Pharmacology - Autonomic Drugs Part 1 Flashcards
From which regions of the central nervous system do parasympathetic nerves originate?
Cranial and sacral regions
From which regions of the central nervous system do sympathetic nerves originate?
Thoracic and lumbar regions
What types of nerves arise from the spinal cord and innervate skeletal muscle directly?
Somatic nerves
How many neurons are involved in parasympathetic transmission from the spinal cord to the target organ?
2
True or False? Craniosacral parasympathetic axons synapse on neurons in the peripheral ganglia.
True
What neurotransmitter mediates parasympathetic nervous system function?
Acetylcholine
What neurotransmitter receptor mediates parasympathetic nervous system function at the peripheral ganglia?
Nicotinic acetylcholine receptors
What neurotransmitter receptor mediates parasympathetic tone in the cardiac muscle?
Muscarinic acetylcholine receptors (specifically, M2)
What neurotransmitter receptor mediates parasympathetic tone in the smooth muscle?
Muscarinic acetylcholine receptors (specifically, M3)
What neurotransmitter receptor mediates parasympathetic tone in the glandular cells?
Muscarinic acetylcholine receptors (specifically, M1 and M3)
Somatic nerves that arise from the spine innervate skeletal muscle. What neurotransmitter receptor, which is located on skeletal muscle, receives this input?
Nicotinic acetylcholine receptors
How many neurons are involved in sympathetic transmission from the spinal cord to the target organ?
2
Where is the first synapse after the spinal cord in sympathetic innervation of an organ?
Preganglionic sympathetic axons synapse on neurons in the paravertebral ganglia
True or False? Preganglionic sympathetic axons synapse on neurons in the peripheral ganglia.
False; preganglionic sympathetic axons synapse on neurons in the paravertebral ganglia
At the paravertebral ganglia, the neurotransmitter _____ acts on _____ receptors to mediate sympathetic nervous system function.
Acetylcholine; nicotinic acetylcholine
What neurotransmitter mediates sympathetic nervous system function at the sweat glands?
Acetylcholine
What neurotransmitter receptor mediates sympathetic nervous system function at the sweat glands?
Muscarinic acetylcholine receptors
What neurotransmitter mediates sympathetic tone in the cardiac muscle, smooth muscle, and glandular cells?
Norepinephrine
What are four cell types in which α- and β-adrenergic receptors mediate sympathetic tone?
Cardiac muscle, smooth muscle, glandular cells, and terminal ends of neurons
What neurotransmitter mediates sympathetic tone in the renal vascular smooth muscle?
Dopamine
What neurotransmitter receptor mediates sympathetic tone in the renal vascular smooth muscle?
D1 receptors
What two substances are released into the blood from the adrenal medulla after the activation of the sympathetic nervous system?
Epinephrine and norepinephrine
How many synapses are involved in activation of the adrenal medulla?
One; the adrenal medulla releases epinephrine and norepinephrine into the blood
Are nicotinic acetylcholine receptors ligand-gated sodium-potassium channels or G-protein coupled receptors?
Nicotinic receptors are ligand gated sodium-potassium channels
Are muscarinic acetylcholine receptors ligand-gated sodium-potassium channels or G-protein-coupled receptors?
Muscarinic acetylcholine receptors are G-protein-coupled receptors that act through second messengers
To what class of G-proteins are α1-receptors linked?
q
To what class of G-proteins are α2-receptors linked?
i
To what class of G-proteins are β1-receptors linked?
s
To what class of G-proteins are β2-receptors linked?
s
To what class of G-proteins are M1-receptors linked?
q
To what class of G-proteins are M2-receptors linked?
i
To what class of G-proteins are M3-receptors linked?
q
To what class of G-proteins are D1-receptors linked?
s
To what class of G-proteins are D2-receptors linked?
i
To what class of G-proteins are H1-receptors linked?
q
To what class of G-proteins are H2-receptors linked?
s
To what class of G-proteins are V1-receptors linked?
q
To what class of G-proteins are V2-receptors linked?
s
What are the major effects of α1-receptor activation?
It increases vascular smooth muscle contraction, and increases pupillary dilator muscle contraction (mydriasis)
What are the major functions of α2-receptor activation?
It decreases sympathetic outflow and decreases insulin release
What are the major functions of β1-receptor activation?
It increases heart rate and contractility, increases renin release from the kidneys, and increases lipolysis of adipose tissue
What is the major function of β2-receptor activation on the body’s vasculature?
Vasodilation
What is the major function of β2-receptor activation on the respiratory system?
Bronchodilation
What effect does β2-receptor activation have on glucagon release?
It increases glucagon release
Where are M1-receptors located?
The central nervous system
What effect does M2-receptor activation have on cardiac function?
It decreases heart rate and contractility
What are the effects of M3-receptor activation?
Increased exocrine gland secretions, gut peristalsis, bladder contraction, bronchoconstriction, miosis, and accommodation
What effect does D1-receptor activation have on renal vasculature?
It relaxes renal vascular smooth muscle
What are the effects of H1-receptor activation?
Pruritis, pain, nasal and bronchial mucus production, contraction of bronchioles
What is the effect of H2-receptor activation?
It increases gastric acid secretion