OBJECTIVE: The goal of this study was to determine whether expression of matrix metalloproteinases (MMP) and tumor necrosis factor-alpha (TNF-alpha) occurs in a gerbil cholesteatoma model, which may be involved early in the pathogenesis of cholesteatoma. Study design Atelectasis was induced by transpalatal, bilateral Eustachian tube obstruction on gerbil ears (n = 60). Tympanic membranes were removed at days 0, 3, 7, 14, 28, 56, and 84, and quantitative analysis of TNF-alpha and MMPs was performed. RESULTS: Atelectasis and middle ear inflammation increased with time. TNF-alpha and MMP levels increased (P < 0.0083) with time, inflammation, and atelectatic stage with some variability seen between different MMPs. CONCLUSION: Elevation of TNF-alpha and MMPs associated with progressive tympanic membrane atelectasis suggests a possible role for these inflammatory mediators in the pathogenesis of cholesteatoma.
OBJECTIVE: The goal of this study was to determine whether expression of matrix metalloproteinases (MMP) and tumor necrosis factor-alpha (TNF-alpha) occurs in a gerbil cholesteatoma model, which may be involved early in the pathogenesis of cholesteatoma. Study design Atelectasis was induced by transpalatal, bilateral Eustachian tube obstruction on gerbil ears (n = 60). Tympanic membranes were removed at days 0, 3, 7, 14, 28, 56, and 84, and quantitative analysis of TNF-alpha and MMPs was performed. RESULTS: Atelectasis and middle ear inflammation increased with time. TNF-alpha and MMP levels increased (P < 0.0083) with time, inflammation, and atelectatic stage with some variability seen between different MMPs. CONCLUSION: Elevation of TNF-alpha and MMPs associated with progressive tympanic membrane atelectasis suggests a possible role for these inflammatory mediators in the pathogenesis of cholesteatoma.