ANS Flashcards
What are the locations of M1, M2, M3
M1- ALPHA 1
M2- BETA 1
M3-BETA 2
Where does M1, M2, M3, APLHA 1, BETA 1 AND BETA 2 ACT
M1- STOMACH
M2- HEART
M3 - EXOCRINE GLANDS
ALPHA 1- VESSELS
BETA 1- HEART, JGC, KIDNEYS
BETA 2- BRONCHI, UTERUS
Describe direct acting cholinergic agonists
Examples: ACH, Betanachol, carbachol, pilocarpine
MOA: Mimic ACH by binding directly to cholinoreceptor
PSNS stimulation; miosis, redness, decreases blood pressure
Indications: Urinary retention, Megacolon, Atonic bladder –> Bethanechol
Treatment glaucoma, optic nerve neuropathy d/t increase of intraocular pressure- > pilocarpine
Sjogren syndrome-> Pilocarpine
S/E: DIARRHEA URINATION MIOSIS/MUSCLE WEAKNESS BRONCHORREA EMESIS LACRIMATION SWEATING
INDIRECT ACTING CHOLINERGIC AGONIST: Reversible
Examples: Edrophonium, neostigmine, physostigmine
MOA: ache inhibitors block ash esterase to stop to from cleaving ACH. act then accumulates in the synaptic cleft.
Indications: Dx of myasthenia graves
INDIRECT ACTING CHOLINERGIC AGONIST: Reversible
Examples: Edrophonium, neostigmine, physostigmine
MOA: ache inhibitors block ash esterase to stop to from cleaving ACH. act then accumulates in the synaptic cleft.
Indications: Dx of myasthenia gravis (when antibodies attack the NMJ receptors causing muscle weakness) –> Edrophonium
tx of myasthenia gravis—> Physostigmine
Alzheimers—-> Tacrine, Donezipil, Rivastigmine, Glutamine
Glaucoma—-> Pilocarpine
S/Es: Nausea, Abdominal pain, decrease blood pressure, Redness/ Flushing, Bronchospam) cholinergic stimuLATION
Diarrhea, GI distress
C/I: Peritonitis, IBD
*Atropine is given in a cholinergic crisis
Indirect acting cholinergic agonist: Irreversible
Example: Ecothiophate (Short Acting)
MOA: Covalently binds to ACHe–> Longer half life–> choline
Indications: Glaucome (Not 1st line)
Long DOA–> 3 weeks
Side Effects: Nausea, abdominal pain, decrease in BP, Redness/ flushing, diarrhoea, GI DISTRESS*
AntiMuscarinic / Cholinergic Antagonist
MOA: Blocks cholinorecptors—> Antimuscarinic effect
Indications: Cholinergic Reactions Parkinsons organophosphate poisoning (Atropine) COPD (Ipatropium) Scopolamine is used for amnesia in OBGYN along with morphine
Atropine and tropicamide–> PSNS Antagonist
Characterise a atropine overdose
Dilation—> Blurred vision
Tachyarrythmia
Red b/c pix won’t sweat
Temp increase making them red
What medication is taken in the case of a atropine overdose?
Take reversible acting cholinergic agonist
Such as Edrophonium, Neostigmine, Physostigmine
Can acetylcholine be used as a drug?
No it cleaved by ACHe too fast
Symptoms of cholinergic drug overdose
Nausea, Vomiting, Flushing, Pupil constriction/ miosis, Diarrhea
Antidote for cholinergic overdose
atropine
symptoms of atropine poisoning
constipation, dry mouth, urinary retention, pupil dilation, myodriasis, Dry/ sandy eyes
Antidote for atropine poisoning
Physostigmine
Alpha 1 agonist
MOA
USE
SIDE EFFECTS
MOA: Stimulates vasoconstriction and may increase BP
Use: Cardiogenic shock( hypotensive state), septic shock, CHF
Side Effect: Orthostatic hypotension, tacharrythmias
Alpha 2 agonist
MOA
USE
Presynaptic they are auto regulatory Because a portion of NE will circle back and react with this receptor
A2 Stimulation—> Feedback inhibition of ongoing release of NE.
This inhibitory action decreases further action from the output from the adrenergic neutron
So this acts as a modulating mechanism for when there is high sympathetic activity.
USE= HYPERTENSION
B1 AGONIST
MOA
USE
Produces cardioslective stimulation increasing cardiac output.
Due to positive isotropy (leading to increased HR) and positive chronotropy (leading to increased heart contractility)
USE: Cardiogenic Shock and Heart Block
To speed up HR
CHF
B2 AGONIST
In bronchi and uterus stimulation occurs leading to bronchodilator and uterine relaxation
it is used in preterm labour and asthma
What is the first line treatment for cariogenic shock in ED
Adrenaline/ Epinephrine
It works by acting on all adrenergic receptors
Alpha 1 —> Increase total peripheral resistance at vasoconstriction
Beta 1——> Increases cardiac output plus a positive inotropic and chronotrophic effect
Drugs used in treatment for hypertension
Clonidine (A2 Agonist)
Nebivolol. (B1 Blocker)
Propranolol (Non-selective beta blocker)
Labetolol (A1, B1, B2)
Nasal decongestants
Class
MOA
Example: Phenylephrine, Oxymetazolone
MOA: They are alpha 1 and alpha 2 agonist that cause vasoconstriction and decrease congestion in nasal vessels
MOA of direct acting agonists
Thye bind to the adrenergic receptor without interacting with presynaptic neurone
Indirect acting agonist
They enhance norepinephrine release from the presynaptic terminals or inhibit norepinephrine uptake
Mixed Action Adrenergic agonist
They active postsynaptic adrenergic receptors and induce the release of NE from the presynaptic terminals
