Mice Deficient in Urokinase-Type Plasminogen Activator Have Delayed Healing of Tympanic Membrane Perforations
نویسندگان
چکیده
Mice deficient in plasminogen, the precursor of plasmin, show completely arrested healing of tympanic membrane (TM) perforations, indicating that plasmin plays an essential role in TM healing. The activation of plasminogen to plasmin is performed by two plasminogen activators (PAs), urokinase-type PA (uPA) and tissue-type PA (tPA). To elucidate the functional roles of PAs in the healing of TM perforations, we investigated the phenotypes of single gene-deficient mice lacking uPA (uPA(-/-)) or tPA (tPA(-/-)) after TM perforation. Delayed healing of TM perforations was observed in uPA(-/-) mice but not tPA(-/-) mice. The migration of keratinocytes was clearly delayed and seemed to be misoriented in uPA(-/-) mice. Furthermore, fibrin deposition and the inflammatory response were persistent in these mice. Our findings demonstrate that uPA plays a role in the healing of TM perforations. The observed phenotypes in uPA(-/-) mice are most likely due to the reduced generation of plasmin.
منابع مشابه
The Effects of Plasminogen Deficiency on the Healing of Tympanic Membrane Perforations
The healing of tympanic membrane (TM) perforations is a complex wound healing process including inflammation, migration of keratinocytes and tissue remodelling. Most TM perforations in human heal spontaneously, however some perforations become chronic, and the reason why is still largely unknown. In cutaneous wound healing plasminogen (plg) has been shown to play an important role. Plg is conve...
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