[The effect of blocking penile blood drainage on stem cells therapy for rats with erectile dysfunction]

Objective: To investigate the effect of blocking penile blood drainage at the root of the rat penis on cell retention, penile erectile function, and histopathological changes when erectile dysfunction (ED) is treated by intracavernous injection (ICI) of stem cells. Methods: Thirty male SD rats were randomly divided into sham operation group (n=6), ED model group (n=6), treatment group A (blockade group, n=9) and treatment group B (non-blockade group, n=9). Twenty-four hours after the model was established, group A and group B were treated by ICI of 1 × 10(6) adipose-derived stem cells (ADSCs). Before ICI, the penile blood drainage in group A was temporarily blocked with a rubber tourniquet at the root of the penis which was removed 5 minutes after the injection. The dynamic changes of the local fluorescent signal of the penis and the expression of the fluorescent signal in the lung were detected after ICI. The maximum intracavernous pressure/mean arterial pressure (ICPmax/MAP) was measured to evaluatethe erectile function, and histopathological changes of the penis were observed after 28 days. Results: At different time points (0, 10 and 60 min), the intensity of the bioluminescent signal (×10(6)·p·s(-1)·sr·cm(-2)) in group A had a similar trend when compared with that in group B, and the differences were not statistically significant (8.76±1.17 vs 8.16±1.12, 6.45±1.47 vs 6.72±0.69, 3.77±0.30 vs 3.36±1.06, all P>0.05). A large number of ADSCs could be found in the lungs in both treatment groups after 60 min of ICI. There was no statistically significant difference in erectile function (0.44±0.11 vs 0.43±0.07) and histopathological change (0.08±0.02 vs 0.08±0.03) regardless of the occlusion of blood drainage at the root of the penis (all P>0.05). Conclusion: Temporarily blocking of penile blood drainage has no obvious advantage in improving cell retention and efficacy when ADSCs are used to treat ED of rat models.