Loyola University Chicago, Maywood, IL, USA.
Restor Neurol Neurosci. 2009;27(6):633-44. doi: 10.3233/RNN-2009-0489.
The neurotherapeutic effects of nerve electrical stimulation and gonadal steroids have independently been demonstrated. The purpose of this study was to investigate the therapeutic potential of a combinatorial treatment strategy of electrical stimulation and gonadal steroids on peripheral nerve regeneration.
Following a facial nerve crush axotomy in gonadectomized adult male rats, testosterone propionate (TP), dihydrotestosterone (DHT), or estradiol (E(2)) was systemically administered with/without daily electrical stimulation of the proximal nerve stump. Facial nerve outgrowth was assessed at 4 and 7 days post-axotomy using radioactive labeling.
Administration of electrical stimulation alone reduced the estimated delay in sprout formation but failed to accelerate the overall regeneration rate. Conversely, TP treatment alone accelerated the regeneration rate by approximately 10% but had no effect on the sprouting delay. Combining TP with electrical stimulation, however, maintained the enhanced rate and reduced the sprouting delay. DHT treatment alone failed to alter the regeneration rate but combining it with electrical stimulation increased the rate by 10%. E(2) treatment alone increased the regeneration rate by approximately 5% but with electrical stimulation, there was no additional effect.
Electrical stimulation and gonadal steroids differentially enhanced regenerative properties. TP, an aromatizable androgen, augmented regeneration most, suggesting a synergism between androgenic and estrogenic effects. Therapeutically, combining electrical stimulation with gonadal steroids may boost regenerative properties more than the use of either treatment alone.
神经电刺激和性腺类固醇的神经治疗作用已被独立证实。本研究的目的是研究电刺激和性腺类固醇联合治疗策略对外周神经再生的治疗潜力。
在去势成年雄性大鼠面神经挤压切断后，给予丙酸睾酮（TP）、二氢睾酮（DHT）或雌二醇（E（2））全身治疗，并结合/不结合每日近端神经残端电刺激。面神经再生在轴突切断后 4 天和 7 天通过放射性标记进行评估。
单独给予电刺激可减少芽形成的估计延迟，但未能加速整体再生速度。相反，单独给予 TP 治疗可使再生速度提高约 10%，但对发芽延迟无影响。然而，将 TP 与电刺激结合使用可维持增强的速度并减少发芽延迟。单独给予 DHT 治疗不能改变再生速度，但与电刺激结合使用可使速度提高 10%。单独给予 E（2）治疗可使再生速度提高约 5%，但与电刺激结合使用则无额外效果。
电刺激和性腺类固醇可不同程度地增强再生特性。TP，一种可芳香化的雄激素，增强再生作用最大，表明雄激素和雌激素作用之间存在协同作用。在治疗上，将电刺激与性腺类固醇结合使用可能比单独使用任何一种治疗方法更能增强再生特性。
