Kinematic analysis of penile reflexes in a rat model of spinal cord injury.
The ex-copula penile dorsiflexion reflex (PDFR) is an established measure of sexual dysfunction in male rat models of spinal cord injury. Although the PDFR after complete spinal transection is well described, information regarding the more clinically relevant incomplete spinal contusion injury model is limited. This study examined, using two-dimensional (2D) kinematic analysis, the relationship between the PDFR and degree of white matter sparing (WMS). Male Wistar rats received a T9 contusion with varying degrees of impactor forces. Weekly kinematic recordings of the PDFR were made 3-8 weeks postinjury. Sexual reflex components examined included maximum angle of penile dorsiflexion, total penile event duration, and penile ascent speed. Post hoc comparison between animals grouped based upon injury severity (moderate-severe: 13.33%-17.15% WMS vs moderate: 20.85%-33.50% WMS) indicated PDFR effects. Specifically, the numbers of animals with more moderate contusions having data points above the median in both maximum angle of penile dorsiflexion and penile ascent speed were significantly lower than animals with more severe injuries. Total penile event duration was also affected but only at more chronic time points (6-8 weeks). Thus, 2D kinematic analysis of the PDFR allows for more consistent and quantifiable analysis of the subtle differences that can occur between injury severity groups in the rat contusion model.
['Steadman|Casey J|CJ|', 'Vangoor|Sai S|SS|', 'Hubscher|Charles H|CH|']
D000818:Animals D001696:Biomechanical Phenomena D004195:Disease Models, Animal D007172:Erectile Dysfunction D008297:Male D010410:Penile Erection D010413:Penis D051381:Rats D017208:Rats, Wistar D012018:Reflex D013119:Spinal Cord Injuries
penile spinal cord injury sexual dysfunction erection