16 - Neural Anatomy of Erectile Tissue and the Role of the Parasympathetic Nervous System in Erection

Saturday, March 23, 2024

5:00pm – 7:00pm US EDT

Location: Sheraton Hall

Poster Board Number: 16
There are separate poster presentation times for odd and even posters.
Odd poster #s – first hour
Even poster #s – second hour

Co-authors:

Lori Buhlman - Faculty Researcher, Biomedical Sciences, Midwestern University; Monica Castro - Senior Research Specialist, Anatomy, Midwestern University; Justin Georgi - Faculty Researcher, Anatomy, Midwestern University; Margaret Hall - Faculty Researcher, Anatomy, Midwestern University; Nafisa Jadavji - Faculty Researcher, Biomedical Sciences, Midwestern University; Corinne Jedynak-Bell - Physician, Osteopathic Medicine, Midwestern University; Jose Rodriguez-Sosa - Faculty Researcher, Anatomy, Midwestern University; Dominik Valdez - Research Specialist, Anatomy, Midwestern University

Presenting Author(s)

Julio E. Villarmán, MA

Student
Midwestern University
Peoria, Arizona, United States

Abstract Body : Introduction: Stimulation of erectile tissue is currently understood to be facilitated by both sympathetic and parasympathetic nerves. However, the presence or absence of post-ganglionic cell bodies within erectile tissues have yet to be defined in the literature. Clinically, some patients recovering from a penectomy followed by a vaginoplasty can still maintain an erection of the phallic glans. The only known nerve preserved followed by these procedures is the dorsal nerve of the phallus. This nerve, as a ventral ramus, contains both somatic sensory and postganglionic sympathetic axons, but is not understood to include parasympathetic axons. Generally, some sources suggest that the cavernous nerve contains parasympathetic axons destined to the erectile tissues of the phallus, but if this is the case it has not been demonstrated if these axons are preganglionic or postganglionic. Here we hypothesize that if the cavernous nerve contains preganglionic parasympathetic axons, postganglionic cell bodies may be present in the phallus. Materials and Methods: Using standard dissection techniques on 3 male and 3 female human body donors, we collected tissue from the internal urethral sphincter, the bulb of the vestibule, and several control tissues including a paravertebral ganglion for the purpose of comparative morphology. The tissue samples were processed into paraffin wax and prepared tissue samples were mounted on positively charged glass slides at 5 microns. All tissues were stained with H&E and the bulb of the vestibule and the internal urethral sphincter samples were additionally stained with primary monoclonal antibodies and secondary anti-Neun followed by a DAPI-Aqueous mounting medium to visualize neurons. Results: We found all the autonomic nerves presented histologically with standard peripheral nerve morphology. We found no evidence of postganglionic cell bodies within internal sphincter tissue of the bladder or the erectile tissue. These results were compared to a positive control of paravertebral ganglionic tissue samples which have cell-bodies present. Conclusion: Based on these findings it is possible that the erection of the glans may be organized through sympathetic innervation only. We suggest that “parasympathetic” may have been taught as a term to describe any nerves that do not travel the path of the sympathetic chain and that cranial and pelvic parasympathetics may not represent a single system. Key Terms: cavernous nerve, erectile tissues, inferior hypogastric plexus, parasympathetic, sympathetic.