Drugs Affecting the PNS (Part 1) Flashcards
The autonomic nervous system innervates organs with _____.
Involuntary functions
Autonomic function = _____.
No control
Most organs have _____ control.
Dual, having inout from both the parasympathetic and sympathetic systems
What is the visible effect on organs at any given time?
The net input between the parasympathetic and sympathetic systems
Define resting tone.
The resting level of activity in the normal animal
The somatic nervous system innervates organs with _____.
Voluntary functions
Somatic function = _____.
Conscious control
The autonomic nervous system originates in the _____.
CNS
What regions of the body does the parasympathetic system originate from?
Craniosacral
What regionals of the body does the sympathetic system originate from?
Thoracolumbar
What does medullary outflow deal with?
Cranial nerves
What does sacral outflow deal with?
S2-S4 sacral spinal segments
What is included in craniosacral?
1: Medullary outflow
2: Sacral outflow
3: Long pre-ganglionic neuron
4: Short post-ganglionic neuron
What is included in thoracolumbar?
1: Spinal segments along the T-L region
2: Short pre-ganglionic neuron
3: Long post-ganglionic neuron
What is the pre-ganglionic neurotransmitter for the PSNS?
Acetylcholine (nicotinic)
What is the post-ganglionic neurotransmitter for the PSNS?
Acetylcholine (muscarinic)
What is the pre-ganglionic neurotransmitter for the SNS?
Acetylcholine
What is the post-ganglionic neurotransmitter for the SNS?
Norepinephrine
Where is acetylcholine released from?
Pre-ganglionic neuron
What is acetylcholine broken down by?
Cholinesterases
Where is norepinephrine released from?
Synaptic nerve endings
Where is epinephrine released from?
Adrenal glands
What are some the other important neurotransmitters we discussed?
1: Dopamine
2: Histamine
3: Serotonin
4: Nitrix Oxide (NO)
What are the important PNS receptors?
1: Cholinergic
2: Adrenergic
3: Other - Vasopressin
What are the subgroups of the cholinergic receptor?
1: Nicotinic
2: Muscarinic
What are the subgroups of the adrenergic receptor?
1: Alpha
2: Beta
Acetylcholine is a _____.
Agonist
Nicotinic receptors are _____.
Ionotropic receptors
Muscarinic receptors are _____.
Metabotropic receptors
What are the subtypes of nicotinic receptors we discussed?
Nm - Meuromuscular junction (NMJ)
Nn - CNS and autonomic ganglia
What effects do muscarinic receptor produce?
Parasympathomimetic effects
What are the subtypes of muscarinic receptors?
M1-M5
Which of the muscarinic receptors are stimulatory?
M1, M3 and M5
Which of the muscarinic receptors are inhibitory?
M2 and M4
What are the most common locations for M1 muscarinic receptors?
1: Smooth muscle of the GI tract
2: Smooth muscles of the urinary bladder
3: Myocardium
4: Exocrine Glands
What effects do M1 muscarinic receptors have on the smooth muscle of the GI tract?
1: Increase in gastric secretion
2: Smooth muscle contratcion
What effects do M1 muscarininc receptors have on the myocardium?
Decreases heart rate
What effects do M1 muscarinic receptors have on the exocrine glands?
Increase in exocrine secretions
What are the SLUDD signs?
1: Salivation
2: Lacrimation
3: Urination
4: Digestion
5: Defecation
Cathecholamines are _____.
Agonists
What are the alpha and beta receptor?
Metabotropic g-coupled receptors
What are the alpha receptors?
1: Alpha-1
2: Alpha-2
What are the beta receptors?
1: Beta-1
2: Beta-2
Describe the alpha-1 receptors.
1: Most common
2: Vascular smooth muscle
3: Vasoconstriction
4: Increase blood pressure (MAP)
5: Mydriasis
6: Sphincter contraction of urinary bladder and GI tract
7: Glycogenolysis
Describe the alpha-2 receptors.
1: Brain and spinal cord
2: Vascular endothelium
3: Endocrine organs
4: Decrease insulin
5: Decrease renin
6: Decrease NE release
7: Decrease pancreatic secretion
Describe the beta-1 receptors.
1: Myocardium
2: Adipose tissue
3: Increase heart rate
4: Increase cardiac contractility
5: Lipolysis
6: Smooth muscle relaxation
7: Increase renin – > Increase Blood pressure
Describe the beta-2 receptors.
1: Airway smooth muscle
2: Vascular smooth muscle
3: Bronchodilation
4: Vasodilation
5: Smooth muscle relaxation
6: Increase blood to skeletal muscle
7: Cycloplegia
8: Glycogenolysis
9: Increase insulin
10: Increase NE release
Antidiurectic hormone (ADH) and Arginine vasopressin (AVP) are _____
Vasopressin receptors
Where are Antidiurectic hormone (ADH) and Arginine vasopressin (AVP) synthesized?
Hypothalamus
Where are Antidiurectic hormone (ADH) and Arginine vasopressin (AVP) stored?
Pituitary
What are Antidiurectic hormone (ADH) and Arginine vasopressin (AVP) released from and what are they released into?
Vesicles into circulation
Why are Antidiurectic hormone (ADH) and Arginine vasopressin (AVP) released?
In response to extracellular fluid hypertonicity
What are the vasopressin receptors?
V1-V3
What are the main effects of Antidiurectic hormone (ADH) and Arginine vasopressin (AVP)?
1: Increases the amount of solute-free water reabsorbed back into circulation by renal tubular cells — > main site of action is collecting ducts
2: Arteriolar vasoconstriction —> increases peripheral vascular resistance (PVR) and mean arterial blood pressure (MAP)
Describe V1 receptors.
1: Vascular smooth muscle vasoconstriction and preferentially shunts blood to the CNS and heart
2: Aggregation of platelets
3: Inhibits renin release in juxtoglomerular cells
Describe V2 receptors.
1: Increase water permeability, aquaporins and urea ports in the renal collecting ducts
2: vWF release in endothelial cells
3: Aggregation of platelets
4: Vasodilation of vascular endothelium
Describe V3 receptors.
Negative feedback for ADH and stimulates ACTH release in pituitary gland
How are autonomic drugs classified?
1: Mimetics
2: Lytics
Define mimetics.
Drugs that stimulate (mimic) autonomic input or effects
Define lytics
Drugs that block (lyse) autonomic input or effects
Direct-acting autonomic drugs are _____ and _____.
Agonists and Antagonists
Direct-acting autonomic drugs act _____.
Directly on the receptor
Indirect-acting autonomic drugs have _____.
Non-receptor interactions
What are the sympathetic effects on the eye?
1: Relaxation of ciliary muscle
2: Contraction of the iris radial muscle
3: Decrease aqueous humor production
What are the parasympathetic effects on the eye?
1: Contraction of ciliary muscle
2: Contraction of the iris sphincter muscle
What are the sympathetic effects on the heart?
1: Increased heart rate
2: Increased contractility
3: Increased automaticity and conduction of AV node
What are the parasympathetic effects on the heart?
1: Decreased heart rate
2: Decreased contractility
3: Decreased AV node conduction
What are the sympathetic effects on the vasculature?
1: Vasoconstriction (Alpha-1 and V1)
2: Vasodilation (Beta-2 and V2)
3: Various vasoconstriction and vasodilation (Alpha-2)
What are the parasympathetic effects on the vasculature?
1: Indirect vasodilation through release of NO
What are the sympathetic effects on the the lung?
1: Bronchodilation (Beta-2)
2: Increase in cilia synchronicity (Beta-2)
3: Increase pulmonary blood flow (Beta-1)
What are the para sympathetic effects on the lung?
1: Bronchoconstriction
2: Increase respiratory secretions
What are the sympathetic effects on the GI tract?
1: Decrease motility
2: Closure of sphincters and increased tone
3: Inhibit secretion
(All by Alpha-1, Beta-1 and Beta-2)
What are the parasympathetic effects on the GI tract?
1: Increase motility
2: Relaxation of sphincters and decreased tone
3: Stimulate secretion
(All by M1)
What are the sympathetic effects on the urinary bladder?
1: Relaxation of detrusor muscle (Beta-2)
2: Contraction of internal urethral sphincter ( Alpha-1)
What are the parasympathetic effects on the urinary bladder?
1: Contraction of detrusor muscle
2: Relaxation of internal urethral sphincter
(All by M1)
