Presentation Authors: Morgane Flochlay, Nîmes, France, Djibril Diallo, Thomas Bessede, Le Kremlin Bicêtre, France, Evgeny Kharlamov, Oslo, Norway, Vadim Mitrokhin, Moscow, Russian Federation, Michel Prudhomme, Nîmes, France, Boris Aleksandrov, Moscow, Russian Federation, Stéphane Droupy*, Nîmes, France
Introduction: Detailed knwoledge of sensory receptors and nerve pathways of the penis is essential to better understand normal and pathological human sexual response. Few recent works have explored the sensory receptors and some questions remained unanswered regarding the nature of the penile nerves. We aimed to use 3D CAAD to document the presence and topography of sensory receptors and nature, communications and distribution of nerves throughout the human penis.
Methods: Penises were obtained from 2 adult male fresh cadavers of 65 and 78 y.o. Serial transverse sections of 5Î¼m were made and treated with histological and immunohistochemical methods [hematin-eosin (HE) and immunolabelling for protein S100, tyrosine hydroxylase (TH), vesicular acetylcholine transporter (VAChT), neuronal Nitric Oxide Synthase (nNOS), vasoactive intestinal peptide (VIP) and CGRP]. 3D reconstruction of penile structures, vessels, nerves and receptors were obtained from digitised serial sections using WinSurfÂ® software.
Results: Receptors: 2 types of receptors were found: Free Nerves Ending (FNE) and encapsulated Ruffini and Pacini corpuscles.At the level of the glans, FNEs were very numerous and mainly disseminated around the urethral meatus and in the region of the frenulum. Among the encapsulated receptors, Ruffinis' were rare and located underneath the glans surface and foreskin whereas Pacinis' were mainly seen around the erectile corpora and in the penile foreskin.Nerves: The data collected during this study show that at each level: dorsal, cavernous, spongious and ventral, the nature of nerves was mixed: anti and proerectile in various propotions (adrenergic, cholinergic and nitrergic, sometimes VIPergic) and that the sensory fibers are essentially present at level of the dorsal and ventral nerves of the penis. It seemed relevant to differentiate a ventral nerve of the penis from an extension of the perineal nerves because the nerves that we found at the ventral part were symmetrical from the dorsal nerves, smaller but running under the Buck fascia, at the lateral side of the corpus spongiosum to end in the frenulum. Like the dorsal nerves, they were mixed nerves (autonomic and sensitive) receiving fibers from the pudendal nerves and communicating fibers from the pelvic plexus.
Conclusions: Our data clearly demonstrated the mixed autonomic nature of all penile nerves. Sensory penile receptors were mainly FNEs located around the urethral meatus and the frenulum. We identified two ventral nerves of the penis (right and left) containing sensitive, adrenergic, cholinergic, nitrergic and VIPergic fibers, symetrical from the dorsal nerves and ending at the level of the frenulum.
Source of Funding: Rostagroexport ltd. Moscow, Russia.