title: Pathophysiology of erectile dysfunction.
abstract: BACKGROUND
  Multiple regulatory systems are involved in normal erectile function. Disruption of psychological, neurological, hormonal, vascular, and cavernosal factors, individually, or in combination, can induced erectile dysfunction (ED). The contribution of neurogenic, vascular, and cavernosal factors was thoroughly reviewed by our committee, while psychological and hormonal factors contributing to ED were evaluated by other committees.
  
  
  OBJECTIVE
  To provide state of the art knowledge on the physiology of ED.
  
  
  METHODS
  An international consultation in collaboration with the major urology and sexual medicine associations assembled over 200 multidisciplinary experts from 60 countries into 17 committees. Committee members established specific objectives and scopes for various male and female sexual medicine topics. The recommendations concerning state-of-the-art knowledge in the respective sexual medicine topic represent the opinion of experts from five different continents developed in a process over a 2-year period. Concerning the pathophysiology of ED committee, there were seven experts from five different countries.
  
  
  METHODS
  Expert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.
  
  
  RESULTS
  The epidemiology and classification of neurogenic ED was reviewed. The evidence for the association between vascular ED and atherosclerosis/hypercholesterolemia, hypertension and diabetes was evaluated. In addition, the pathophysiological mechanisms implicated in vascular ED were defined, including: arterial remodeling, increased vasoconstriction, impaired neurogenic vasodilatation, and impaired endothelium-dependent vasodilatation. The possible mechanisms underlying the association between chronic renal failure and ED were also evaluated as well as the evidence supporting the association of ED with various classes of medications.
  
  
  CONCLUSIONS
  A better understanding of how diseases interfere with the physiological mechanisms that regulate penile erection has been achieved over the last few years, which helps establish a strategy for the prevention and treatment of ED.
authors.affiliation: Fundación para la Investigación y el Desarrollo en Andrología, Madrid, Spain.
authors.forename: Iñigo
authors.initials: I
authors.lastname: Sáenz de Tejada
authors.forename: Javier
authors.initials: J
authors.lastname: Angulo
authors.forename: Selim
authors.initials: S
authors.lastname: Cellek
authors.forename: Nestor
authors.initials: N
authors.lastname: González-Cadavid
authors.forename: Jeremy
authors.initials: J
authors.lastname: Heaton
authors.forename: Robert
authors.initials: R
authors.lastname: Pickard
authors.forename: Ulf
authors.initials: U
authors.lastname: Simonsen
mesh_terms: D002317:Cardiovascular Agents / Q000009:adverse effects; D002318:Cardiovascular Diseases / Q000150:complications / Q000503:physiopathology; D048909:Diabetes Complications / Q000503:physiopathology; D007172:Erectile Dysfunction / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology; D008297:Male; D009422:Nervous System Diseases / Q000150:complications / Q000503:physiopathology; D011619:Psychotropic Drugs / Q000009:adverse effects
chemical_list: D002317:Cardiovascular Agents; D011619:Psychotropic Drugs