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322 Cards in this Set

  • Front
  • Back
The two major branches of the Nervous system is?
PNS, CNS
The PNS is composed of?
ANS, and Somatic NS
The Autonomic nervous system is composed of?
Sympathetic NS and Parasympathetic NS
The CNC is made up of the?
Brain and Spinal cord
The brain is make up of what 3 sections?
Forebrain, Midbrain, and Hindbrain
The Forebrain makes up what?
Telencephalon
The midbrain forms the?
Diencephalon
The telencephalon is composed of what 4 parts of the brain?
Crebral Cortex, Basal Ganglia, Hippocampus, Amygdala
The diencephalon is composed of what?
Thalamus, Hypothalamus
The midbrain makes up the?
Mesencephalon
The Mesencephalon is make up of?
Tectum, Tegmentum
The Hindbrain is made up of what?
Metencephalon, and Myencephalon
The metencephalon is composed of?
Pons, Cerebellum
The Myelencephalon is composed of?
Medulla
There are how many pair of spinal nerves?
31 pairs
There are how many pairs of crainial nerves?
12
The peripheral Nervous System is made up of what?
31 PAIRS SPINAL NERVES, 12 pairs of cranial nerves
The PNS is divided into what two sections?
Somatic and Autonomic
The somatic and autonomic NS both have _________ and ________ neurons.
Sensory, motor
In the CNS, collections of neurons are called?
Neuclei
In the PNS, collections of neurons are called?
Ganglia
In the CNS, collections of axons are called?
Tracts
In the PNS, collections of axons are called?
Nerves
What are the three major levels of the CNS functions?
Spinal cord, Lower brain, and Higher brain or cortical level
The section of the CNS functions in walking circuits, withdrawal circuits, support against gravity circuits, and circuits for reflex control of organ function is called?
The spinal cord
The Lower brain level contains?
Medulla, pons, mesencephalon, hypothalamus, thalamus, cerebellum, and basalganglia
This portion of the CNS controls subconscious body activities such as arterial pressure, respiration, equilibrium, feeding reflexes, and emotional patters is called?
The lower brain level
This portion of the CNS functions as a large memory storehouse?
The higher brain or cortical level
This is essential for thought processes?
The higher brain, or cortical level
Each portion of the NS performs specific functions, but it is the __________ that opens the world up for one's mind and makes us who we are.
The higher brain or cortical level
The basic functional and structural unit of the CNS is called?
Neuron
Neurons store energy as glycogen, thus requiring constant blood flow for glucose supply. True or false
False
A junction connected between two neurons is called?
Synapse
This allow communication of nerve impulses via chemical (neurotransmitters) or electrical signals (gap junctions) is called a?
Symapse
Chemical symapses allow _____________ transmission of signal.
One-way
This secretes the neurotransmitter and is sending information is called?
Presynaptic neuron
Clusters of cell bodies or somas in the CNS is called?
Nuclei
Clusters of cell bodies or somas in the PNS is called?
Ganglia
Impulses arise on the neuron where?
Axon Hillock
The end of the axon terminal is called?
presynaptic knobs, or boutons
These are small knobs at the end of the axon that release chemicals called neurotransmitters?
Terminal buttons
The terminal buttons form the what?
Presynaptic neuron of the synapse
Another term used for presynaptic terminal button is what?
End bulb
Presynaptic membranes contain voltage-gated ___________ channels?
Calcium
The release of the neurotransmitter from the presnaptic membranes is done by?
Exocytosis
The receptor component binds to the transmitter itself is called?
Binding component
This receptor component either opens an ion channel or activates a second messenger system is called?
Ionophore component
Cation channels most often allow __________ ions?
Sodium
Anion channels allow _______ ions to pass?
Chloride
Transmitters that open sodium channels excite the?
Postsynaptic neuron
Transmitters that open chloride channels inhibit the?
Postsynaptic neuron
These channels excite the postsynaptic neuron?
Sodium channels
These channels inhibit the postsynaptic neuron?
Chloride channels
About 75% of the second messenger activators are tranduced with _______ coupled receptors.
G-protein
These are chemical substances that function as synaptic transmitters?
Neurotransmitters
Small molecules like acetylcholine, norepinephrine, dopamine, serotonin, GABA, glycine, glutamate, or NO are called?
Neurotransmitters
Thse molecules (endorphins, enkephalins) cause more prolonged actions than neurotransmitters is called?
Neuropeptides
Dendrites transmit signals by?
Electrotonic conduction
The effect of acidosis __________ neuronal activity and will ________________.
Depresses, Induce coma
The effects of alkalosis will ___________ neuronal excitability and will ________________.
Increases, Induce seizures
Myelin is produced in the PNS by?
Schwann cells
Myelin is produced in the CNS by?
Oligodendrocytes
This cell wraps around a single axon many times is called?
Schwann cells
The cell membrane of schwann cells is called?
Neurolemma
These myelin producing cells cover many axons in the CNS?
Oligodendrocytes
Myelinated axons in the CNS is made up of?
White matter
An example of a demyelinating disease is called?
Multiple scleerosis
A nerve impolse is said to jump form node to node is called?
Saltator conduction
The majority of the CNS neurons is made up of?
Multipolar neurons
An example of Multipolar neurons are?
Motor neurons
An example of a bipolar neuron is a ?
Sensory neuron
Unipolar neurons are also called?
Pseudounipolar neurons
This neuron is a single short process that divides like a T forming a longer process is called a?
Unipolar neurons
These pave cell bodies outside the CNS in the posterior root ganglia of spinal and cranieal nerves?
Unipolar neurons
Impulses FROM sensory receptors INTO the CNS is called?
Sensory or AFFERENT neurons
An example of a sensory afferent neuron is?
Pseudounipolar or unipolar neurons.
Exception, special senses which are bipolar neurons
These neuron conduct impulses OUT of CNS TO effector organs (muscles, gland) is called?
Motor or EFFERENT neurons
What are two types of motor neurons?
Somatic motor neuron and autonomic motor neurions
These neurons are responsible for reflex and voluntary control of skeletal muscles?
Somatic motor neurons
These innervate involuntary effectors (smooth muscle, ardiac muscle, and glands) is called?
Autonomic motor neurons
These neurons are found ENTIRELY in the CNS and are typically multipolar are called?
Interneurons or association neurons
The CNS is composed of the _________ and ________.
Brain, Spinal cord
The PNS is made up of?
Cranial and Spinal nerves, their receptors and effector endings.
These Somatic nervous system neurons control skin, muscles, and joints?
Sensory neurons
These neurons control skeletal muscles?
Motor neurons
This system is repsponsible for involuntary innervation of varous organ systems?
Autonomic Nervous System
The ANS has what type of neurons?
Sensory and Motor
These neurons control smooth and cardiac muscles?
Motor neurons
Nervous tisues consists of two principal types of cells called?
Neurons and glial (neuroglial) cells
The functional unit in the nervous system is?
neuron
Neurons are capable of cell devision? True or False
False
Neurons in the CNS are clustered into groups called?
Nuclei
Neuron cell bodies in the PNS occur in clusters called?
Ganglia
These conduct electrical signals TOWARD the cell body is called?
Dendrites
Dendrites conduct action potentials through the cell body? True, False
False
Generally, there is only one of these seen on a neuron?
Axon
Axons with the largest diameters conduct impulses more _________.
Rapidly
This portion of the neuron conducts impulses away from the cell body?
Axon
Protein synthesis occurs in which portion of the neuron?
Cell body (Perikaryon or Soma)
This portion of the neuron is termed the trigger zone, where nerve impulses arise is called?
Axon Hillock
Axon end with fine branching called ________________, that is also called _____________.
Axon terminals
Synaptic buttons or presynaptic knobs
This portion of the neuron is is where neurotransmitters are released as a result of an action potential which travels down the axon?
Synaptic buttons or presynaptic knobs
Bundles of nerve processes or fibers which are comprised of dendrites and axons are calle what in the PNS?
Nerves
Bundles of nerve processes or fibers which are comprised of dendrites and axons are called what in the CNS?
Tracts
Axons that are smaller than 2 micrometer are usually myelinated or unmyelinated?
Unmyelinated
This electrically insulates the axon?
Myelin sheath
These cells form the myelin sheath in the PNS?
Schwann cells
The cell membrane of Schwann cells is called?
Neurilemma
Myelin sheath is form by what type of cells in the CNS?
Oligodendrocytes
This myelin sheath wraps around only one axon at a time?
Schwann cells
These cells that make up the myelin sheath covers many axons instead of only one is called?
Oligodendrocytes
What portion of the CNS in the brain is composed on myelinated axons?
White matter
Gaps in the myelin sheath is called?
Nodes of Ranvier
All active Na+ channels of a nerve are consentrated at the?
Nodes of Ranvier
This acts as a insulator to prvent almost all leakage of charge of a neuron?
Myelin
Nerve impulse corrent can pass through the menbrane of myelinated axon only at?
The nodes of Ranvier
Action potentials that move from one node of Ranvier to the next node whre it triggers another action potential is termed?
Salutatory conduction
The electrical signal appears to jump from node t onode along an axon is termed?
Salutatory conduction
The structural classification of neurons is based on what?
Number of processes extending from the cell body
The most common type of neuron is?
Multipolar neurons
Thes neurons constitute the majority of CNS neurons?
Multipolar neurons
These neurons are characteried by having several dendrites and one axon extending from the body of the soma is called?
Multipolar neurons
A good exampoe of multipolar neurons is?
Motor neurons
These neurons have two processes, an axon and dendrite that extend from opposite ends of the cell body is called?
Bipolar neuron
Thise neurons act as receptor cells in the retina, ear, and olfactory mucosa is called?
Bipolar neurons
These neurons are also called pseudounipolar neurons?
Unipolar neurons
These neurons are found chiefly in the PNS where they function as sensory neurons is called?
Unipolar neurons
Cel bodies of sensory neurons are located where?
Outside the CNS in the posterior root ganglia of the spinal nad cranial nerves
Thse neurons conduct impulses FROM sensory receptors INTO the CNS is called?
Sensory or AFFERENT neurons
The second major type of cell found in the CNS is the?
Neuroglial or glial cell
Thse cells do not participate in neuronal signaling?
Neuroglial cells
What are the two distinct types of astrocytes?
Fibrous astrocytes, Protoplasmic astrocytes
This type of astrocyte glial cell is found only in the white matter?
Fibrous astrocytes
This type of astrocyte (glial cell) is found only in the Gray matter?
Protoplasmic astrocytes
These type of cells have multiple processes that radiate from the cell producing a characeristic star-shaped appearance?
Astrocytes
These type of cells induce capillaries to form the tight junctionns that form the blood-brain barrier?
Astrocytes
These cells provide structural neuronal support?
Astrocytes
These cells are active in repair following injury to the brain?
Astrocytes
These cells form the myelin sheath of axons in the brain and spinal cord?
Oligodendrocytes
These cells are capable of myelinating more than one axon?
Oligodendrocytes
There are the smallest neuroglial cells?
Microglial cells
These type of cells are transported throught the CNS to sites of neuronal injury or degeneration where they proliferate and develop int olarge marcrophages that phagocytie neuronal debris?
Microglial cells
These cells phagocytize neuronal debris?
Macrophages
These cells are ciliated, cuboidal glial cells that line the roof of the third and fourth ventricle of the brain and the central spinal canal and secretes cerebrospinal fuid?
Ependymal cells
This is used to effectively isolate the brain and spinal cords extracellular compartments from the intravascular compartments ensuring that the brain's environment remains stable?
Blood-Brain Barrier
The BBB is formed by?
Endothelium cells of cerebral capillaries nad choroid plexus epithelium
There are 4 midline brain structures that lack the blood-brain barrier, they are collectively know as?
Circumventricular organs
The chemoreceptor zone that initiates vomiting in response to chemical changes in the plasma, also concerned with cardiovascular control is known as?
Area Postrema
The BBB is completely or incompletely developed in teh newborn
Incompletely
Bile pigments in the undeveloped BBB of an infant may enter the basal ganglia and produce?
Kernicterus
The integrity of the BBB can be compromised by?
Traumatic head injury
Subarachnoid or intracerebral hemorrhage
Cerebral ischemia, lesions, infection, irradiated sites
What are the three essential functions of the nervous system?
Receove sensory information
Integrate & interpret information
Initate motor responses
This is the conscious, subconscious, or unconscious awareness of external and internal stimuli?
Sensation
What are the levels of CNS translation for sensation?
Spinal reflexes (deep tendon reflexes)
Visceral reflexes (brainstem) - unconscious
Crude identification (Thalamus)
Precise identification (cerebral cortex) - fine touch, tictile
Each specific type of sensation is called a?
Sensory modality
The distinct quality that makes one sensation different from another sensation is called?
Modality
A given sensory neuron carries only ______ modality.
One
Each of the principle types of sensation (touch, pain, sight, hearing(sound)) is called?
Modality of sensation
Each receptor is responsive to one type of stimulus energy. Specificity is a key property of a receptor, it underlines the most important coding mechanism called the?
Labeled line principle
This is a change in sensitivity, usually a decrease, to a long-lasting stimulus is called?
Adaptation
pressure, touch, and smell receptors that adapt quickly and play a major role in signaling changes in a stimulus is called?
Fast-adapting (phasic) receptors
Pain, proprioceptors, nad chemoreceptors adapt slowly. These receptors are important in signaling information regarding the stedy state of the body is called?
Slow-adapting (tonic) receptors
Somatosensory pathways are what type of pathways?
Afferent
These pathways are going from the receptor, up the spinal cord (ascending tracts) to the brain stem and/or brain are called?
Somatosensory pathways
The pathways carry sensory input up the cord from the body to the brain are called?
Somatosensory pathways
These pathways transmit temperature, pain, pressure, touch, vibratory sense, and proprioception are called?
Somatosensory pathways
There are 3 different modalities of the somatosensory system, what are they?
Discriminative touch
Pain and temperature sensations
Proprioception or position sense
The perception of pressure, vibration, and texture is referred to as?
Discriminative touch
Fast adapting with small receptive fields to signify the beginning and end of fine touch is what type of recetor?
Meissner's corpuscle
Fast adapting with large receptive fields for signifying the beginning and enf of gross touch is called?
Pacinian corpuscle
Slow adapting with small receptive fields to signify sustained and fin touch is called?
Merkel's disk
Slow adapting with large receptive fields to signify sustained and gross touch is called?
Ruffini's ending
What two types of touch receptors are rapidly adapting? Meissner's, Merkel's disks, Pacinian corpuscles or Ruffini endings?
Meissner's corpuscles, Pacinian corpuscles
What two types of discriminative touch are slowly adapting? Meissner's corpuscles, Merkel's disks, Pacinian corpuscles, Ruffini endings
merkel's disks, Ruffini endings
These receptors respond to temperatures between 10 and 35 C?
Cold receptors
Therse receptors respond to temeratures between 30 and 45 C?
Warm receptors
These receptors guage the force generated by a muscle by measuring the tension in the tendon?
Golgi tendon organs
These receptors respond to strong pressure from a sharp object?
Mechanical nociceptors
These receptors respond to buring heat or extreme cold?
Thermal nociceptors
These receptors respond to a combination of mechanical, thermal, and chemical stimuli?
Polymodal nociceptors
Pain and temperature have specialized receptor organs. True or False.
False
What type of receptors are used for pain and termperature?
Free nerve endings
Nociceptors - for pain
Thermoreceptors - for temp
These receptors are found throughout the skin, mscle, bone, and connective tissue?
Nociceptors and thermoreceptors
Pain is the result of damage to?
Free nerve endings
Most pain is the reult of the release of what type of substances by damaged tissues?
Prostaglandins, Histamine, Substance P
The major stretch receptors in the muscles is called?
Muscle spindle
Larger nerves tend to be myelinated or unmyeliniated?
Mieliniated
Smaller receptors tend to be myelinated or unmeilinated?
Unmyelinated
Skeletal muscle tend to have what type of nerve fibers?
A-alpha
Muscle spindle tend to have what type of nerve fibers?
A-gamma
Sympatheetic fibers are what type of nerve fibers?
Unmyelinated Type C fibers
Myelinated nerves are what type of fibers?
A-fibers
Unmyelinated nerves are what type of fibers?
C-fibers
pain and temperature fibers are what type of fibers?
Unmyelinated C-fibers
What are the two types of A-fibers?
Alpha, Beta
These fibers has to do with proprioception?
A-alpha fibers
These fibers has to do with discriminatory touch (hair receptors, vibration)?
A-beta fibers
There fibers has to do with temperature?
A-gamma fibers
These fibers has to do with pain?
A-delta fibers
The largest and fasted fibers you have are what type of fibers?
A-alpha
The type of pain you get when you hit your finger with a hammer and feel the pain instintaneously is what?
A-delta
The throbing pain you continue to have after you hit your thumb with a hammmer is what type of fibers?
Slow C fibers
There are two subtypes of pain fibers, what are they?
Fast pain
Slow pain
Instantaenous pain that makes your arm jerk back before you even realize you were burned is carried by what type of fiber?
A-delta fibers
Fast pain fibers are carried by?
A-delta
Slow pain fibers are carried by?
C-fibers
What fibers are the only unmyelinated sensory axons without myelin?
C-fibers
There fibers carry dull and aching pain, and it does not trigger withdrawal reflexes is what type fibers?
C-fibers
These fibers cross ofver from one side of the cord to the other side, or goes from onside of the CNS to the other side of the CNS is called?
Decussate
Most information from the somatic receptors when it gets to the spinal cord will cros over at some point, this crossing over is termed?
Decussate
Most input from somatic receptors on one side of the body will cross over to the opposite side of the CNS before it ascends to the thalamus, this is termed?
Decussate
From the thalamus, where does the somatic sensory information go?
The sensory information proceeds to the somatosensory (primary sensory cortex) cortex of the postcentral gyrus in the parietal lobe of the cerebrum.
At what region does sensory input become conscious perception?
Cortical region
A series of 3 neurons is needed to get the message from the body surface to the cortex, what are they?
First-orger neurons
Second-order neurons
Third-order neurons
which order neuron carries input from the skin to the CNS(into spinal cord)?
First-order neurons
In the ascending somatiosensory pathway, which "order" neuron crosses over (dessucates) to the opposite side of CNS and carries input up the spinal cord to the thalamus?
Second-order neurons
What order neuron relays information from the thalamus into the somatosensory cortex?
Third-order neurons
There are two key pathways that mediate conscious sensations, what are they?
Dorsal Column-Medial Lemniscal pathway,
Anterolateral spinothalamic pathways
Other names for Dorsal column-medial lemniscal pathways are?
dorsal-lemniscal or tract, dorsal column or tract, or posterior column
The anteriolateral spinothalamic pathway is comprised of what two pathways?
Lateral spinothalamic tracts,
Anterior or ventral spinothalamic tracts
Discriminative (detailed, fine) touch, proprioception (limb position/motion sense), and vibration is what pathway?
Dorsal column pathway
Pain, temperature, and gross touch is what pathway?
Spinothalamic pathway
The dorsal column-medial lemniscal (DCML) pathway axons synapse on what?
Ventral posterior nucleus (VPN) of hte thalamus
The Ventral Posterior neucleus (VPN) projects to the?
Primary somatosensory cortex or S1
The spinothalamic neurons also synapse where?
The ventral posterior neucleus (VPN, but in a different region, they also synapse on the small intralaminar neclei of the thalamus.
The bid difference between the two DCML and Spinothalamic pathways is their level of decussation. What is the level of decussation of both?
DCML -at the level of the medulla
Spinothalamic pathway at the spinal cord
The dorsal root axon come in carrying what fibers?
A-alpha, A-beta, A-delta
The Dorsal-Column Medial Lemniscal (DCML) pathway enters the spinal cord via?
The dorsal root ganglion
Fibers of the DCML that form the lower extremities (level T7 or below) ascend in the?
Fasiculus Gracilis
Fibers from the upper extremities (above the level of T7) ascend in the?
Fasiculus Cuneatis
The fibers of the DCML enter the ipsilateral dorsal column, and branch off, some become reflex pathway, and the remainder of the fibers ascend in what two tracts?
Fasiculus Gracilis, Fasiculus Cuneatis
Fibers of the Fasiculus gracilis, and Fasiculus cuneatis are what order neurons?
First-order neurons
The dorsolateral fasciculus is also called?
The tract of Lissauer
What makes up the dorsal columns ?
Fasciculus gracilis
Fasciculus cuneatus
The DCML first order neurons synapse onto second-order neurons where?
in the nucleus gracilis and nucleus cuneatis of the medulla
The second-order fivers of the DCML then decussate to ascend contra-laterally in the medial lemniscus and synapse with teh contra-lateral ?
Thalamus
The DCML third-order neurons are located in the ventral posterolateral nucleus of the thalamus, and project through to where?
The posterior limb of the internal capsule of the somatosensory cortex in the postcentral gyrus
This type of monitoring detects posterior (dorsal) cord ischemia (primarily gracilis or cuneatus tracts) or brain ischemia is called?
Sematosensory Evoked Potential (SSEP)
A lesion/damage of the DCML pathway results in los of ability to consciously perceive the position and movements on what side of the body?
Ipsilateral (same side) limb below the level of damage.
This level of CNS is a conduit for signals from the periphery of body to brain and vice versa?
Spinal Cord level
The presynaptic neuron does what?
Secretes the neurotransmitter
Is sending the information
The postsynaptic neuron does what?
Has the receptors
Is where the neurotransmitter acts
Neurons are similar to other cells how?
Surrounded by a cell membrane
Have a nucleus tha contains genes
Contain cytoplasm, mitochondria and other organells
Carry out basic cellular process such as protein synthesis and energy production
How do nuerons differ form other cells in the body?
Have specialized extensions called dendrites, and axons,
Communicate with each other through electrochemical process
Contain some specialized structures (synaposes) and chemicals (neurotransmitters)
The site of summation for incoming information is at the ?
Axon Hillock
Terminal buttons form the?
Presynaptic neuron of the synapse
Mitochondria is usually plentifyl in what region of the neuron?
Presynaptic terminal or (end bulb)
The presynaptic membranes contain voltage-gated calcium channels that cause?
Depolarization of presynaptic membrane by an action potential which opens Ca channels,
Influx of Ca induces release of neurotransmitter,
which results in fusion of synaptic vessel to membrane and release of transmiter by exocytosis
Transmitters that open sodium channels ______ the postsynaptic neuron.
Excite
Transmitters that open chloride channels ________ the postsynaptic neuron.
Inhibit
About 75% of the second messenger activators are transduced with __________ coupled receptors.
G-protein
G-protein activation initiates a cascade of events that leads to an increase in ________ which causes protein ______________ which leads to alterations in cellular activity.
cAMP
Phosphorylation
Acetylcholine, norepinephrine, dopamine, serotonin, GABA, glycine, glutamate, and NO are all considered?
Neurotransmitters
Endorphins, enkephalins, VIP are condisered?
Neuropeptides
There are two pathways of the The anterolateral (spinothalamic) pathways what are they?
Lateral spinothalamic tract
Anterior (ventral) spinothalamic tract
The lateral spinothalamic tract transmits signals for?
Pain and temperature
The anterior (ventral) spinothalamic tract transmits signals for?
Crude touch, tickle, pressure, itch
In the spinothalamic pathway, both tracts (lateral and anterior (ventral)) spinothalamic tracts enter where?
The dorsal gray horn and almost immeduately synapse with second order neurons.
In the spinothalamic pathway, the axon of the 2nd order neuron decussates hwere?
through the gray commissure and enters lateral or anterior tract, depending upon the modality being carried.
In the spinothalamic pathway, the 2nd order neuron passes thru the brain stem to connect with the 3rd order neuron where?
Thaamus
In the spinothalamic pathway, the 3rd order neuron synapses where?
Cortical neuron where perception of the modality occurs.
The lateral pinothalmic tract carry what type of impulses?
Pain, temperature sensations
The anterior spinothalmic tract carry what type of impulses?
Crude touch, pressure sensations
A protective mechamism of the body that cause individual to remove itself from a stimulus is?
Pain
There are two types of pain?
Fast pain - felf with 0.1 sec, sharp pain
Slow pain - last longer, throbbing or aching in nature
All pain receptors are?
Free nerve endings
There are multiple types pain stimuli, what are they?
Mechanical (stretch)
Thermal
Chemical (chemical mediators)
Chemical pain mediators are what?
Bradykinin, serotonin, histamine, potassium ions, acids, acetylcholine, proteolytic enzymes
Which substances enhance the sensitivity of pain?
Prostaglandins and Substance P
Pain that is elicited by mechanical and thermal stimuli is considered?
Fast pain
This pain can be elicited by all three types of stimuli (mechanical, thermal, chemical)?
Slow pain
Pain receptors do or do not adapt to the stimulus?
Do not
The rate of pain is most often caused by?
The rate of tissue damage
This chemical mediator causes the most pain and may be the single agent most responsible for causeing the tissue damage type of pain?
Bradykinin
Fast pain is transmitted by what type fibers?
A-delta, myelinated
Slow pain is transmitteed by what type of fibers?
Type-C unmyelinated
Fast pain fibers are transmitted in the?
Neospinothalamic tract
Slow pain fibers are transmitted in the?
Paleospinothalamic tract
The pathway for fast sharp pain is?
Fast and slow pathways are activated,
A-delta, and Type-C fibers enter dorsal spinal cord and divide and ether ascend or descend 1-3 segments in the Tract of Lossauer;
After leaving tract of lissauer, axons of A-delta fibers enter dorsal horm, and terminate in Rexed's lamin I & V.
2nd order neurons leaving Lamina I&V cross to contralateral lateral spinothalamic tract and ascend to the brain
The site of summation for incoming information is at the ?
Axon Hillock
Terminal buttons form the?
Presynaptic neuron of the synapse
Mitochondria is usually plentifyl in what region of the neuron?
Presynaptic terminal or (end bulb)
The presynaptic membranes contain voltage-gated calcium channels that cause?
Depolarization of presynaptic membrane by an action potential which opens Ca channels,
Influx of Ca induces release of neurotransmitter,
which results in fusion of synaptic vessel to membrane and release of transmiter by exocytosis
Transmitters that open sodium channels ______ the postsynaptic neuron.
Excite
What cause us to be able to compreshend quality of pain?
Cortex
What are the three major componets of the analgesia system used to modulate pain?
Periaqueductal Gray and Periventricular areas;
Raphe magnus nucleu;
Pain inhibitory complex in the dorsal horns of the spinal cord
The three major components of the analgesia system that modulates pain are what type of tracts?
Descending spinal cord tracts
In higher brain levels, the periventricular neclei of the hypothalamus, and the medual forebrain bundle can activate theperiaqueductal gray region and suppress pain by cause the release of what?
Endorphins and or enkephalins
Nerve fibers in the periventricular nucleus and the periaqueductal gray area secrete what?
Enkephalins at their nerve endings
Nerve fibers from the Raphe magnus secrete what at their nerve endings?
Serotinin
This causes the local neurons to secrete enkephalins?
Serotonin
Enkephalins are believed to cause both pre- and post-synaptic inhibition of what fibers where they synaps in the dorsal horn?
Type-C and A-delta fibers
Substance P is released from where?
Substantial Gelatinosa in the spinal cord.
Substance P is a neurotransmitter for what type pain fibers?
Type C pain fibers
What is the bodies way to take care of pain?
RElease less substance-P, causes fewer pain impulses to be sent up the ascending tract in the lateral spinothalamic tract.
When released, enkephalins decrease the release of what substance that inhibits pain perception?
Substance P
The descending dorsolateral tract does what to pain?
Modulates pain
IV Opioids produce analgesia in part by initiating action potentials where?
In the descending dorsolateral funiculus
There are two kinds of analgesia that occurs, what are they?
Supra-spinal anelgesia
Spinal anelgesia
Opioids act in the brain at what sites?
Limbic system, hypothalamus, and thalamus
Supraspinal analgesia is mediated by what?
Mu-1, Kappa, and delta receptors
The dominant receptor mediating supraspinal analgesia is?
Mu-1 receptor
The a patient responds to pain as "I feel pain, but I dont care", this is what type of alalgesia?
Supraspinal analgesia
Spinal analgesia is mediated primarily by?
Mu-2 receptors
Spinal alalgesia occurs when the number of pain impulses is decreased where?
Substantia gelatinosa
Spinal analgesia receptors are?
Mu-1, Mu-2, Kappa, and deltal receptors
The dominant receptor mediating spinal analgesia is what?
Mu-2 receptor
Enkephlin will work at the same opioid sites as?
Mu-2 receptors
Each spinal nerve innervates a segmental areas of skin designated as a?
Dermatome
A dermatome map is useful in determining what?
Level of spinal cord injury;
Level of sensory anesthesia produced by regional anestheia
How many dorsal nerve roots need or have to be interrupted to produce complete denervation of a dermatome?
3
What are the important dermatome landmarks?
Clavicle
Niples
Xiphoid
Umbilicus
Tibia
Perineum
C4
T4
T6
T10
L4-5
S2-5
Several "opiate-like" substances have been identified, and broken down into three large molecules, what are they?
Proopiomelanocortin; Proenkephalin; and Prodynorphin
The major opiate substances are?
B-endorphin, Met-enkephalin, Leu-enkephalin, Dynorphin
Enkephalins and Dynorphins are found where?
In the brain stem and spinal cord
The B-endorphins are found where?
Hypothalamus nad pituitary gland
Pain from an internal organ that is perceived to originate from a distant area of the skin is considered?
Referred pain
Causes of visceral pain are?
Ischemia
Chemical irritation
Spasm of a hollow viscus
Overdistension of a hollow viscus
Brain tissue is sensitive or insensitive to pain?
Insensitive
Inflammation of the meninges resulting in a severe headache is called?
Meningitis
This type of headache Results form abnormal vascular phenomenon?
Migraine
Things that can cause incracranial headaches are?
Menigitis, Migraine, Low CSF, Hangover