Effect of putrescine on tissue transglutaminase activity in wounds: decreased breaking strength and increased matrix fucoprotein solubility.

Topical application of putrescine, a transglutaminase inhibitor, for 3 days directly to rat skin wounds produced a significant average decrease of 48 percent in wound breaking strength in test animals from 8 pairs studied between day 5 and day 10 after wounding. No external or systemic toxic effects of putrescine were seen with localized topical application of 50 mM putrescine for 3 days in any of the test rats (n = 12), and no systemic toxicity was seen in rabbits (n = 4) after topical exposure to 50 mM putrescine for 3 weeks. Quantitation of tritiated fucose incorporation in rat wound explants from 10 pairs of rats revealed that a significant overall decrease in radiolabeled glycoprotein production of 23 percent occurred when putrescine was present; in addition, the fraction of tritiated glycoprotein which was soluble in buffer was significantly increased, while that in the buffer-insoluble fraction decreased. This study suggests that putrescine inhibits tissue transglutaminase-mediated cross-linking of fucoprotein in the extracellular wound matrix and supports a role for this process in the generation of incisional wound strength.