UROGENITAL Flashcards
What does the upper urinary tract consist of?
Kidneys
Ureters
What does the lower urinary tract consist of?
Bladder
Urinary sphincter
Urethra
Prostate (in men)
What is mictruition?
urination
What are the two phases of mictruition?
Storage/continene phase
Voiding phase
What controls continence?
Continence centres in the brain
What does storage of urine require the bladder to do?
Relaxation of the detrusor muscle and simultaneous contraction of the internal and external urethral sphincters.
What nervous system are the bladder and IUS under the control of?
The sympathetic nervous system
What is the sympathetic pathway to stimulate urinary storage?
Impulses travel from the cerebral cortex to the pons (pontine continence centre)–> Sympathetic nuclei in spinal cord–> detrusor muscle + internal urethral sphincter. (travel from spinal cord via hypogastric nerve T10-L2)
At how many ml does the bladder wall signal the need to void?
400ml
Under what nervous control is mictruition?
Parasympathetic
How does the bladder signal that it is time to void?
The cells sense increased pressure, and send afferent signals up through the spinal cord to the pontine micturition centre and cerebrum.
What triggers voiding?
Voluntary decision to urinate causes neurones of the pontine mictruition centre to fire, exciting the sacral ganglionic neurones and causing stimulation of the pelvic nerve (S2-4), causing the detrusor muscle to contract.
What happens to the urethral sphincters during urination?
Pontine micturition centre inhibits Onuf’s nucleus, reducing sympathetic stimulation to the IUS causing it to relax.
Conscious reduction in voluntary contraction of the EUS allows for distention and the passing of urine.
Overview of voiding?
Parasympathetic nervous system send cholinergic (ACh) signals to cause contractio of the detrusor muscle.
Which spinal nerves are involved in voiding?
S3,S4,S5
Overview of storage?
Sympathetic nervous system sends noradrenergic (noradrenaline) signals, causing urethral contraction and detrusor muscle relaxation.
Which spinal nerves are involved in urine storage?
T10, L1, L2
What is the epithelium of the bladder and what is special about it?
Urothelium:
3-7 cells thick and highly specialised so that it is completely impermeable
What is receptive relaxation?
The ability of the bladder’s pressure to remain low despite increasing volume
What is the guarding reflex?
Voluntary control of micturition
What is the action of the testes?
Site of sperm production and hormone synthesis
What is the action of the epididymis?
Stores sperm
Where are the testes located?
Within the scortum
Where is the epididymis located?
Posterolateral aspect of each testicles