Bladder and Urinary Tract Lecture Flashcards
Pyeloureteric peristalsis
movement of urine efficiently into the ureter; originates from the renal pelvis where urine produced in the kidney collected
What causes pyeloureteric peristalsis?
initiation by pacemaker cells, which drive rhythmic electrical and mechanical events from the renal pelvis to the ureter.
Main sites where kidney stones get stuck?
- at the ureteric junction of renal pelvis;
as the ureter passes over the iliac vessels; - at the junction of the ureter and the bladder
Blocking urine flow increases pressure in the kidney and can lead to this condition.
hydronephrosis
Where is the main site of pacemaker cells in the kidney?
Renal pelvis
3 critical regions of bladder function
- urothelium
- suburothelium (afferent pathways)
- muscularis (efferent pathways)
Two types of fibers involved in sensory perception
- A-gamma: mechanosensitive neurons
2. C fibers: mechanically insensitive, participate in nociception
3 main mechanisms for regulation of contraction in detrusor muscle cells
- Entry of Ca+
- Release of Ca+ from cellular stores
- Sensitization of contractile apparatus by inhibiting myosin light chain phosphatase
The kidney exhibits this quality, which allows for proper filling.
Enhanced compliance! So, very little pressure build up despite a large increase in volume.
Characterized by a sudden, uncomfortable need to urinate with or without urine leakage. This can occur frequently during both the daytime and nighttime
Overactive bladder
Predominant pharmacological treatment for patients with overactive bladder
Antimuscarinic drugs
The main problem with males and urination
An enlarged prostate (benign prostatic hyperplasia)
What would occur if bladder compliance was decreased?
Increased pressure build up with increasing volume
Occurs when the muscles and tissue that help support the bladder become weak. When there is increased pressure against the bladder and the sphincter does not stay closed, leakage occurs
Stress incontinence
Another word for peeing
micturition
Nerves involved in the filling phase of the bladder
Hypogastric
Pelvic
Pudendal
What happens to the external sphincter during bladder filling?
What about the internal sphincter?
What about detrusor muscle?
What happens to parasympathetic outflow?
Contraction of both sphincters.
Inhibition of detrusor muscle.
Inhibition of parasympathetic outflow.
Antimuscarinic drugs can cause this undesired side effect
Constipation
The parasympathetic PELVIC nerve essentially does three things. What are they?
- ACh binds to M3 receptors and stimulates detrusor muscle
- ATP binds to P2X1
- NO binds to GC to relax urethral smooth muscles
The sympathetic HYPOGASTRIC nerve does two things. What are they?
- NE binds to alpha 1 to cause smooth muscle contraction
2. NE binds to B3 to inhibit bladder detrusor muscle
What does the detrusor muscle do during filling vs. urination?
Relaxes during filling, and contracts during urination.
What do the sphincters do during filling vs. urination?
Contract during filling, relax during urination.
What does the somatic PUDENDAL nerve do?
stimulates the external urethral sphincter, mediated by ACh-activating nicotinic (N) receptors
