autonomic pharmacology 2 Flashcards
steps of cholinergic transmission
. Uptake of choline via transporter
2. Synthesis of ACh and AcCOA
3. ACh stored within a vesicle
4. Depolarisation of terminal by action potential
5. Ca2+ influx through voltage activated Ca2+ channels
6. Ca2+ induces exocytosis of ACh
7. Activation of ACh receptors, cellular response
8. Degradation of ACh to choline and acetate by AChE- terminates tramission
9. Reuptake and use of choline
what is Ach synthesised by
acetyltransferase
what is acetyl co a synthesised by
mitochondria
what do nicotinic ach receptors consist of
five glycoprotein subunits that form a central cation conducting na+, k+, ca2+ channel
what do nicotinic acetylcholine receptors exist as
numerous subtypes that are structurally,functionally and pharmacologically distinct
what are the 2 well chategorized subtypes in peripheral ns
skeletal muscle and ganglionic
chategorized subtypes in cns
a4b2 a7
what are all ganglionic transmission blocked by
hexamethonium
amitriptyline
antagonist at histamine h1 receptor and ach m1-m5
noradrengeric transmission at sympathetic neuroeffector junctions
- NA synthesis and storage
- Depolarisation by action potential
- Ca2+ influx through voltage activated Ca2+ channels
- Ca2+ induces release of NA
- activation of adrenoreceptors causing cellular response
- Reuptake and metabolism of NA
- Metabolism of NA by MAO and COMT
drugs acting on b1
pindolol, oxprenolol
drugs acting on b2
salbutamol, salmeterol
what mediates negative feedback inhibition of transmitter release
presynpatic autoreceptors
agonists and antagonsits on negative feedback inhibtion
agonists decrease release, antagonists increase release
atenolol
selective compeititve antagonist of b1
