OBJECTIVETo establish a rat model mimicking erectile dysfunction following radical prostatectomy by crush injury or reaction of the cavernous nerve (CN).

METHODSThirty rats were randomized into CN crush group, CN resection group and sham-operated group. Four weeks after surgery, the rat models were evaluated by apomorphine test and ICP/MAP measurement. Fluorogold (FG) retrograde tracer was used to assess the CN injury. The penile tissues were then harvested for immunohistochemical detection of the nNOS-positive fibers to evaluate the CN injury.

RESULTSThe rats in CN crush group and CN resection group exhibited erectile dysfunction in apomorphine test or in response to electrical stimulation of the ganglion stellatum (MPG). In the sham-operated group, the rats showed normal erectile function with increased ICP/MAP following electrical stimulation (P<0.05). Immunohistochemistry revealed reduced nNOS-positive fibers in both CN crush group and CN resection group as compared with those in the sham-operated group (P<0.05), showing no significant difference between the former two groups (P>0.05). The FG-positive MPG cells in CN crush group and CN resection group were significantly less than that in the sham-operated group (P<0.05), and the positive cells were even less in CN resection group (P<0.05).

CONCLUSIONThe rat CN is structurally similar to human CN, and crush injury and resection of the CN are both reliable methods for establishing rat models of erectile dysfunction following radical prostatectomy.