Biochemical Alterations in Partial Bladder Outlet Obstruction in Mice: Up-Regulation of Mitogen Activated Protein Kinase Pathway

Purpose: We evaluated the effect of partial bladder outlet obstruction on bladder weight, protein synthesis, mitotic markers and the mitogen activated protein kinase pathway in a mouse model. Materials and Methods: Mice were divided into 3 groups, including control, sham treated and partially obstructed. Bladders were harvested from the mice in the partially obstructed group 12, 24, 48, 72 and 168 hours after surgical partial outlet obstruction, respectively. Partially obstructed bladders were compared to bladders in the control and sham treated groups by weight, protein content, and expression of proliferating cellular nuclear antigen, cyclin D3, HsP 70, c-jun and phosphorylated c-jun. Bladders were examined histologically for changes occurring with partial obstruction. Results: We tested 3 groups of mice, including control, sham treated and partially obstructed mice, to understand the pathophysiology of the bladder response to partial obstruction. We found no statistical difference in body weight among the groups. Furthermore, there was a significant increase in bladder weight and protein content in partially obstructed mice compared to those in controls and sham operated mice. There was up-regulation of proliferating cellular nuclear antigen, cyclin D3, HsP70, c-jun and phosphorylated c-jun with partial obstruction. Fibrosis was prominent at 168 hours compared to that in controls. Conclusions: Bladder weight and protein content increase with partial bladder outlet obstruction in mice. Cell cycle proteins and elements of the mitogen activated protein kinase pathway are up-regulated during this process.