acetic acid writhing test的用法和样例：
- The analgesic effect was determined with the models of acetic acid writhing.
- Zuotongning injection can obviously inhibit the writhing action induced by acetic acid and enhance the analgesic effect induced by the hot-plate test in mice.
- Results: 1) PPL could dose-dependently raise the pain threshold in tail stimulation-vocalization test in rats and inhibit the writhing reaction induced by acetic acid in mice.
- Methods: The method of writhing by acetic acid, hot-plate and electric stimulation in mice were made to study the analgesic effect of HE extract.