Fig. 2

Histopathology and immunohistochemistry of overactive bladder in BOO 6 W, BOO 8 W, and sham groups of female rat animal model. Upper horizontal column in the panel: Hematoxylin and eosin (H&E) staining of OAB and sham control of female rat urinary bladder (ABCDD’): Representative sections of urinary bladder from OAB at 6 & 8 weeks (A, B, C), and control (D,D’), the urothelium, muscle bundles in muscle layer are well arranged and condensed with few interlacing collagens, contrary to bladder wall of OAB where the urothelium is less in thickness, muscle bundles are separated with condensation of collagen. Scale bar = 50 μm. Middle horizontal column in the panel: Masson’s trichrome staining for OAB (A^’B’C’D’) and control (EE’) of female rat urinary bladder, respectively, stained slides in this column are representative of the tissues stained with H&E in the upper column. Urinary bladder smooth muscle cells were stained red and collagen fibers were stained blue. Collages were density interlacing the muscle bundles in OAB group, the control group showed normal distribution of collagen in between muscle bundles. Scale bar = 50 μm. Lower horizontal column in the panel: Immunohistochemical staining of OAB and sham control (FGHI): Distribution of c-Kit-immunoreactive interstitial cells in detrusor smooth muscle. C-Kit positive immunoreactive cells are detected along the muscle bundles and smooth muscle cells surrounding the detrusor muscle layers. In overactive bladders, immunoreactivity against c-kit was highly expressed in OAB after 6 & 8 weeks of BOO (G, F- small red arrows) compared with control where it was not or seldom detected (H, I- small red arrow). Scale bar = 50 μm