From the perspective of traditional Chinese medicine (TCM), most antibiotics possess the properties of clearing heat and detoxification with a bitter and cold nature. They can clear heat, purge fire and eliminate toxins; bitterness can dry dampness, while excessive drying injures yin, and cold nature impairs yang. Long-term and overuse of such agents leads to yin consumption, dysfunction of gastric reception, insufficiency of spleen qi (yang), and impaired transportation and transformation, eventually resulting in diarrhea. Coptis chinensis is extremely cold in property, and long-term excessive administration easily damages the spleen and stomach. In this experiment, two combined antibiotics were used to induce intestinal flora imbalance, followed by intervention with Coptis chinensis decoction to establish a spleen deficiency-cold diarrhea model. Body weight, stool characteristics and colonic histopathological changes of animals before and after modeling were detected to verify the successful establishment of the spleen deficiency-cold diarrhea model.

Wistar rats (male, 260–300 g)
Modeling method: Double antibiotics were administered by intragastric gavage daily for 3 consecutive days to induce intestinal flora imbalance. After antibiotic treatment, Coptis chinensis decoction was given intragastrically every day for 7 consecutive days to successfully establish the spleen deficiency-cold syndrome model.
Evaluation indexes: body weight measurement, HE staining

Body weight measurement

HE staining of colonic tissue