[The physiology of penile erection. I. Hemodynamics of penile erection]

Arterial and venous flow and pressure studies of the corpora cavernosa were performed to elucidate the hemodynamics of canine penile erection. Being able to induce erection by electrical stimulation we were able to study the functionally relevant parameters at different stages of penile erection. From our results we conclude that penile erection can be subdivided in 5 phases: (1) latent-, (2) tumescence-, (3) erection-, (4) rigidity- and (5) detumescence phase. Furthermore, a differentiation of these subdivisions is made by observing at the mechanism of the 5 different stages: phase 1 to 4 is an active phenomenon, the detumescence phase is passive only.