Levels of nitric oxide metabolites do not increase during penile erection.
Cavernosal smooth muscle relaxation, one of the primary events in penile erection, is initiated by the synthesis and release of nitric oxide (NO) from the neurons of the cavernosa. The present study was undertaken to determine whether or not serum levels of NO metabolites rise during an erection. Since NO is rapidly converted into nitrites and nitrates, we measured these serum levels in the peripheral and cavernosal blood of 15 potent adult male volunteers who were exposed to erotic stimuli in order to elicit a penile erection. Our data demonstrate that both nitrite and nitrate levels in the peripheral and cavernosal blood do not appreciably change during and immediately following an erection. This indicates that the determination of whether or not abnormalities in the synthesis and release of NO play any role in erectile dysfunction will require alternative testing methods.
Moriel
E Z
EZ
Department of Surgery, UCLA School of Medicine, Torrance.
Gonzalez-Cadavid
N
N
Ignarro
L J
LJ
Byrns
R
R
Rajfer
J
J
D000328:Adult; D006801:Humans; D008297:Male; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000378:metabolism*; D009573:Nitrites / Q000097:blood; D010410:Penile Erection / Q000502:physiology*
D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide