Xunrui Hou ^1,2,3 Xin Liang ^2,3 Yuwei Lu ^2,3 Qian Zhang ⁴ Yujia Wang ⁵ Ming Xu ² Yuheng Luo ² Tongtao Fan ² Yiyi Zhang ² Tingting Ye ³ Kean Zhou ³ Jiahui Shi ³ Min Li ^1* Lihong Li ^2,3*

• ¹ Clinical Medical College of Acupuncture Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
• ² Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou Province, China
• ³ Guizhou Medical University, Guiyang, Guizhou Province, China
• ⁴ The Affiliated TCM Hospital of Guangzhou Medical University, Guangzhou, China
• ⁵ Weihai Hospital of Traditional Chinese Medicine Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Weihai, China

Acupoint Catgut Embedding (ACE) is an extended and developed form of traditional acupuncture that serves as a composite stimulation therapy for various diseases. However, its local stimulation effects on acupoints remain unclear. Acupuncture can activate mechanically sensitive calcium ion channels, TRPV2 and TRPV4, located on various cell membranes, promoting Ca 2+ influx in acupoint tissues to exert effects. Whether ACE can form mechanical physical stimulation to regulate these channels and the related linkage effect requires validation. This study investigates the influence of TRPV2 and TRPV4 ion channels on the local stimulation effects of ACE by embedding PGLA suture at the Zusanli (ST36) acupoint in rats and using TRPV2 and TRPV4 inhibitors. The results indicate that ACE using PGLA suture significantly increases the mRNA and protein expression of TRPV2 and TRPV4, Ca 2+ fluorescence intensity, and the expression of macrophage (Mac) CD68 and mast cell (MC) tryptase in acupoint tissues, with these effects diminishing over time. The increasing trends are reduced after using inhibitors, particularly when both inhibitors are used simultaneously. Furthermore, correlation analysis shows that embedding PGLA suture at the ST36 acupoint regulates Mac and MC functions through Ca 2+ signaling involving not only TRPV2 and TRPV4 but multiple pathways. These results suggest that embedding PGLA suture at the ST36 acupoint generates mechanical physical stimulation and regulates TRPV2 and TRPV4 ion channels, which couple with Ca 2+ signaling to form a linkage effect that gradually weakens over time. This provides new reference data for further studies on the stimulation effects and clinical promotion of ACE. Keywords：acupoint catgut embedding, mechanosensitive TRPV channel, Zusanli (ST36), local stimulation, Ca 2+ signaling.