Related Experiment Videos
Bradykinin receptor modulation in vein grafts
1Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710.
Summary
Vein grafting alters bradykinin receptor responses. Arterialization and surgery reduce B2 receptor activity, while surgery alone increases B1 receptor activity, indicating distinct graft adaptation mechanisms.
Area of Science:
- Vascular biology
- Pharmacology
- Surgical research
Background:
- Vein grafting leads to altered bradykinin B2 and B1 receptor responses.
- The causes of these receptor changes (nonspecific effects, inflammation, hemodynamics) are unclear.
Purpose of the Study:
- To differentiate the mechanisms behind bradykinin receptor alterations in vein grafts.
- To investigate the roles of surgical procedure and arterialization in these changes.
Main Methods:
- Studied four experimental tissue models in New Zealand White rabbits.
- Harvested vein grafts and native veins at 28 days postoperatively.
- Performed isometric tension studies measuring responses to bradykinin (B2 agonist) and des-Arg9-bradykinin (B1 agonist).
Main Results:
- Progressive attenuation of B2 receptor sensitivity (bradykinin) was observed in native veins, bypass grafts, and arterialized grafts.
- Development of B1 receptor sensitivity (des-Arg9-bradykinin) occurred in native veins and both graft types.
- B2 receptor changes linked to surgery and arterialization; B1 receptor changes linked to nonspecific operative effects.
Conclusions:
- Two distinct mechanisms modulate bradykinin receptors in vein grafts post-implantation.
- Surgical procedure and arterialization contribute to B2 receptor alterations.
- Nonspecific sensitization from surgery drives B1 receptor changes.