Plasma and mucosal histamine after small bowel transplantation in rats

During the course of a study on preservation of small bowel transplants in rats, the hypothesis that histamine may play a role in graft damage has been investigated. Plasma and mucosal histamine levels have been measured after storage and reperfusion of Lewis rat small bowel transplants which have received an intravascular flush of saline or of one of the tissue preservation media, hypertonic citrate or University of Wisconsin solution. Plasma histamine concentration was unchanged from a control value of 23.2 +/- 2.6 ng/ml 15 min after reperfusion of grafts, whether fresh or stored for 24 h or for 48 h. Mucosal histamine levels in the grafts fell, however, from a control value of 371.0 +/- 22.9 ng/g tissue, first on storage then further after 15 min reperfusion. No differences were found in these parameters of histamine release between any of the preservation media. It is suggested that histamine may play a role in storage and reperfusion damage to small bowel transplants.