ANS Flashcards
The results of cholinergic stimulation are:
1) Decreased HR
2) Bronchoconstriction
3) Sweating
4) Increased Salivation and GI secretion
5) Diarrhea/Vomiting
6) miosis - sm pupils.
The results of Adrenergic Stimulation are:
1) Increased HR(chronotropy)
2) Increased strength of myocardial contraction (inotropy)
3) Bronchodilation
4) Dilates Skeletal muscle vessels, Constricts muscles of skin and gut.
5) Relaxes GI tract muscles.
6) Contracts sphincters
7) Lg pupils (mydriasis)
8) Gluconeogenesis, Glycolysis
Where are Alpha1 receptors found & what is the result of stimulation?
1) Vascular smooth muscle - vasoconstriction of skin and GI vascular beds
2) Sphincters of the Gi Tract - contraction of GI urinary sphincters.
3) Radial muscle of the eye - dilation of iris
Where are Alpha2 receptors found & what is the result of stimulation?
1) Walls of GI tract - relaxation
Where are Beta1 receptors found & what is the result of stimulation?
1) Heart - Increases Heart Rate and strength of contraction.
Where are Beta2 receptors found & what is the result of stimulation?
1) Bronchioles - bronchodilation (alupent)
2) Some Vascular Smooth Muscle - Uterine Relaxation, Gluconeogenesis, Glycogenolysis.
What is a parasympathomimetic? Give examples
- Substance that sort-of mimics ACh.
ex. pilocarpine, neostigmine
What is a parasympatholytic? Give examples
- Substance that sort-of releases parasympathetic stimulation
ex. Anticholinergics: Atropine, scopolamine (Bella Donna), Donnatol (a GI antispasmodic).
What is a sympatholytic? Give examples
Blocks sympathetic stimulation
Examples:
1) Reserpine - blocks synthesis or storage of norepi in nerves.
2) Guanethine - blocks release of norepi
3) Phentolamine/Prazosin - Alphablocker
4) Propanolol (Inderal) - beta blocker (1>2)
What is a sympathomimetic? Give examples
Mimics sympathetic stimulation.
Examples:
1) Ephedrine, amphetamine - release norepi from storage vesicles. (alpha/beta)
2) Isoproterenol (beta 1 mimic at lower doses)
3) Alupent mimics beta2
4) Neosynephrine mimics alpha stimulation
What Drugs would cause inhibition of the ACh esterase?
malathion, neostigmine
What is myasthenia gravis?
Autoimmune disorder - antibodies against neuromuscular synaptic Ach receptors. -> NO stimulation to muscle fibers. Tested with tensilon.
Treated with Pyridostigmine(ACh esterase inhibitor)
What are the 6 ways medication can interfere with ACh stimulation?
1) Deplete ACh stores by repeated depolarization/exhaustion
2) Block release of ACh ex. Botulism
3) Competition for ACH receptors
ex.Succinylcholine - depolarizes
Curare/Vecuronion/Atracurium - blocks
depolarization
4) Chemicals like ACh that are NOT degraded
by ACh esterase. ex. Nicotine
5) ACh esterase inhibitors - leave increased
amounts of ACh in the synaptic cleft for
a longer time. ex. Malathion (irreversible),
Pysostigamine, Neostigmine.
6) Blocks the reuptake of neurotransmitter.
ex. SSRI selective serotonin Reuptake
Inhibitor = Prozac.
Beta-1 receptor
heart & kidney
blockade decreases heart rate, contractility, and sympathetic activity and decreases renin release
Beta-2 receptor
lungs, liver, pancreas, arteriole smooth muscle
blockade causes bronchospasm and vasoconstriction, decrease insulin secretion
alpha-1 receptor
arteriols
blockade causes arterial smooth muscle relaxation, vasodilation
Agonist
CAUSES AN ACTION.
An agonist is a chemical that binds to some receptor of a cell and triggers a response by that cell. Agonists often mimic the action of a naturally occurring substance.
Antagonist
Blocks the action of the agonist
Lidocaine
Blocking the fast voltage gated sodium (Na+) channels in the neuronal cell membrane that are responsible for signal propagation. membrane of the postsynaptic neuron will not depolarize and will thus fail to transmit an action potential. This creates the anaesthetic effect by not merely preventing pain signals from propagating to the brain but by stopping them before they begin.
What vaso active substance can increase capacitance or compliance?
Nitroglycerin
Sodium Nitroprusside
