Effects of Interferon Gamma on Collagen Expression in the Partially Obstructed Urinary Bladder of Rat / 대한비뇨기과학회지

ABSTRACT

PURPOSE: Recent studies have proved that bladder compliance is closely related to the collagen content of the bladder. It has been shown through human fibroblast, condrocyte, and rat myofibroblasts that interferon(IFN)-gammadecreased collagen synthesis. The objective of this study was to investigate the alteration of collagen deposition and gene expressions in collagen types I and III by partial bladder outlet obstruction and to compare the changes during IFN-gamma treatment. MATERIALS AND METHODS: Following 4 weeks of partial bladder outlet obstruction in 200-250gm. SD rats, the bladder tissues were evaluated for collagen deposition by an immunohistochemical staining using the polyclonal antibodies and the messenger ribonucleic acid(mRNA) contents of the collagen type I and III were evaluated by Northern hybridization. Recombinant IFN-gamma(100,000 units) was administered once a day for 4 weeks by subcutaneous injection. RESULTS: In the control bladders, the immunohistochemical staining for type I and type III collagen protein showed an intense localization in the lamina propria with modest localization in the inter-fascicular region. With obstruction type I and type III collagen staining intensified, especially in the inter-fascicular region. The IFN-gamma administration reduced the inter-fascicular deposition of collagen type I and III. There was an up-regulation of collagen type I and III gene expression after the obstruction. In the obstructed bladders proalpha1(I) and proalpha1(III) collagen mRNA intensity was increased 3.4 and 5.1 folds than the control groups, respectively. This up-regulation was down-regulated by IFN-gamma administration. CONCLUSIONS: The down regulation of collagen types I and III gene expression, and decreased protein deposition after IFN-gamma treatment demonstrated that the effect of IFN-gamma was, in part, transcriptionally regulated. These results suggest that the recombinant IFN-gamma may be beneficial in the treatment of patients with poorly compliant bladder.