Wk 25 Flashcards
The bladder receives afferent (sensory) and efferent (motor) innervation via what 2 nerves?
Hypogastric and pelvic splanchnic nerves
Changes in ____ nerves in the bladder wall, structural changes in the _____ or ____ _____ muscles can lead to incontinence
Sensory
Sphincters or pelvic floor
What is the bladder wall mostly made up of?
Smooth muscle
What do the sympathetic neurons do to the bladder?
- Relaxation of detrusor
- Contraction of internal sphincter
Neurotransmitters that control bladder smooth muscle…
What receptors does Acetylcholine act on?
What receptors does Noradrenalin act on?
The external sphincter is closed by ___ acting on what receptors?
Ach= excitatory muscarinic
NA= excitatory alpha or inhibitory beta adrenoceptors
External sphincter closed by Ach acting on nicotinic receptors
When the bladder fills, there is an increase in sensory impulses to what part of the brain?
Pontine micturition centre (Barrington’s nucleus)
What stops adults urinating when their bladder is full?
What allows adults to urinate?
Sympathetic control (tells detrusor muscle to relax and tells internal sphincter to stay closed)
Parasymp (tells detrusor muscle to contract and internal sphincter to open)
- And then somatic control allows adults to open/ close external sphincter when they are ready
Which has a thicker wall, Gram + bacteria or Gram - bacteria?
What colour does gram + stain and what colour does gram - stain?
Gram + have the thick peptidoglycan wall
Gram + stains purple and gram - stains pink (because they have thin cell wall)
What is penicillin binding protein (PBP) involved in?
It is a transpeptidase which cross links peptide chains to build the peptidoglycan cell wall
What does transpeptidase do in bacteria?
What does glycosyltransferase do in bacteria?
Links amino acids for peptidoglycan wall
(B-Lactams block it)
Links sugars for peptidoglycan wall
(Vancomycin)
B-Lactams…
What do they do?
Are they bactericidal or bacteristatic?
Block bacterial cell wall synthesis by blocking transpeptidase
Bactericidal
What are the 4 classes of B-lactams?
Penicillins
Cephalosporins
Monobactams
Carbapenems
What bond do B-Lactams form with PBP and what effect does this have?
Covalent bonds
Inhibiting PBP transpeptidase = weakens cell wall
= bacterial cell lysis and death
Spectrum of action for B-Lactams…
Out of hydrophilic penicillins and hydrophobic penicillins, which is broad spectrum (and why) and which is narrow spectrum?
Hydrophilic is broad spectrum because it can get through the cell wall and cell membrane (gram -) better
Hydrophobic is narrow
What is another inhibitor of cell wall synthesis (that isn’t B-Lactam)
How does it work?
Vancomycin (glycopeptide)
Inhibits release of AA/ sugar building blocks of peptidoglycan cell wall by glycosyltransferase
Reduced number of building blocks= reduced cell wall synth