Drugs & The ANS Flashcards
Give some examples of muscarinic cholinoceptor antagonist drugs & their actions
Tolterodine, darifenacin, oxybutynin:
Treat overactive bladder
Hyoscine:
Anaesthetic premedicati
Ipratroprim bromide:
Tat bronchoconstriction in asthma
Tiotropium:
Treat COPD
homatropine tropicamide:
Pupillary dilation & paralysis
Give some examples of nicotinic cholinoceptor antagonist drugs & their actions
Tubocurarine:
Muscle paralysis during anaesthesia
Give an example of a ganglion-blocking drug & its action
Trimehaphan:
In hypersensitive emergencies
Produce controlled hypotension in surgery
Give some examples of cholinesterase inhibitor drugs & their actions
Edrophonium, physostigimine, dyflos:
Treat glaucoma & myasthenia gravis
Tacrine, donepezil:
Treat alzheimer’s
Give an example of a selective beta 1 agonist drug & its action
Dobutamine:
Negative ionotrophic & negative chronotrophic effects
Give an example of a selective beta 3 agonist drug & its action
Salbutamol:
Bronchodilation - treat asthma
Selectively limits possibly CVS side effects (e.g. Positive ionotrophic/chronotrophic effects)
Give an example of a beta antagonist drug & its action
(Beta blockers)
Propranolol:
Treat hypertension, MI, angina
Unwanted side effects: bronchoconstriction
Additional benefits to treat heart failure (in combination with ACE inhibitor & diuretic)
Give an example of a selective beta 1 antagonisy drug & its action
Atrnolol:
Treat number of CVS disorders, incl Htn
Positive ionotrophic & chronotrophic effects
Mediated through activation of adenylyl cyclase/cAMP signalling pathway
Give some examples of selective alpha 1 agonist drugs & their actions
Phenylephrine:
Nasal decomgestant
Adrenaline:
Local vasoconstriction to reduce dissipation of anaesthetic
Give an example of a selective alpha 2 agonist drug & its action
Clonidine:
Anti-hypertension
Acts on presynaptic receptors to reduce NA release
Give an example of an alpha 1 antagonist drug & its action
Phentolamine:
Treat peripheral vascular disease
Peripheral vasodilation
(Not used to treat Htn as can cause postural Htn)
Give some examples of selective alpha 1 antagonist drugs & their action
Prazosin:
Treat hypertension
Doxazosin
Give some examples of drugs acting at adrenergic nerve terminals & their action
Alpha-methyl tyrosine:
Competitively inhibits tyrosine hydroxylase, blocking synthesis of NA
used in pheochromocytoma
Alpha-methyl DOPA:
Taken up by adrenergic neurones & converted to alpha-methyl-NA
Not a true transmitter; poorly metabolised; accumukates in synaptic vesicles
preferentially activates pre-synaptic alpha2 receptors
Beta-gamma subunit of alpha2 receptor inhibits VOCC, reducing Ca2+ mediated release
CarbiDOPA:
Inhibits DOPA decarboxylase in periphery (not in CNS)
Used in combination with L-DOPA to treat Parkinson’s
Adrenergic blocking drugs:
Selectively concentrated in terminals by Uptake1
Local anaesthetic action; reduce impulse conduction & Ca2+ mediated exocytosis
Repletion of NA from synaptic vesicles
Indirectly acting sympathomimetic agents (IASAs) (e.g. Amphetamine):
Acts like NA, but indirectly
Transported into adrenergic terminal by Uptake1 & into synpatic vesicles
No room for NA in vesicles: leaked into synaptic cleft
NA leakage enhanced by inhibition of MAO enzyme (degrades NA)
Uptake1 inhibitors (e.g. Tricyclic antidepressants):
Central therapeutic action (in CNS)
Peripheral actions my be unwanted side effects (e.g. Tachycardia, dysthythmia)
Give some examples of muscarinic cholinoceptor agonist drugs & their actions
Pilocarpine: Treat glaucoma GI motility post surgery Suppression atrial tachycardia Stimulates bladder emptying
Bethanechol:
Acute treatment to stomulate bladder emptying
