OBJECTIVETo study angiogenesis and regulatory factors in the proliferated prostatic tissues of Sprague Dawley (SD) rats with BPH induced by testosterone.

METHODSSixteen castrated SD rats, aged 8 weeks and weighing 200 approximately 250 g, were equally randomized into a model group and a control group, and the BPH model was established by subcutaneous injection of testosterone. Immunohistochemistry and MIAS (micro-image analysis system) were used to test the manifestations of MVD (microvessel density), VEGF (vascular endothelium growth factor), flk-1, endostatin, MMP-2 (matrix metalloproteinase-2) and TIMP-2 (tissue inhibitor of metalloproteinase-2) in the prostatic tissues of both the model and the control groups. Multiple linear regression with the stepwise method was adopted to analyze the data.

RESULTSThe manifestations of MVD, VEGF, flk-1, MMP-2, MMP-2/TIMP-2 and VEGF/endostatin in the model group were higher, while that of endostatin was lower than in the control group (P < 0.01), and the manifestation of TIMP-2 showed no statistical difference between the two groups. The regression analysis indicated that MVD was positively correlated to VEGF, VEGF/endostatin and MMP-2/TIMP-2 (r = 0.974, 0.986, 0.982, P < 0.05) and negatively correlated to endostatin (r = - 0.975, P < 0.05) .

CONCLUSIONTestosterone could induce BPH in SD rats by increasing MVD and promoting the multiplication of vascular endothelial cells after regradation of basement membrane.