Home  |   Archive  |   Online Submission  |   News & Events  |   Subscribe  |   APFA  |   Society  |   Contact Us  |   中文版

Ahead of print
Authors' Accepted
Current Issue
Special Issues
Browse by Category

Manuscript Submission

Online Submission
Online Review
Instruction for Authors
Instruction for Reviewers
English Corner new!

About AJA

About AJA
Editorial Board
Contact Us

Resources & Services

Email alert

Download area

Copyright licence
EndNote style file
Manuscript word template
Guidance for AJA figures
    preparation (in English)

Guidance for AJA figures
    preparation (in Chinese)

Proof-reading for the

AJA Club (in English)
AJA Club (in Chinese)


Volume 2, Issue 1 (March 2000) 2, 51–56;

Physiological significance of nitrergic transmission in human penile erection

P.G. Adaikan, S.C. Ng

Department of Obstetrics & Gynaecology, National University Hospital,National University of Singapore, Lower Kent Ridge Road, Singapore 119 074

Advance online publication 1 March 2000


The corpora cavernosa (CC) muscles of the human penis and their structural arrangements are essential for the physiology of erection. Contraction of this muscle causes detumescence, and relaxation, tumescence. The motor excitatory neurotransmission is adrenergic, acting through the alpha adrenoceptors. Continuous adrenergic transmitter (noradrenaline) release is necessary for the maintenance of non-erectile (contractile) state of the penis. The inhibitory neurotransmitter that relaxes CC muscle to produce erection is nitrergic i.e., the chemical messenger being nitric oxide (NO). The latter can also be released from cavernous endothelium. Presence of NO increases intracellular cGMP through activation of the enzyme guanylate cyclase. This causes relaxation of CC muscle. Phosphodiesterase type 5 (PDE5) is responsible for the degradation of cGMP and regulation of CC muscle tone. Specific PDE inhibitors such as sildenafil enhance the intracellular cGMP to improve erection. Increase in intracellular cAMP can also bring about pharmacological erection in man (eg. PGE1, papaverine and histamine). Inhibition of excessive adrenergic tone with appropriate alpha-adrenergic blocking agents (eg. phentolamine) can also contribute to the onset of pharmacological erection.

Full Text |

Browse:  2049
Copyright 1999-2017  Shanghai Materia Medica, Shanghai Jiao Tong University.  All rights reserved