LC 2.14 Flashcards
what are the 4 phases of sexual response
- desire
- arousal
- orgasm
- resolution
what is the physiology of sexual desire?
- input through sensation and thought
- there is the CNS modulation
- hypothalamus will stimulate testosterone, dopamine, oxytocin and inhibit serotonin
- there are output through the anterolateral columns of the spinal cord
what cause decrease in desire?
- underlying psychological disturbances
- relationship issue
- endocrine
- drugs
what are disorders of desire?
increase desire and decrease in desire
what is the sequence of erection?
1) release of NO
2) relaxation of cavernosal smooth muscle
3) dilation of pudendal arteries
4) increase BP in corpora
5) expansion limited by tunica
6) BP increased to systolic levels
7) rigid erection
what causes the penile erection?
- dilation and engorgement of sinusoids of corpora cavernosa
causes of erectile dysfunction?
- ageing
- psychological
- neurological
- endocrine
- Iatrogenic
what are the features of psychogenic ED?
- sudden onset
- intermittent
- still get morning erections
- poor sexual experiences
- related to relationship issues
- more common in men with psychological problems
what causes vasculogenic ED?
- atherosclerosis in the penile arteries
what does ED predict IHD?
- this is because the penile arteries are more narrow compared to the coronary arteries so easier for blockage
what causes neurogenic ED?
- autonomic neuropathy
- diffuse neurological disease
- CNS disease
- nerve injury though spinal cord, pelvic nerve injury or prostate surger can cause damage to cavernous nerves
what are the endocrine causes of ED?
- low testosterone
- hyperprolactinaemia
- diabetes
managing ED?
- screen for associated disease
- psycological treatment where indicated
- lifestyle factors
- pharmacotherapy
- vacuum erection device
- penile implant
which pharmacotherapy are used?
- centrally acting would be apomorphine and melanocortin agonists
- smooth muscle relaxants such as phosphodiesterase 5 inhibitors
contraindications of phosphodiesterase 5 inhibitors
- nitrate medication - severe cardiac disease
physiology of male orgasm?
- sensory inputs through the pudendal nerve
- there is CNS modulation of the pleasure centres
- motor outputs that will coincides with ejactulation
disorders of orgasm?
- delayed or absent
- painful orgasm
physiology of ejactulation?
- CNS permissive effect
- sympathetic activity through lumbar segments
- noradrenergic response of the alpha receptor
- closure of pre-prostatic sphincter
- opening of the urethral sphincter
- contraction of pelvic floow and muscles
- contraction of seminal vesicles and ejaculatory ducts
- ejaculation
disorders of ejaculation?
- too fast - premature ejaculation
- too slow - delayed ejaculation
- absent - aspermia, retrograde ejaculation, anejaculation
what causes retrograde ejaculation?
- failure of the pre-prostatic sphincter
causes of ejaculatory dysfunction
- psychological
- drugs
- neurological
- anatomical
what happens during male resolution?
- it is called detumescence
- turning off of relaxant mechanisms
- re-establishment of vascular smooth muscle tone
- increase in outflow of the corpora
- decrease in the inflow of the corpora
- maintenance of adrenergic smooth muscle tone
types of priapism
- low flow which is more common and painful
- high flow less common and not painful
what is low flow priapism
- venous blood in the corpora
- increased viscosity of the blood
what is high flow priapism
- arterial blood in the corpora
- arterio-venous malformations
