Vasoactive peptides CGRP

ANF atrial natriuretic peptide CGRP calcitonin gene-related peptide VIP vasoactive intestinal peptide... 

Erection occurs as a result of increased pressure in the corpora cavernosa, which translates into penile rigidity. The pressure increase is caused by three synergistic processes (i) relaxation of the smooth muscles of the corpora cavernosa (2)increase in arterial blood flow to the penis and (5) restriction of the venous blood flow out of the penis. Both central and peripheral mechanisms contribute to the process of penile erection. At the central level, the psychological component of penile erection is controlled by the hypothalamic and limbic systems (140). At the peripheral level, both sympathetic and parasympathetic pathways as well as several mediators are involved. Psychogenic and local stimulation results in the release of neurotransmitters from the cavemosal nerve terminals and smooth muscle endothelium. Factors that mediate the corpus cavemosum relaxation include nitric oxide (NO), vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP), and prostaglandin. 

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