Penile erection in dogs by magnetic stimulation of the cavernous nerve

The study investigated the effect of magnetic stimulation (MS) of the caver nous nerve on penile erection of the dog. A total of 14 male dogs (mean wei ght 14.8 +/- 3.2 kg) were studied. The cavernous nerve was activated by mea ns of a magnetic coil with a magnetic stimulator, using a stimulation of 70 % intensity, 20 Hz frequency and 50 s on and 50 s off for 10-min duration. With the dog lying supine and anesthetized, the magnetic coil was moved ove r the dorsum of the penis to get the optimal position for obtaining maximal intracorporeal pressure and penile rigidity. This position was found to li e on the penile dorsum in the vicinity of the symphysis pubis. MS with the aforementioned parameters effected an increase of the penile length and dia meter as well as of the intracorporeal pressure (p <.0001). The mean latenc y was 7.8 +/- 2.8 s, and full erection and maximal intracorporeal pressure were achieved after a mean period of 21.4 +/- 5.3 s. Upon off-stimulation, erection and intracorporeal pressure returned to the baseline after a mean of 14.2 +/- 3.2 s. After an off-time of 50 s the response returned and was reproducible indefinitely, provided the off-time period was observed. MS of the cavernous nerve led to full penile erection in the dog. This method is noninvasive, simple, easy, and safe. It can be applied in humans with erec tile dysfunction.