AB143. Characteristic of platelet-rich plasma and its effects on improving neurogenic erectile dysfunction

Platelet-rich plasma (PRP) containing autologous thrombocyte growth factors is applied in regenerative medicine, but the lack of an optimized PRP preparation protocol causes unstable therapeutic effects. The aim of this study was to optimize the PRP preparation method to obtain the largest amount of growth factors released and compare the effects of PRP from different preparation methods in restoring of erectile function in bilateral cavernous nerve (CN) injury rat model. The in vivo experiments used Sprague-Dawley male rats (n=24) which were randomly divided into four groups of equal numbers: (I) sham operation; (II) vehicle only (which underwent bilateral nerve crushing without treatment); (III) general PRP; and (IV) optimized PRP containing the largest amount of platelet-derived growth factor (PDGF)-AB (groups 3 and 4 underwent bilateral CN crushing with an immediate injection of the respective PRP into the corpus cavernosum). The intracavernous pressure (ICP) of all rats was monitored. Results demonstrated that in the PRP group prepared with the anticoagulant, ACD-A, the amount of PDGF-AB released was statistically higher than those of the other groups (P<0.05). Greater concentrations of PDGF-AB were measured in PRP after chitosan treatment compared to treatment with a solvent or other activating factors. Additionally, storing PRP at –20 °C resulted in a significant increase in PDGF-AB released compared to storage at other temperatures. The optimized PRP prepared by stimulation with chitosan and incubated at –20 °C for 15 days had the largest amount of PDGF-AB and showed a synergistic effect on release (P<0.05). The functional outcome measurement revealed improvement after bilateral CN injury occurred in the group treated with optimized PRP. It was concluded that optimized PRP with a high level of growth factors was more stable, and its injection into the corpus cavernosum facilitated recovery of erectile function.