Penile Vasculature

Origin

The term combines the Latin penis with vasculatura, referring to the system of vessels. Its anatomical and physiological understanding has been critical in urology and male reproductive endocrinology for centuries. Modern understanding emphasizes the dependence of vascular function on nitric oxide signaling and systemic endothelial health.

Mechanism

Erection is a neurovascular event requiring the relaxation of the smooth muscle within the cavernous arteries and the sinusoidal spaces. This relaxation is primarily mediated by the release of nitric oxide (NO) from parasympathetic nerves and endothelial cells, which activates the cGMP second messenger pathway. This leads to massive blood inflow and simultaneous compression of the subtunical venules against the tunica albuginea, trapping the blood and maintaining rigidity.