Exam 2 Flashcards
Somatic nervous system controls what?
Voluntary muscle movements
Autonomic nervous system controls what?
Involuntary functions
What is included in the autonomic nervous system?
Sympathetic, parasympathetic and enteris
Sympathetic nervous system mediates what response?
Fight or flight
what does the fight or flight response do?
Increase HR, BP and Breathing
What does the parasympathetic nervous system mediate?
Rest and digest
what does rest and digest do?
conserve energy. slow HR and promote digestion
Parasympathetic nervous system involves primarily cranial nerve _____
- Vagus nerve
what is the enteric nervous system?
complex network of neurons controlling gastrointestinal functions
Parasympathetic nervous system has ____(longer/shorter) preganglionic and _____(longer/shorter) postganglionic fibers
longer
shorter
Sympathetic has ____(longer/shorter) preganglionic and _____(longer/shorter) postganglionic fibers
shorter
longer
Parasympathetic nervous system primarily uses ____ as a neurotransmitter, while sympathetic nervous system primarily uses _____
Acetylcholine
Norepi
____ receptors are mainly muscarinic and nicotinic, while ____ receptors are mainly alpha and beta adrenergic.
Parasympathetic
Sympathetic
_____ are clusters of neuron cell bodies in the sympathetic nervous system, located close to the spinal cord.
Chain ganglia
_____ are networks of neurons in the enteric nervous system, similar in function to the chain ganglia.
PNS plexi
What are sympathomimetics?
Drugs that mimic the effects of the sympathetic nervous system
What are parasympathomimetic (cholinomimetic)
Drugs that mimic the effects of the parasympathetic nervous system.
What are sympathoplegic (α and β blockers)?
Drugs that block the sympathetic nervous system.
What are parasympathoplegics (anticholinergics)
Drugs that block the parasympathetic nervous system.
List the sympathetic receptors, subtypes, and second messengers
Receptor: Adrenergic receptors
Subtype: Alpha and Beta
Second messengers: cAMP, IP3, DAG
List the parasympathetic receptors, subtypes and second messengers
Receptor: Cholinergic receptors
Subtype: Muscarinic and Nicotinic
Second messengers: cAMP, IP3, DAG
What are the adrenergic alpha receptor subtypes?
Alpha 1 and 2
What are the adrenergic Beta receptor subtypes?
Beta 1 and 2
What G protein is coupled with Alpha 1, Alpha 2, Beta 1 and Beta 2?
QISS
A1: Gq (activates phospholipase C)
A2: Gi (inhibitory..inhibit adenylate cyclase)
B1/B2: Gs (stimulates..increase cAMP)
Where are alpha 1 receptors found and what do they cause?
Vascular smooth muscle, causing vasoconstriction.
Where are the Alpha-2 adrenergic receptors found and what does this cause?
Presynaptic, inhibiting neurotransmitter release.
Where are the Beta-1 adrenergic receptors found and what does this cause?
Cardiac muscle, increasing heart rate and contractility.
Where are the Beta-2 adrenergic receptors found and what does this cause?
Vascular smooth muscle, causing vasodilation. Bronchi causing bronchodilation
Where are the Muscarinic cholinergic receptors found and what does this cause?
Smooth muscle (relax)
Heart (decrease HR and contractility)
Where are the Nicotinic cholinergic receptors found and what does this cause?
Skeletal muscle (muscle contraction.)
How does the autonomic (sympathetic and parasympathetic) feedback loop work in terms of MAP
Sympathetic: vasoconstriction, increase HR, increase contractile force, increase venous tone = increased BP
Parasympathetic: vasodilation, decrease HR = decrease BP
How does the hormonal feedback loop work in terms of MAP
Decreased blood pressure is sensed by the kidneys, leading to renin release, angiotensin II production, and aldosterone secretion to increase blood volume and pressure.
What are the organ system effects of stimulation of the parasympathetic system?
Slowed heart rate, bronchoconstriction, increased digestive activity.
What are the organ system effects of stimulation of the sympathetic system?
Increased heart rate, bronchodilation, decreased digestive activity.
describe how vasodilation occurs in skeletal muscle blood vessels.
vasodilation of skeletal muscle blood vessles via acetylcholine released from postganglionic parasympathetic fibers.
List the six main classes of neurotransmitters
1.esters of choline
2.monoamines
3.amino acids
4. purines
5. peptides
6. inorganic acids
Example of esters of choline neurotransmitter (1)
Acetylcholine
Example of monoamines neurotransmitter (3)
norepi
dopa
serotonin
example of amino acids neurotransmitter (2)
glutamate
gaba
example of purines neurotransmitter (2)
adenosine and ATP
example of peptides neurotransmitter (2)
substance P
endorphins
example of inorganic acids neurotransmitter (1)
nitric oxide
Recall the function of three CNS neurotransmitters in emotion.
Dopamine
Serotonin
Norepo
List three types of synapses described in lecture.
chemical synapses
electrical synapses
on-pause synapses.
Describe the possible fate of neurotransmitters in the synapse. (4)
- diffusion away from synapse
- degraded by enzymes
- uptake into pre-synaptic cell
- uptake into surrounding cells
What is the difference between excitatory and inhibitory neurotransmitters
Excitatory: Cause depolarization (e.g., glutamate).
Inhibitory: Cause hyperpolarization (e.g., GABA).
What role does CHT play in the presynaptic neuron?
Choline transporter into neuron
Describe the formation of acetylcholine
acetyl-CoA + choline via ChAT
Describe the transport of acetylcholine (specifically VAT)
VAT transports ACh into vesicle
Describe the enzymatic cleavage of acetylcholine
enzymatic cleavage occurs by acetylcholinesterase (AChE)
What is the SNARE complex?
Anchoring (docking). includes SNAP-25 and VAMP
List targets for drug action in the synapse. (5)
Synthesis
Storage
Release
Receptors
Degradation/Reuptake
What is an example of drug action for the synthesis synapse
Inhibition of tyrosine hydroxylase to block norepinephrine synthesis
What is an example of drug action for the storage synapse
Reserpine to inhibit vesicular storage of neurotransmitters
What is an example of drug action for the release synapse
Botulinum toxin to block neurotransmitter release
What is an example of drug action for the receptors synapse
Agonists and antagonists acting on muscarinic, nicotinic, alpha, beta, dopamine, and serotonin receptors
What is an example of drug action for the reuptake synapse
SSRI - reuptake inhibitor
List the major clinical uses of cholinomimetic agonists (cholinergic agonists). (4)
Acetylcholine - pupillary constriction
Methacholine - astha (Dx)
Carbachol - Decrease IOP
Bethanechol – Bladder dysfunction, GERD
Describe direct-acting cholinomimetic agent
Mimic activity of acetylcholine. (bind to and activate M or N receptors)
Describe indirect-acting cholinomimetic agent
Block acetylcholinesterase
The indirect cholinomimetic ______ is useful in the diagnosis of Myasthenia gravis
Edrophonium
Describe the differences between a nicotinic and muscarinic receptor.
Nicotinic receptors are ion channels
muscarinic receptors are G-protein coupled receptors.
List the effects of cholinomimetics in the major organ systems (eye, CV system, respiratory system and GI)
eye (pupillary constriction)
cardiovascular system (decreased peripheral resistance, increased heart rate)
respiratory system (bronchoconstriction)
gastrointestinal tract (increased secretions and motility).
What are the two different types of glaucoma?
Open-angle and closed-angle
Cholinomimetics are used for which type of glaucoma and contraindicated in what other type of glaucoma?
used for - open-angle
contraindicated for: closed-angle
List the major signs and symptoms of organophosphate insecticide poisoning
“SLUDGE-M”
salivation
lacrimation
urination
defecation
gastrointestinal motility
emesis
miosis
List the major signs and symptoms of acute nicotine toxicity.
tremors
vomiting
respiratory stimulation
convulsions
coma
What is the function of acetylcholinesterase?
Breaks down acetylcholine
what is the function of organophosphate aging?
organophosphates can irreversibly inhibit this enzyme through covalent binding and “aging”.
Antimuscarinics: main uses for the following according to lecture:
Atropine is for _____
Scopolamine is for ____
Tropicamide is for _____
Ipratopium is for _____
- bradycardia
- motion sickness
- eye
- COPD