Cold Storage Injury to Rat Small-bowel Transplants-Beneficial Effect of a Modified HTK Solution

Area of Science:

• Transplantation immunology
• Vascular surgery
• Gastroenterology

Background:

• Small bowel transplantation is threatened by cold ischemic injury during graft transport.
• The small bowel's mucosal microcirculation is particularly vulnerable to ischemic damage.
• Current preservation solutions like histidine-tryptophan-ketoglutarate (HTK) are outdated and do not fully address hypoxia or free radical damage.

Purpose of the Study:

• To develop and evaluate a modified HTK preservation solution to mitigate cold ischemic injury in small bowel grafts.
• To assess the impact of specific components like glycine, alanine, and iron chelators on microcirculatory function post-transplant.

Main Methods:

• A heterotopic, syngeneic rat small bowel transplantation model was used.
• A modified HTK solution incorporating glycine, alanine, and iron chelators was tested.
• Intravital microscopy assessed microcirculatory parameters during early reperfusion, comparing modified vs. conventional HTK solutions.

Main Results:

• Glycine alone showed a slight improvement in mucosal perfusion.
• The modified base solution and iron chelators individually enhanced mucosal functional capillary density.
• The complete modified solution significantly improved perfusion index, functional capillary density, and red blood cell velocity post-reperfusion.

Conclusions:

• The modified preservation solution effectively enhances small bowel transplant microcirculation.
• This improved solution warrants further investigation in diverse small bowel transplantation models.