Neurology 3 Flashcards
why do we need to know about neurotransmitters?
common
what happens when a nerve transmits its signal down an axon ?
what do we find across the membrane of cells ?
transmembrane potential
what does the membrane consist of?
phospholipid bilayer - impermeable to water
pumps - pumps charged ions out of cell or into
channels - most of the time are closed but can open when they’re supposed to
what will all cells have along their membrane ?
pumps that will pump Na out of cell and K into cell
- so there’s a net positive charge outside the cell and net negative charge inside the cell
- so if we stick an electrode into cell we can record a transmembrane potential
when do the channels in a cell open ?
we there’s a change in voltage around them
what is the resting membrane potential ?
change in potential - this allows signals to pass along cell very quickly
how do we integrate nerve signal?
neurotransmitters which are released from its presynaptic terminal
list the different types of synapses
what are neurotransmitters?
give an eg of a neuromuscular junction
what does the sympathetic system promote?
fight or flight, high bp, increase heart rate
diverts blood from gut to brain and heart and kidneys
what is the principle NT used in sympathetic nervous system ?
noradrenaline - this is why when we use LA with this NT pt feels palpitations
what are sympathomimetics?
drugs that mimic action of SNS
give eg of direct sympathomimetics?
what do we use phenylephrine for?
nasal decongestants
what do we use albutamol for ?
bronchodilator
list some adrenoceptor antagonists ?
what is propranolol?
beta blocker used for anxiety and high BP
what is tamsulosin used for?
prostatic hyperplasia - men that have prostatism
list some indirect sympathomimetics?
what is amphetamine used for ?
stimulates NE which increases BP, HR, excerise and muscle tone
what does cocaine do?
inhibits NE uptake at synapse and hangs around longer which increases HR BP
where else can NT be found other than peripheral nervous system ?
CNS