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 decre ase of 48 percent in wound breaking strength in test animals from 8 pa irs studied between day 5 and day 10 after wounding. No external or sy stemic toxic effects of putrescine were seen with localized topical ap plication 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 topica l exposure to 50 mM putrescine for 3 weeks. Quantitation of tritiated fucose incorporation in rat wound explants from 10 pairs of rats revea led that a significant overall decrease in radiolabeled glycoprotein p roduction of 23 percent occurred when putrescine was present; in addit ion, the fraction of tritiated glycoprotein which was soluble in buffe r was significantly increased, while that in the buffer-insoluble frac tion decreased. This study suggests that putrescine inhibits tissue tr ansglutaminase-mediated cross-linking of fucoprotein in the extracellu lar wound matrix and supports a role for this process in the generatio n of incisional wound strength.