Back to Annual Meeting Program

In Vivo Mouse Model for Evaluation of Synaptic Transmission Following a Cavernous Nerve Injury
Background: Despite technical advances in the surgical treatment of localized prostate cancer, erectile dysfunction remains a frequent complication. Recent studies documented that peripheral nerve damage, due to axotomy, crush and stretch, causes changes beyond severed cavernous nerve fibers. One example involves disrupted synaptic transmission between pre and postganglionic neurons. In this study, an in vivo mouse model was used to evaluate the synaptic neurotransmission in a major pelvic ganglion (MPG).
Methods: C57Bl6 male mice were anesthetized with isoflurane. The cavernous nerve running on the postero-lateral side of the prostate was identified through a lower midline abdominal incision. A short segment of the nerve was dissected from the surrounding tissue. Similarly, a short segment of pelvic nerve was identified adjacent to the MPG. A bipolar silver electrode with hook-shaped poles was positioned under each of the nerves. The nerve-electrode complexes were embedded in the biocompatible silicon adhesive and the abdominal cavity was closed. Subsequently the cavernous body was canulated at the base of the penis. Electrostimulation of cavernous and pelvic nerves was then performed and the responses was compared. Subsequently, we investigated the effect of nerve stretch on pelvic nerve-induced increase in the intracavernous pressure.
Resutls: Using this protocol, the pelvic nerve stimulation-induced increase in the intracavernous pressure was on average 14% lower than the pressure induced by stimulation of the ipsilateral cavernous nerve (N=5). In coparrison to animals with intact cavernous nerves, the pelvic nerve stimulation-induced intracavernous pressure in an animal with the nerve injury was reduced by an average of 48% (N=4).
Conclusions: This study demonstrates that a reproducible increase in the intracavernous pressure could be induced by stimulation of the pelvic nerve. This model could therefore be used for testing antiinflammatory and neurtrophic factors, which were shown to increase the level of recovery of synaptic transmission in other parts of the neural system.