Is there a significance of histamine in the control of the human male sexual response?

Abstract

Although histamine has been suggested to be involved in the control of male sexual function, including the induction of penile erection, its role in the human corpus cavernosum penis is still poorly understood. The aim of our study was to evaluate the course of histamine plasma levels through different stages of sexual arousal in the systemic and cavernous blood of healthy male subjects. Thirty four (34) healthy men were exposed to erotic stimuli to elicit penile erection. Blood was aspirated from the corpus cavernosum and a cubital vein during the penile conditions flaccidity, tumescence, rigidity and detumescence. Blood was also collected in the post-ejaculatory period. Plasma levels of histamine (ng ml(-1)) were determined by means of a radioimmunoassay. Histamine slightly decreased in the cavernous blood when the penis became tumescent. During rigidity, histamine decreased further but remained unaltered in the phase of detumescence and after ejaculation. In the systemic circulation, no alterations were observed with the initiation or termination of penile erection, whereas a significant drop was registered following ejaculation. Results are not in favour of the hypothesis of an excitatory role of histamine in the control of penile erection. Nevertheless, the amine might mediate biological events during the post-ejaculatory period.