Models for erectile dysfunction and their importance to novel drug discovery.

INTRODUCTION: Erectile dysfunction (ED) affects quality of life and is a barometer for vascular health. The pathophysiology is complex and multifactorial. Animal models have been critical in elucidating an improved comprehension of erectile function. They provide experimental platforms where desired physiologic, and non-physiologic perturbations can be performed. Results have led to the development of novel therapeutic targets. AREAS COVERED: The current article provides an overview of history of animal models in ED research as well as a review of the current roles in the study of ED. The authors highlight the advantages and disadvantages of each model while illustrating the similarities to the human condition and summarizing the major preclinical studies investigating novel therapeutic targets in the treatment of ED. EXPERT OPINION: Animal models have been instrumental in the discovery of the current therapeutic agents. Advances in molecular biology and proteomics have uncovered many novel potential targets including tissue regeneration and stem cell applications. Rodent models are the current animal model of choice for ED research due to lower cost, well-established modeling protocol, and the ability to manipulate genetically. Future clinical trials should directly assess the translatability of these animal models to humans as well as the safety risks and long-term efficacy that the results generate.