of the positive control group (25% hexyl cinnamaldehyde), the experimental system is reliable; the stimulation index SI1 and 25% Cyhalofop-ethyl EC low, medium and high dose groups SI2<1.6, no dose-response relationship.

  Conclusion: The regional lymph node test results of 25% Cyhalofop-ethyl EC were negative, that is, 25% Cyhalofop-ethyl EC was non-sensitizing.