Objective

2

To screen and establish animal models of combined stasis and toxin syndrome based on the comparison of three modeling methods，

i.e

.， carrageenan （Ca）， Ca combined with dried yeast （Ca+Yeast）， and Ca combined with lipopolysaccharide （Ca+LPS）.

Method

2

Forty SPF male SD rats were randomly divided into normal group， Ca group， Ca+Yeast group， and Ca+LPS group， with 10 rats in each group. The Ca group， Ca+Yeast group， and Ca+LPS group received an intraperitoneal injection of Ca （10 mg·kg

-1

） on the first day. The Ca+LPS group received an intraperitoneal injection of LPS （50 μg·kg

-1

） on the second day， and the Ca+Yeast group received a subcutaneous injection of dry yeast suspension （2 mg·kg

-1

） on the back on the second day. The rectal temperature of each group was dynamically observed after modeling. After 24 hours of modeling， the macroscopic evaluation indexes， including tongue manifestation， pulse， and black tail length in each group were observed. The PeriCam PSI imaging system was used to detect the blood flow perfusion of the rat tail. The automatic hemorheology analyzer was used to measure the whole blood viscosity and plasma viscosity of each group. The PL platelet function analyzer was used to detect the platelet aggregation rate of the rats. The enzyme-linked immunosorbent assay （ELISA） was used to detect the interleukin-6 （IL-6） level in the rat plasma. The myocardial tissue， brain tissue， and lung tissue of each group of rats were observed by hematoxylin-eosin （HE） staining.

Result

2

Compared with the normal group， all three model groups showed varying degrees of black tail （

P

<

0.05，

P

<

0.01）， reduced blood flow perfusion at the tail end （

P

<

0.05，

P

<

0.01）， decreased R， G， and B values of tongue manifestation （

P

<

0.05，

P

<

0.01）， and increased maximum platelet aggregation rate （

P

<

0.05，

P

<

0.01）. The pulse amplitudes of the Ca+Yeast group and the Ca+LPS group were lower than that of the normal group （

P

<

0.05，

P

<

0.01）. In addition， the average rectal temperature of the Ca+Yeast group increased after 24 hours of modeling （

P

<

0.01）， and the low-， medium-， and high-shear whole blood viscosity and plasma viscosity increased （

P

<

0.05，

P

<

0.01） as compared with those in the normal group. Additionally， the expression level of the plasma inflammatory factor IL-6 was significantly up-regulated （

P

<

0.05）. Pathological morphology results showed that the Ca+Yeast group had the most severe pathological changes， with small foci of myocardial fiber dissolution， inflammatory cell infiltration， and fibroblast proliferation observed. In the hippocampal area， the neurons were sparse and had undergone red degeneration. In the small focus of the lung interstitium， lymphocytes and neutrophils were infiltrated.

Conclusion

2

The animal model of combined stasis and toxin syndrome was properly established using Ca+Yeast. The systematic evaluation system of the model， which includes traditional Chinese medicine four diagnostic information， western medicine microscopic indicators， and tissue pathological morphology， is worthy of consideration and reference by researchers.