VIII - Adrenergic Pharmacology Flashcards
Primary neurotransmitter at the sympathetic post-ganglionic neuron effector cell synapses in most tissues
Norepinephrine
Sympathetic post-ganglionic neuron effector cell synapses use norepinephrine except
eccrine sweat glands, vasodilator sympathetic fibers in the skeletal muscle
Steps in Adrenergic Stimulation
synthesis, storage, release, termination
Adrenergic Stimulation: Step 1
SYNTHESIS - tyrosine is hydroxylated by tyrosine hydroxylase to DOPA which is decarboxylated to dopamine which is hydroxylated to norepinephrine
Adrenergic Stimulation: tyrosine hydroxylation is inhibited by
metyrosine
Adrenergic Stimulation: Step 2
norepinephrine and dopamine are transported into vesicles, MAOIs increase stores of NE and dopamine
Adrenergic Stimulation: vesicular transport is inhibited
reserpine
Adrenergic Stimulation: Step 3
entry of Ca triggers interaction among SNARE proteins (VAMPs and SNAPs)
Adrenergic Stimulation: inhibits interaction among SNARE proteins
guanethidine
Adrenergic Stimulation: promotes interaction among SNARE proteins
amphetamine, tyramine
Adrenergic Stimulation: Step 4
diffusion and reuptake via NET and DAT in the synaptic cleft, metabolized by MAO and COMT into metanephrines and VMA
Adrenergic Stimulation: diffusion and reuptake via NET and DAT is inhibited by
cocaine, TCAs
Adrenergic Stimulation: metabolism of norepinephrine into metanephrine and VMA is inhibited by
MAOIs, COMT Inhibitors
Cholinergic Inhibitors: Synthesis
hemicholinium
Cholinergic Inhibitors: Storage
vesamicol
Cholinergic Inhibitors: Release
botulinum
Cholinergic Inhibitors: Metabolism
neostigmine
Cholinergic Inhibitors: Reuptake
none
Adrenergic Inhibitors: Synthesis
metyrosine
Adrenergic Inhibitors: Storage
reserpine
Adrenergic Inhibitors: Release
guanethidine
Adrenergic Inhibitors: Metabolism
MAOIs, COMTIs
Adrenergic Inhibitors: Reuptake
cocaine, TCAs
Adrenoreceptors: effector tissues, smooth muscle, glands, Gq, inc. IP3, DAG, inc. Ca, contraction, secretion
Alpha 1
Adrenoreceptors: nerve endings, smooth muscles, Gi, dec. cAMP, dec. transmitter release, contraction
Alpha 2
Adrenoreceptors: cardiac muscle, JG apparatus, Gs, inc. cAMP, inc. heart rate and contractility, inc. renin
Beta 1
Adrenoreceptors: smooth muscle, liver, heart, Gs, inc. cAMP, relax smooth muscle, inc. glycogenolysis, inc. heart rate and contractility
Beta 2
Adrenoreceptors: adipose cells, Gs, inc. cAMP, inc. lipolysis
Beta 3
Adrenoreceptors: smooth muscle, Gs, inc. cAMP, relax renal vascular smooth muscle
Dopamine 1
Adrenoreceptors: contracts most vascular smooth muscle
Alpha 1
Adrenoreceptors: contracts pupillary dilator muscle
Alpha 1
Adrenoreceptors: contracts pilomotor smooth muscle
Alpha 1
Adrenoreceptors: inhibits adrenergic and cholinergic transmitter release
Alpha 2
Adrenoreceptors: stimulates platelet aggregation
Alpha 2
Adrenoreceptors: contracts some vascular smooth muscle
Alpha 2
Adrenoreceptors: inhibits lipolysis
Alpha 2
Adrenoreceptors: inhibits insulin release
Alpha 2
Adrenoreceptors: stimulates heart rate and forces
Beta 1, Beta 2
Adrenoreceptors: stimulates renin release from JG cells of the kidney
Beta 1
Adrenoreceptors: relaxes airway, uterine and vascular smooth muscle
Beta 2
Adrenoreceptors: stimulates glycogenolysis
Alpha 1, Beta 2
Adrenoreceptors: stimulates insulin release
Beta 2
Adrenoreceptors: causes tremors by stimulating somatic motor neuron terminals
Beta 2
Adrenoreceptors: stimulates lipolysis
Beta 3
Adrenoreceptors: dilates renal and other splanchnic blood vessels
Dopamine 1
Adrenoreceptors: inhibits adenylyl cyclase in nerve terminals
Dopamine 2
Activate adrenoreceptors directly and indirectly by increasing concentration of available catecholamines in the synapses (release of stored catecholamines, inhibition of reuptake)
Sympathomimetics
Epinephrine: Class
sympathomimetic - non-selective, direct-acting
Epinephrine: MOA
activates alpha 1 (vasoconstricion, increases BP), beta 1 (increased HR, conduction and contractility), beta 2 (bronchodilation)
Epinephrine: Uses
cardiac arrest, anaphylaxis, asthma, COPD, hemostasis
Epinephrine: Side Effects
hypertension, tachycardia, ischemia, hyperglycemia
Norepinephrine: Class
sympathomimetic - non-selective, direct-acting
Norepinephrine: MOA
activates alpha 1 (vasoconstricion, increases BP), beta 1 (increased HR, conduction and contractility), beta 2 (bronchodilation)
Norepinephrine: Uses
neurogenic shock, cardiogenic shock (last resort)
Norepinephrine: Side Effects
extreme vasospasm, tissue necrosis, excessive blood pressure increase, arrythmias, infarction, reflex bradycardia
Norepinephrine: Compensatory vagal reflexes tend to overcome
the direct positive chronotropic effects
Dopamine: Class
sympathomimetic - non-selective, direct-acting
Dopamine: MOA
activates alpha 1 (vasoconstricion, increases BP), beta 1 (increased HR, conduction and contractility), dopamine 1 (vasodilation of splanchnic and renal muscles)
Dopamine: Uses
shock, heart failure