Pharmacology General Flashcards
How is the parasympathetic system innervated?
2 neurons/2 synapse, all are Ach/Nicotinic receptor, terminal synapse is Ach/Muscarinic receptor,
What does the parasympathetic system innervate?
Cardiac and smooth muscle, gland cells, nerve terminals
How is the sympathetic system innervated?
2 neurons/2 synapse (all Ach/Nicotinic). Terminal synapse: Mostly NE/alpha-beta adrenergic receptors (cardiac/smooth muscle, gland cells)
What are exceptions in the sympathetic nervous system with regards to terminal synapses?
Sweat glands (Ach/Muscarinic), Renal vasculature/smooth muscle (Dopamine/D1,D2), Adrenal medulla (direct release of epi/NE into bloodstream)
How is somatic nervous system innervated?
1 neuron/1 synapse (Ach/Nicotinic at NMJ)
Botulinum toxin
prevents neurotransmitter release at all cholinergic terminals
Nicotinic Ach receptors
Ligand gated Na/K channels (Nn autonomic ganglia; Nm in NMJ)
Muscarinic Ach receptors
GPCRs
alpha 1 receptor (G-protein class, functions)
Gq, increases vascular smooth muscle contraction/mydriasis/intestinal and bladder sphincter muscle contraction
alpha 2 receptor (GPCR, function)
Gi, decreases sympathetic outflow/insulin release/lipolysis, increases platelet aggregation
B1 receptor (GPCR, function)
Gs, increase heart rate/contractility/renin release/lipolysis
B2 receptor (GPCR, function)
Gs, Vasodilation, bronchodilation, increase heart rate/contractility/lipolysis/insulin release, decreases uterine tone/ciliary muscle relaxation, increases aqueous humor production
M1 receptor (GPCR, function)
Gq, CNS, enteric nervous system
M2 receptor (GPCR, function)
Gi, decrease HR/contractility of atria
M3 receptor (GPCR, function)
Gq, increase exocrine gland secretion (lacrimal, salivary,gastric acid), increase gut peristalsis/bladder contraction/bronchoconstriction, increase miosis (sphincter, accomodation (ciliary muscle)
D1 receptor (GPCR, function)
Gs, relaxes renal vascular smooth muscle
D2 receptor (GPCR, function)
Gi, modulates transmitter release esp in brain
H1 receptor (GPCR, function)
Gq, increase nasal/bronchial mucus production, increases vascular permeability, contraction of bronchioles, pruritus and pain
H2 receptor (GPCR, function)
Gs, increase gastric acid secretion
V1 receptor (GPCR, function)
Gq, increase vascular smooth muscle contraction
V2 receptor (GPCR, function)
Gs, increase water permeability and reabsorption in collecting tubules of kidney
Hemicholinium
blocks choline transporter–anticholinergic
Vesamicol
blocks ACh transport into vesicles
Botulinum
blocks SNARE prevents Ach release into synapse
Metyrosine
inhibits tyrosine hydroxylase (blocks tyrosine to DOPA conversion)
Reserpine
blocks VMAT, prevents transport of NE into vesicles
Bretylium and guanethidine vs amphetamine
block release vs promote release of NE
cocaine, tcas, amphetamine
block re-uptake of NE
release modulating receptors of NE
alpha 2–NE agonist, decreases sympathetic outflow; angiotensin 2 receptor increases NE release–>increase BP
Bethanechol
cholinomimetic agent–postop ileus, neurogenic ileus, urinary retention
carbachol
cholinomimetic: glaucoma, pupillary constriction, relief of intraocular pressure
pilocarpine
cholinomimetic: potent stimulator of sweat, tears, saliva, open-angle and closed angle glaucoma
resistant to AchE
pilocarpine
used in anticholinergic poisoning, penetrates CNS
physostigmine
what are some AchE inhibitors?
all of the -stigmine; donepezil, rivastigmine, galantamine (alzheimers); edrophonium
organophosphate poisoning
cholinergic (irreversibly inhibits AchE) poisning: DUMBBELSS: diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of skeletal muscle and CNS, lacrimation, sweating, salivation; antidote is atropine
muscarinic antagonist used in parkinsons
Benztropine
scopolamine
muscarinic antagonist used in motion sickness
muscarinin antagonist used in COPD, asthma
ipatropium, tiotropium
muscarinin antagonist used to reduce urgency in cystitis, reduce bladder spasms
oxybutynin, darifenacin, solifenacin
preop use to reduce airway secretions, drooling, peptic ulcers
glycopyyrolate; muscarinic antagonist
what to watch out for when using cholinergic medications?
increase of secretions: exacerbation of COPD, asthma, and peptic ulcers
what is the anti-ach toxidrome?
hot as a hare, dry as a bone, red as a beet, blind as a bat, mad as a hatter, bowel/bladder lose their tone, heart runs alone
plant alkaloids (jimson weed)
anticholinergic poisoning
epinephrine
Beta > alpha agonist; anaphylaxis, open angle glaucoma, asthma, hypotension; alpha effects predominate at high doses
norepinephrine
a1 > a2 > B1; use in hypotension but lowers renal perfusion
isproteronol
B1 = B2
dopamine
D1 = D2 > B > a
dobutamine
B1 > B2 > alpha
phenylephrine
a1 > a2
albuterol, salmeterol, terbutaline
B2 > B1
what are two sympatholytics?
clonidine and alpha-methyldopa–alpha2 agonists
sympatholytic used in pregnancy that can cause coombs+ hemolytic anemia and SLE like syndrom
alpha methyldopa
used preop for pheochromocytoma patients
phenoxybenzamine–alpha blocker used to prevent hypertensive crisis
given to patients on MAO inhibitors who eat tyramine containing foods
phentolamine–alpha blocker
selective a1 blockers
-osin endings; used in BPH, PTSD (prazosin); and HTN (except tamsulosin)
beta blocker that causes dyslipidemia
metoprolol
activates B3 receptors
Nebivolol–cardiac selective B1 blockade, stimulation of B3 activating NO synthase in vasculature