Pharm exam #2 Flashcards
Sympathetic Activity of β1
Renin release.
Accelerates SA node.
Increases heart contractility.
Relaxes skeletal blood vessels.
Sympathetic Activity of β2
Relax GI smooth muscle wall. Relax bladder. Glycogenolysis (glycogen converted to glucose) in liver. Accelerates SA node. Increases heart contractility. Relax bronchiolar smooth muscle.
Sympathetic Activity of α1
Contract smooth muscle vessels.
Glycogenolysis in liver.
Contract GI sphincter.
Contract urinary sphincter.
Sympathetic Activity of α2
Contract smooth muscle vessels.
Glycogenolysis in liver.
Relax wall of GI smooth muscles.
Parasympathetic activity of M2
Decelerates SA node.
Decreases heart contractility.
Parasympathetic activity of M3.
Relax smooth muscle of blood vessels. Contract bronchiolar smooth muscle. Contract wall of GI smooth muscles. Relaxt GI sphincter. Increase GI tract secretions. Contract bladder. Relax urinary sphincter.
SNS origin of fibers
Thoracolumbar region of spinal cord
SNS length of fibers
Short pre-ganglionic and long post-ganglionic; Has chain ganglion that can effect multiple effector organs with one stimulus
SNS Location of ganglia
Close to the spinal cord
PSNS origin of fibers
Brain and sacral spinal cord; craniosacral
PSNS length of fibers
long preganglionic and short postganglionic
PSNS location of ganglia
in the visceral effector organs
Acetylcholine
Direct cholinomimetic (parasympathomimetic).
Ester of choline. Made from acetyl Coa and choline, formed by CHAT (Choline acetyl transferase).
All pre-ganglia release this.
Permanently charged, so insoluble in lipids. Has to be given injected bc it cannot be absorbed very easily.
Miosis (pupillary constriction, short term- metabolism is 5-20 seconds), decreases IOP, (Binds to M1 sphincter receptor on eye); Contraction- prolonged can cause flaccid paralysis (On Nm of NMJ)
Methacholine
Direct cholinomimetic (parasympathomimetic).
Ester of choline (poor absorption & distribution in CNS).
Permanently charged, so insoluble in lipids. Has to be given injected bc it cannot be absorbed very easily.
Dx of asthma.
Sticks around (3x) longer than Ach bc it is not broken down as readily by enzymes.
Carbachol
Direct cholinomimetic (parasympathomimetic).
Ester of choline, derivative of Methacholine.
Resistant to hydrolysis
Miosis, decreases IOP (Binds to M1 sphincter receptor on eye)
Bethanechol
Direct cholinomimetic (parasympathomimetic).
Ester of choline, derivative of Methacholine.
Works on M3 receptor in GU, causes contraction of bladder, opens sphincter.
Resistant to hydrolysis.
Bladder dysfunction, GERD.
Muscarine
Direct cholinomimetic (parasympathomimetic). Less completely absorbed than other alkaloids bc it is charged. Elimination is enhanced in the kidneys by acidity.
Plant Alkaloids.
Pilocarpine
Direct cholinomimetic (parasympathomimetic).
Well absorbed. Elimination is enhanced in the kidneys by acidity.
Plant Alkaloids.
Edrophonium
Indirect cholinomimetic (parasympathomimetic).
Blocks acetylcholinesterase.
Simple Alcohol - fast duration 5-15 minutes
Acts on M3 receptor in GI; increases digestion, improves illius.
Myasthenia Gravis diagnosis
Neostigmine, Physostigmine
Indirect cholinomimetic (parasympathomimetic).
Blocks acetylcholinesterase.
Carbamates - moderate
Acts on M3 receptor in GI; increases digestion, improves illius (post op bc it out competes paralytics).
Treatment of Myasthenia Gravis, surgical paralysis reversal
Duration 0.5 to 2 hours
Echothiophate
Indirect cholinomimetic (parasympathomimetic).
Blocks acetylcholinesterase.
Organophosphates - days
Glaucoma, only useful drug to help bc the duration of action is 100+ hours compared to other drugs- it is irreversibly bound to that receptor
Atropine
Cholinoreceptor blocker (parasympatholytic)
Antimuscarinic
Plant-based alkaloid from the belladona plant or jimsomweed.
L-isomer is 100x more potent than D-isomer
Use: Organophosphate poisening (with pralidoxime), bradycardia.
Blocks nicotinic-muscarinic receptors so that they cannot lose their fluid through the canal of schlemm by relaxing cilliary muscles- so be careful with giving this with glaucoma, especially closed-angle. Also be careful with elderly men and those with a history of BPH, as atropine can prevent urination.
Scopolamine
Cholinoreceptor blocker (parasympatholytic)
Antimuscarinic
Plant-based alkaloid from henbane. Similar in chemical nature to atropine.
Use: Motion sickness.
Tropicamide
Cholinoreceptor blocker (parasympatholytic) Antimuscarinic Mydriasis (cilliary muscle dilation- what you'd use at eye doc bc duration is 1/4 of a day and not DAYS like other drugs) and cycloplegia diagnosis
Ipratromine
Cholinoreceptor blocker (parasympatholytic)
Antimuscarinic
Atrovent
Asthma
Phentolamine
Sympatholytic
Alpha Blocker
Reversible
alpha 1, alpha 2 non selective
reduces peripheral resistance, some cardiac stimulation (due to blocking of alpha 2 receptors on nerves, limiting reuptake of NE and increasing NE)
Hypertension (r/t Pheochromocytoma), cardiac stimulent
Can also be used to treat male erectile dysfunction, but only if nothing else works. Not front line for this. You could directly inject it into the penis, but that could cause priapism.
Prazosin
Sympatholytic Alpha Blocker Reversible Alpha 1 highly selective Low affinity to alpha 2 Relaxes arterial and venous smooth muscle Hypertension, BPH
Yohimbine
Sympatholytic
Alpha Blocker
Reversible
alpha 2, sexual dysfunction