Role of the NANC innervation and flow-induced relaxation in the internal pudendal artery

• Grant number: 11/23060-3
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2012
• End date: March 31, 2014
• Field of knowledge: Biological Sciences - Pharmacology - Cardiorenal Pharmacology
• Principal Investigator: Rita de Cassia Aleixo Tostes Passaglia
• Grantee: Rita de Cassia Aleixo Tostes Passaglia
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated researchers: Fernando Silva Carneiro

Abstract

In health individuals, penile erection is a complex neurovascular event that relies on the coordinated and almost simultaneous relaxations of the pre-penile arteries and cavernosal smooth muscle. Although a role for the non adrenergic-non cholinergic neurotransmission (NANC) in the cavernosal smooth muscle relaxation is well established, its contribution for the relaxation of pre-penile vessels is less understood. The internal pudendal artery is primarily responsible for the blood supply to the deep structures of the penis and for around 70% of the resistance to the blood flow to the cavernosal tissue. Whereas a dysfunctional IPA may lead to erectile dysfunction (ED), conditions associated with a decreases in the IPA resistance is associated to priapism. Although it is clear that the IPAs are essential to control blood inflow to the penis, the mechanisms that modulate the IPA tonus are almost unexplored. Therefore, the present project aims to determine whether: 1) the IPAs are innervated by NANC fibers; 2) the NANC innervation produces vasodilation; 3)NO is the main mediator of NANC relaxation in the IPA; 4) the IPAs exhibit flow-induced dilation responses. (AU)