Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
61 Cards in this Set
- Front
- Back
|
Which hormones affect sexual desire, arousal, an orgasm
|
– Testosterone (+ initiation of desire)
– Oxytocin (+orgasm) - Prolactin (- arousal) - Progesterone (+ receptivity of desire) - Estrogen (+ permissive effect on desire) |
|
|
Role of testosterone in sexual function
|
Critical for sexual interest and arousal and both men and women
|
|
|
Role of oxytocin in sexual function
|
Has both excitatory and inhibitory effects
|
|
|
Role of prolactin in sexual function
|
Inhibitor factor via direct inhibition of dopaminergic activity
|
|
|
Role of dopamine in sexual function
|
Facilitates libido and has positive effects on genital arousal
|
|
|
Role of noradrenalin in sexual function
|
Complicated effects depending on concentration and set of action
– In the brain, is generally stimulating – In the periphery, causes vasonstriction keeping the erectile tissue detumescenced - necessary to trigger ejaculation |
|
|
Role of Acetylcholine in sexual function
|
– Preliminary role in nitric oxide release and peripheral smooth muscle relaxation in erectile tissue
– Necessary for the pelvic muscle contractions of orgasm |
|
|
Role of serotonin in sexual function
|
Dampens all levels of sexual response in the brain
|
|
|
Which neurotransmitters facilitate sexual interest
|
– Noradrenalin
– Dopamine |
|
|
Which neurotransmitters facilitate genital arousal
|
– Acetylcholine
– dopamine |
|
|
Which neurotransmitters facilitate orgasm
|
– Acetylcholine
– Noradrenalin |
|
|
Noradrenalin has an inhibitory effect on
|
Genital arousal
|
|
|
Serotonin has an inhibitory effect on
|
– Interest
– Genital arousal – Orgasm |
|
|
In order for genital arousal and ejaculation to occur, what needs to be overcome
|
This strong inhibitory tone that exists in nonsexual situations (descending pathway)
|
|
|
Sympathetic nerves responsible for inhibition of erection leave through spinal cord levels
|
T11-L2
|
|
|
Parasympathetic nerves responsible for stimulating erection leave through spinal cord levels
|
S2-S4
|
|
|
Both sympathetic and parasympathetic fibers involved in direction travel through
|
The pelvic plexus and cavernous nerve to the end organs
|
|
|
Touch and rub somatosensory information from pubic and perineal area to spinal cord : pathway
|
– Through dorsal nerve of the penis/clitoris
– Sensory fibers run with motor fibers in pudendal nerve – Travel to sacral 2,3,4 levels |
|
|
Deep pressure and visceroreceptive somatosensory information from pubic and perineal area to spinal cord : pathway
|
– Travel along with the pelvic and hypogastric nerves
– Enter spinal cord via the thoracolumbar roots |
|
|
Sensory afferents for touch, rub, deep pressure and visceroreceptive stimuli terminate where within the spinal cord
|
Mediodorsal horn
Dorsal Gray column |
|
|
Nocturnal penile tumescene
|
- Noradrenergic cells in locus coerulus switched off during sleep
- release of genital arousal inhibition – Reduction in inhibitory tone permits expression of excitatory tone |
|
|
What are the three sets of neuron's in the spinal cord anatomically linked with sexual organs and their function
|
– Thoracolumbar sympathetic (T12-L3)
– Sacral parasympathetic (S2-4) – Somatic (anterolateral column, pudendal nerve |
|
|
From the brain what are the two areas in the cord that provide the main transmission of efferent sexual signals
|
T10-L3
S2-4 |
|
|
T10-L3 segments responsible for
|
Transmission of psychogenic erection in men
– Reliant on the release of cortical inhibition or physical impedement |
|
|
S2-4 segments responsible for
|
Reflex erection
– Responds to somatic stimuli applied to genitalia and delivered via the pudendal n. – Parasympathetic bundles return --> reflex erection – Contraction of ischiocavernosus and bulbospingiosus muscles |
|
|
What is an orgasm
|
The brain's interpretation or cerebral processing of afferent stimuli likely via the pudendal n.
|
|
|
Afferent stimuli leading to orgasm
|
– Smooth muscle contraction of the accessory sex organs
– Build up and release the pressure in the posterior urethra – Sensation of ejaculatory inevitability – Contraction of urethral bulb and perineum |
|
|
Can someone sobbing ejaculation or direction after a spinal cord injury
|
Yes, it is possible to have direction, ejaculation and orgasm as separate events.
– can be a combination of one or two without the other |
|
|
Lumbar spinothalamic cells
|
Interneurons that appeared to orchestrate the coordinated activation of autonomic and somatic spinal centers leading to normal anterograde ejaculation and possibly promote orgasm
|
|
|
What are the two stages of ejaculation
|
- Emission phase
- Expulsion |
|
|
Describe stage one of ejaculation
|
– Called Seminal emission
– Consists of: sperm transport and seminal fluid formation – Vasocongestion of the internal genitalia – Pleasurable feelings of tension –Sym and Parasymp tones act synergistically to initiate seminal emmsion |
|
|
Role of sympathetic and parasympathetic tone on seminal emission
|
– Sympathetic's activate smooth muscle contraction in accessory glands
– Parasympathetic's activate epithelial secretion in accessory glands |
|
|
Ejaculatory inevitability
|
When the seminal bolus enters a prostatic urethra
– Loss of voluntary control |
|
|
Describe stage of ejaculation
|
The actual process of explosion of seminal fluid through intermittent relaxation of the external urinary sphincter
|
|
|
Role of parasympathetic's in expulsion
|
Spasmotic contractions of the seminal vesicles, prostate and urethra propel the seminal bolus distally
– Fibers from S2,3,4 |
|
|
Role of sympathetic's in seminal expulsion
|
Closer of the bladder neck [internal urinary sphincter] prevents retrograde it just relation
– Fibers from L1/2 |
|
|
Somatic role in seminal expulsion
|
– Contractions of bulbospongiosus, ischiocavernosus, lavator ani
- from S2-4 pudendal nerve – Rythmic 0.8 second contractions |
|
|
Post ejaculation refractory period
|
– Experience by men after ejaculation an orgasm
- second ejaculation is not possible during this time – Women do not have a refractory period and have the capacity to be multi-orgasmic |
|
|
5-HT effects on desire, arousal and orgasm
|
- inhibitory effected on arousal and desire indirectly via inhibition of other hormones ( dopamine, NE, T)
|
|
|
Three main hormones involved in maintaining genital structure and function
|
– Estrogen
– Testosterone – Progestin |
|
|
5-HT effects on sensation and vasocongestion
|
Inhibitory: direct and indirect (via NO inhibition)
|
|
|
Effects of cervical injury above T9 on sexual function
|
– No messages can get to psychogenic center
– Become reliant on reflectogenic center for arousal |
|
|
Effects of sacral injury on sexual function
|
– No reflects excitability from touch
– Psychogenic arousal still possible – Become reliant on mental arousal |
|
|
Effects of a lesion between cervical and sacral centers on sexual function
|
Because the centers reinforce each other, these arousals are clinically unreliable
|
|
|
Effective diffuse lesions or progressive diseases (like MS) on sexual function
|
Fibers or damage so take a long time for messages to get through and for the centers to reinforce each other.
|
|
|
Physiology of erection
|
– Parasympathetic nerves release acetylcholine, NANC
– The chick oxide production – Increase cGMP intracellular within smooth muscle – Smooth muscle relaxation – Dilation of blood vessels [rigid outflow erection] - In women, the bulbs and crus will engorge and lubrication occurs |
|
|
Methods of enhancing erections
|
–PDE-5i (Viagra) :prevents cGMP--> GMP so maintains erection for longer
– Intracavernosal injection - MUSE (capsule into urethra) - Constrictor band, vacuum device, pump |
|
|
Causes of ejaculation without orgasm
|
– Spinal cord injury
– MS – Anhedonic ejaculation [neurologically normal people lose feeling of orgasm] |
|
|
Causes of orgasm without ejaculation
|
– Prostate removal
– Retrograde ejaculation – Retroperitoneal lymph node dissection [May injure sympathetic chain and nerves] |
|
|
What can go wrong in ejaculation
|
– Commission and proposing don't work
– A mission failure – Pro pulsatile failure – Retrograde ejaculation – Obstruction |
|
|
In which population is retrograde ejaculation more prevelant
|
Men with long-term diabetes and bladder neuropathy
|
|
|
Describe penile vibrostimulation
|
– Reliant on intact lumbosacral reflex
– Causes high afferent and efferent simulation – Reflex erection – The higher the lesion the less interference with vibrostimulation |
|
|
Describe electroejaculation
|
– Invasive and time-consuming
– Less repeatable – May require anesthesia – Relying on efferent component of reflux |
|
|
Bulbocavernous reflex test
|
– Tap penis or clitoris and contraction of bulbocavernous muscle should result
– Reflective of intact sensory and motor sacral pathway – Predictive for: reflex arousal, ejaculation |
|
|
What does a positive bulbocavernosus reflex test indicate
|
– Positive result confirms sacral reflex is open
|
|
|
Pinprick sensation/temp/voluntary anal contraction test
|
– Differentiation between sharp and dull
– Rectal insertion for test of voluntary contraction of anal sphincter |
|
|
What does a positive result of the pinprick tests indicate
|
Spinothalamic tract intact
|
|
|
What does a positive result of the rectal insertion test indicate
|
Corticospinal tract intact [voluntary anal contraction]
|
|
|
What does a positive testicular squeeze tests indicate
|
If they can feel squeeze, sensory Innervation of T9 to the brain must still be intact therefore injury must be below T9.
|
|
|
What does a positive/negative anal tone tests indicate
|
Indicates that the lumbosacral autonomic's and motor tracts are likely unimpeded
- negative result may explain disordered ejaculation |
|
|
Sexual symptoms of women with MS
|
– Poor lower motor ability
– Saddle numbness – Reduce genital sensation – Dull pinprick, very weak voluntary anal contractions and BCR – Neurogenic bladder and bowel, fatigue, lack of sexual payoff |
