Pharmacology Flashcards
pre-synaptic processes
- choline is transported into the terminal by choline transporter (symport with Na+)
- ACh is synthesised in the cytosol with acetyl coenzyme A by choline acetyltransferase
- ACh is concentrated in vesicles by the vesicular ACh transporter
- when an AP causes depolarisation the Ca2+ enters and causes vesicles in active zones to undergo exocytosis
- ACh diffuses into the synaptic cleft and activates nAChR in endplate region
post-synaptic processes
- two ACh molecules activate each nAChR
- channel equally permeable to Na+ and K+
- when the gate opens, Na+ influxes at a faster rate than K+ effluxes
- causes simultaneous opening of many nAChR
describe the structure of nAChR
pentamers of glycoprotein subunits surrounding central cation pore with a gate that only opens when ACh binds
what terminates ACh?
hydrolysis by acetylcholinesterase
examples of clinical conditions associated with the NMJ
- neuromyotonia
- LEMS
- myasthenia gravis
- botox
- curare
describe neuromyotonia
autoantibodies to K+ channels leading to excitability
management of neuromyotonia
anti-convulsant e.g. carbamazepine
phenytoin (Na+ channels)
three classes of drugs used to treat inflammatory arthritis
- NSAIDs
- DMARDs
- biologics
examples of NSAIDs
ibuprofen
diclofenac
role of NSAIDs
anti-inflammatory
adverse of NSAIDs
GI ulceration
CVS
when should DMARDs be started?
within 3 months
examples of DMARDs
methotrexate
leflunomide
sulfasalazine
hydroxychloroquine
adverse of methotrexate
leukopenia
thrombocytopenia
teratogenic
when is hydroxychloroquine used?
connective tissue diseases
