Neurogenic impotence is a clinical situation commonly resulting from major pelvic surgery. A detailed description of the neural pathways mediating erection has been lacking and this has been implicated as a major cause for the high incidence of post-operative impotence. Nitric oxide (NO) is a gaseous molecule believed to be an important mediator of erection. The synthesis of nitric oxide is regulated by the enzyme nitric oxide synthase. / In the first part of this work, we studied the neuroanatomical pathways responsible for erection in the male lower urogenital tract. Using a histochemical staining technique able to localize a co-factor of nitric oxide synthase, NADPH, we traced the course of the cavernous nerve and its microscopic branch fibers from the pelvic plexus distally until the penile crura. Studies in a rat model and in man demonstrated multiple small nitric oxide releasing nerve fibers located on the anterior and lateral surfaces of the prostatic capsule. The physiologic importance of these fibers was shown in a rat model. Transection of these fibers resulted in a significant loss of intracavernosal pressure rise following cavernous nerve stimulation. / The nitric oxide synthase enzyme is found in three isoforms: neuronal, endothelial, and inducible forms. The neuronal form is believed to be important in the neural regulation of erection as has been demonstrated in histological studies. Using a specific inhibitor of the neuronal form of nitric oxide synthase, 7-nitroindazole, we evaluated and showed the importance of the neuronal form in regulating erection in an animal model.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.23300 |
| Date | January 1995 |
| Creators | Spiess, Philippe E. (Philippe Edouard) |
| Contributors | Dion, Stephane B. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Division of Surgical Research.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001467516, proquestno: MM08054, Theses scanned by UMI/ProQuest. |
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