New method for direct stiffness measurement of the corpora cavernosa

We describe a new methodology for direct ex vivo measurements of corporal stiffness. Using a new biosensor, stiffness of the corpora cavernosa was measured in 32 mature male Spraque Dawley rats. Mean stiffness (+/- se) value of the corpora was 8.186 +/- 0.318 gm/cm. The corpora was numerically the stiffest organ, when compared to the bladder and the prostate. Values measured at different points from both corpora showed a quite uniform stiffness (range 7.576-8.835 gm/cm). Hormonal stimulation with DHT was shown to significantly increase prostatic stiffness but not corpora stiffness. Similarly alpha-adrenergic antagonists did not affect corporal stiffness in a statistically significant manner. These results suggest that the influence of hormones and adrenergic stimulation on the passive properties of the corpora is negligible. It is concluded that this new method provides a reproducible new parameter for the measurement of corporal stiffness. It is anticipated that in the future this kind of stiffness measurement may be of use for the evaluation of the biomechanical properties of the corpora and its response to pharmacologic manipulation of the trabecular smooth muscle tone in vivo.