ATI Pharmacology – Neurology Notes
The Nervous System:
• The nervous system has two main segments:
o The central nervous system
▪ Brain
▪ Spinal Cord
o The peripheral nervous system
▪ Motor system
• Afferent sensory nerves
o Send information to the spinal cord and brain
• Efferent motor nerves
o Carry signals from the brain to all parts of the body
▪ Autonomic nervous system
• Sympathetic nervous system
o Protects the body in times of danger and stress
• Para-sympathetic nervous system
o Maintains regulatory tasks of the body
• Brain
o Four lobes make up each hemisphere of the brain
▪ Frontal
▪ Temporal
▪ Parietal
▪ Occipital
o The cerebellum and the brain stem provide additional support to the brain and
its functions, and facilitate communication between the brain and other parts of
the body
o An interlocking network of neurons allows the brain to communicate to various
parts of the body via nerves in the spinal cord
o Chemical neurotransmitters stimulate neurons to send electrical impulses
from one neuron to the next
,• Neurons
o Cells that conduct nerve impulses in the central and peripheral nervous systems
▪ Cell body
• Contains cytoplasm, mitochondria, lysosomes, and other
structures necessary for the cell to survive
▪ Axon
• Thread-like structure that carries nerve impulses away from
the cell body
• Multiple appendages that reach out to dendrites on neighboring
cell bodies
, ▪ Dendrites
• Protrude from the cell body, receiving and carrying nerve
impulses to the cell body
▪ Synaptic cleft
• The space between the axon’s appendages and the neighboring
cell’s dendrites
• Electrochemical reactions release neurotransmitters across that gap
o This reaction occurs in response to the depolarization that
occurs when sodium and potassium ions are exchanged
across the axon membrane
o Calcium ions regulate the flow of ions through the
membrane.
o The axon of one neuron releases neurotransmitters onto
the dendrites of another neuron
▪ Acetylcholine
▪ Histamine
▪ Gamma-aminobutyric acid (GABA)
▪ Oxytocin
▪ Vasopressin
▪ Monoamines
• Dopamine
• Serotonin
• Epinephrine
• Norepinephrine
The Autonomic Nervous System
• Responsible for releasing the appropriate neurotransmitter in response to
stress or danger
• It also releases neurotransmitters that maintain regulatory functions of the body
o Digestion
o Elimination
o Reproduction
The Nervous System:
• The nervous system has two main segments:
o The central nervous system
▪ Brain
▪ Spinal Cord
o The peripheral nervous system
▪ Motor system
• Afferent sensory nerves
o Send information to the spinal cord and brain
• Efferent motor nerves
o Carry signals from the brain to all parts of the body
▪ Autonomic nervous system
• Sympathetic nervous system
o Protects the body in times of danger and stress
• Para-sympathetic nervous system
o Maintains regulatory tasks of the body
• Brain
o Four lobes make up each hemisphere of the brain
▪ Frontal
▪ Temporal
▪ Parietal
▪ Occipital
o The cerebellum and the brain stem provide additional support to the brain and
its functions, and facilitate communication between the brain and other parts of
the body
o An interlocking network of neurons allows the brain to communicate to various
parts of the body via nerves in the spinal cord
o Chemical neurotransmitters stimulate neurons to send electrical impulses
from one neuron to the next
,• Neurons
o Cells that conduct nerve impulses in the central and peripheral nervous systems
▪ Cell body
• Contains cytoplasm, mitochondria, lysosomes, and other
structures necessary for the cell to survive
▪ Axon
• Thread-like structure that carries nerve impulses away from
the cell body
• Multiple appendages that reach out to dendrites on neighboring
cell bodies
, ▪ Dendrites
• Protrude from the cell body, receiving and carrying nerve
impulses to the cell body
▪ Synaptic cleft
• The space between the axon’s appendages and the neighboring
cell’s dendrites
• Electrochemical reactions release neurotransmitters across that gap
o This reaction occurs in response to the depolarization that
occurs when sodium and potassium ions are exchanged
across the axon membrane
o Calcium ions regulate the flow of ions through the
membrane.
o The axon of one neuron releases neurotransmitters onto
the dendrites of another neuron
▪ Acetylcholine
▪ Histamine
▪ Gamma-aminobutyric acid (GABA)
▪ Oxytocin
▪ Vasopressin
▪ Monoamines
• Dopamine
• Serotonin
• Epinephrine
• Norepinephrine
The Autonomic Nervous System
• Responsible for releasing the appropriate neurotransmitter in response to
stress or danger
• It also releases neurotransmitters that maintain regulatory functions of the body
o Digestion
o Elimination
o Reproduction
