# Effects of Tongmai oral liquid in femoral ateriovenous fistula

## TL;DR

Tongmai oral liquid improves femoral arteriovenous fistula function in rabbits by increasing blood flow and reducing thrombosis.

## Contribution

This study demonstrates that Tongmai oral liquid enhances fistula maturation without regulating NO and ET-1 balance.

## Key findings

- Tongmai oral liquid reduced fistula thrombosis and improved tissue adhesion.
- Fistula stoma blood flow was higher in Tongmai-treated rabbits compared to control and Aspirin groups.
- Tongmai did not regulate the NO and ET-1 equilibrium but still improved function.

## Abstract

This study was conducted to investigate the protective effect of Tongmai oral liquid on arteriovenous fistula function and to provide an effective method to promote fistula maturation.

Fifteen female and fifteen male SPF New Zealand rabbits were randomly allocated into 3 groups including control, Aspirin and Tongmai oral liquid groups. A side-to-side femoral arteriovenous fistula was established in each rabbit and then animals were treated with Aspirin or Tongmai oral liquid for 2 weeks. The concentrations of circulating ET-1 and NO were determined before and after operation (on preoperative day, operative day, post-D1, post-D3, post-D7 and post-D15), respectively. Blood flow of the fistula stoma and contralateral artery and vein was determined on the 15th postoperative day. Last, the fistula stoma was dissected to observe patency, thrombosis and adhesion with surrounding tissues.

28 rabbits survived during the surgical process and the following 15-day observational period. Tissue adhesion of arteriovenous fistula with surrounding tissues was improved and fistula thrombosis was reduced by treatment with Tongmai oral liquid. NO concentration decreased to a different extent after vascular surgery. Tongmai oral liquid failed to regulate the equilibrium between NO and ET-1, but it improved blood flow of fistula stoma, as compared to control and Aspirin groups. Blood flow of fistula stoma in the three groups was lower than that of the contralateral femoral artery.

Tongmai oral liquid improved the function of femoral ateriovenous fistula in the rabbit model by increasing blood flow and reducing thrombosis, probably not by regulating the dynamic equilibrium between NO and ET-1.