Physiology of clitoris
This organ is specially designed for sexual arousal mechanism in the female. It is therefore the most sensitive part of the female sexual nervous system (but there are exceptions). Also, the glans clitoridis is the most sensitive part of the clitoris. It is removed in minimal female circumcision. In maximal female circumcision, the whole of the labia majora are removed along with the clitoris. It is also responsible for the maximal stimulation of sexual activity as in climax or orgasm. Again there are exceptions. This kind of orgasm is said to be different from the vaginal orgasm and is therefore called clitoral orgasm. Vaginal orgasm is not very common and may be present in less than 35% of women but clitoral orgasm is commoner probably because of masturbative activity of women in their earlier ages or easy manipulation by the male partner. Vaginal orgasm is due to deep pressure stimulation of the uterovaginal plexuses of nerves placed in the walls of the vagina. Clitoral orgasm may result from the excitation of these plexuses via tactile stimulation of the organ. It is a copiously innervated organ for its size.
The peripheral function of erection has been studied recently and it involves the release of neurotransmitters from endothelial cells of the clitoris which then relaxes smooth muscle in the arteries, arterioles and erectile tissue trabeculae (corpora cavernosa and corpus spongiosum) of the clitoris and which helps to fill up the erectile tissue with blood and also the sinusoids with expansion of erectile tissues. The venous plexus which drains the clitoris then becomes compressed by these events leading to almost complete blockage of venous outflow from the clitoris. cGMP is the second messenger in this pathway for the action of the principal neurotransmitter of the clitoral erectile action -nitric oxide. cGMP action is terminated by the isoenzyme phosophodiesterase type 5 (PDE5).
School of Medicine
Creator: Oluwole Ogunranti