Term
| What are the major subdivisions of the CNS? |
|
Definition
|
|
Term
| What conduct impulses into the CNS? 2 names |
|
Definition
| afferent or sensory neurons |
|
|
Term
| What conduct impulses out of the CNS to muscles and organs? |
|
Definition
| efferent neurons or motor |
|
|
Term
| What are somatic motorneurons? |
|
Definition
| Reflex and voluntary control of skeletal muscle |
|
|
Term
| What are autonomic motor neurons? |
|
Definition
| involuntary effectors; smooth muscle, cardiac muscle, glands |
|
|
Term
| What two places will you find autonomic motor neurons? |
|
Definition
| sympathetic and parasympathetic |
|
|
Term
| What are interneurons and where are they located? (what is another name for them?) |
|
Definition
| associative neurons, they are in the CNS and serve integrative functions |
|
|
Term
| What is the basic functional unit of the CNS and PNS? |
|
Definition
|
|
Term
| What do neurons respond to? |
|
Definition
| physical and chemical stimuli |
|
|
Term
|
Definition
|
|
Term
|
Definition
| chemical mediators (neurotransmitter) |
|
|
Term
| What aids in perception of sensory stimuli, learning, and memory? |
|
Definition
|
|
Term
| In what system do neurons have limited capacity to divide? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Where does perception of sensory stimuli, learning and memory begin? |
|
Definition
|
|
Term
| What is the general direction of flow of information? |
|
Definition
| dendrites to axon terminus |
|
|
Term
| Where is the energy summed in a neuron? |
|
Definition
|
|
Term
| With the three types of organelle/protein transport within a neuron, what is the speed (fastest to slowest) 3 |
|
Definition
| Anterograde>retrograde>apoplasmic (anterograde and retrograde fall under "axonal") |
|
|
Term
| What is axoplasmic transport? |
|
Definition
| cytoplasmic streaming (like waves washing up on a beach) |
|
|
Term
| Is axoplasmic transport specific or nonspecific? |
|
Definition
|
|
Term
|
Definition
| transport (cell body to axon) is fast: moves toward the synapse (fastest) |
|
|
Term
|
Definition
| transport moves macromolecules and organelles back toward the nucleus (slower) |
|
|
Term
| What are characteristics of axonal transport? 3 points |
|
Definition
1) macromolecules, organelles, proteins originate in or near the cel body
2) transported down the axon on the cytoskeleton, using ATP, Ca, and motor proteins
3) Moves mitochondria, golgi vessels and synaptic proteins |
|
|
Term
|
Definition
| latent existence in axon terminus. When it is activated it moved to cell body and nucleus |
|
|
Term
| What type of transport is Herpres virus using when activated? |
|
Definition
|
|
Term
| How does rabies virus gain access to the nucleus? |
|
Definition
|
|
Term
| What does ganglia refer to? & where do you find them? |
|
Definition
| buncles of cell bodies (can be in CNS and PNS) |
|
|
Term
|
Definition
| bundles of axons, located outside of CNS |
|
|
Term
| A single nerve can contain _____ and _____ neurons |
|
Definition
|
|
Term
| What are support cells collectively referred to in the CNS? |
|
Definition
|
|
Term
| Compared to neurons, what displayed limited mitotic activity? |
|
Definition
|
|
Term
| What does the complexity of organisms seem to be related to? |
|
Definition
| more related to the ratio of support cells to neurons |
|
|
Term
| What are the types of support cells in the PNS? |
|
Definition
|
|
Term
| What are the support cells in the CNS? |
|
Definition
| Oligodendrocytes, microglia, astrocytes, ependymal cells |
|
|
Term
| Where are Schwann cells found? |
|
Definition
|
|
Term
| What is the structure of Schwann cells? |
|
Definition
| they are wrapped once around axons of the PNS |
|
|
Term
| What are the functions of the Schwann cells? |
|
Definition
| protection, insulation for improved conduction of action potentials |
|
|
Term
| One Schwann cell: _____ ______ |
|
Definition
|
|
Term
| What have myelin sheaths? |
|
Definition
| SOME axons in the PNS and CNS |
|
|
Term
| How is the myelin sheath formed in the PNS? |
|
Definition
| successive wrappings of Schwann cells around an axon like a roll of tape |
|
|
Term
| What are myelin sheaths formed by in the CNS? |
|
Definition
|
|
Term
| What happens to the cytoplasm of a Schwann cell as it wraps around the neuron? What is true about the portion that remains? |
|
Definition
| it is forced into the outlying cell body, the remaining around the cell body is the protein myelin |
|
|
Term
| Neurons larger than ___ are usually myrlinated |
|
Definition
|
|
Term
| Myelin= _____. It improves ___ |
|
Definition
| insulation, signal conductance |
|
|
Term
| What are the nodes of ranvier? |
|
Definition
| the gaps between the schwann cells (they wont overlap) |
|
|
Term
| What is responsible for myelination in the CNS? |
|
Definition
|
|
Term
| What are the differences between schwann cells and oligodendrocytes? |
|
Definition
| oligo wrap multiple neurons, the locations, oligo develop post natally, and oligo presence/absence determines gray/white matter |
|
|
Term
| One oligodendrocyte has cytoplasmic extensions that each wrap around an axon, ________ |
|
Definition
|
|
Term
| An individual oligodendrocyte can wrap around _____ axons |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Myelin sheath in the CNS is what color? |
|
Definition
|
|
Term
| areas of the CNS rich in axons are termed "__" |
|
Definition
|
|
Term
| Areas of the CNS with mostly cell bodies and dendrites are termed "__" |
|
Definition
|
|
Term
| What does multiple sclerosis do? |
|
Definition
| destroys myelination in the CNS |
|
|
Term
| What is the structure of an astrocyte? |
|
Definition
|
|
Term
| Where do you find end feet and what do they do? |
|
Definition
| Astrocytes, they surround microvessels and synapses. |
|
|
Term
| Endfeet are rich in what? |
|
Definition
|
|
Term
| What are the 4 functions of astrocytes? |
|
Definition
a) communication between neurons and the vasculature
b) Supplies energy (lactic acid)
c) K+spacial buffering
d) removal of neurotransmitters |
|
|
Term
|
Definition
| regulation of blood supply |
|
|
Term
| How do astrocytes remove neurotransmitters? |
|
Definition
| They take up glutamate, convert it to glutamine. Glutamine is released to neurons for synthesis of glutamate. |
|
|
Term
|
Definition
| a neurotransmitter (an agonist for signal receptors) |
|
|
Term
|
Definition
| a precursor for glutamate |
|
|
Term
| astrocytes _____ glutamate and ____ glutamine |
|
Definition
|
|
Term
| astrocytes signal to other glia through what? |
|
Definition
|
|
Term
| Astrocytes signal support from what 3 things? |
|
Definition
| cells, microvessels and neurons |
|
|
Term
| What is the best way to treat CNS trauma? What does this mean regarding astrocytes? |
|
Definition
| Improve the support cell function--you want to trigger astrocytes |
|
|
Term
| What are the 4 neural support cells? |
|
Definition
| microglia, oligodendrocytes, astrocytes, ependymal cells |
|
|
Term
| Microglia: why is the brain immune privileged? |
|
Definition
| BBB, brain remodeling, and the fact that the brian is 'protected' to prevent inflammation because brain isnt equipped to remodel |
|
|
Term
|
Definition
| astrocytes and endothelial cells |
|
|
Term
| What should you think of when you see microglia? |
|
Definition
|
|
Term
| Where do you find ependymal cells? |
|
Definition
|
|
Term
| What do ependymal cells do and where are they in the CNS? |
|
Definition
| lining ventricles in the brain, and they priduce/regulate cerebral spinal fluid |
|
|
Term
| What are ependymal cells associated with? |
|
Definition
|
|
Term
| Where do you find satellite cells? |
|
Definition
|
|
Term
| What do satellite cells do? |
|
Definition
| regulate chemical environment |
|
|
Term
| How do astrocytes regulate chemical environment? |
|
Definition
| See functions, just questioned differently |
|
|
Term
| Do CNS neurons regenerate spontaneously? |
|
Definition
|
|
Term
| What are the factors limiting spontaneous regeneration in the CNS? 3 |
|
Definition
1) inhibitory factors present in the CNS myelin
2) accumulation of proteoglycans associated with astroglial scarring
3) Difficulty in reforming numerous connections |
|
|
Term
| Can peripheral nerves regenerate? |
|
Definition
|
|
Term
| If a PNS neuron is severed, how is it fixed? |
|
Definition
| the distal portion of the axon is phagocytized by schwann cells and macrophages |
|
|
Term
| What do schwann cells form to guide the regenerating axon to its target? |
|
Definition
|
|
Term
| What factors help in PNS regeneration? what cells are they secreted by? |
|
Definition
| trophic factors: schwann cells and microglia |
|
|
Term
| Large peripheral nerves can be reconnected ____ |
|
Definition
|
|
Term
|
Definition
| molecules that promote growth and development |
|
|
Term
| Where do you find neurotrophins? |
|
Definition
|
|
Term
| What are examples of neurotrophins |
|
Definition
| Nerve growth factor, brain derived neurotrophic factor, neurotrophins 1-5 |
|
|
Term
| What is required in adults for nerve maintenance? |
|
Definition
|
|
Term
| What is important in nerve regeneration? |
|
Definition
|
|
Term
| What pathway do neurotrophins work though? |
|
Definition
| tyrosine kinase linked receptors: autophosphorilation |
|
|
Term
| What proteins help nerve development and function? |
|
Definition
|
|
Term
| How are neurotrophins available in children and adults? |
|
Definition
|
|
Term
| What is related to reduced plasticity in adults? |
|
Definition
|
|
Term
|
Definition
| The ability to correct damage |
|
|
Term
| What is the structure of the BBB |
|
Definition
| The brain capillaries do not have pores between endothelial cells |
|
|
Term
| What are brain endothelial cells joined together by? |
|
Definition
|
|
Term
| What may regulate permeability of endothelial cells? |
|
Definition
|
|
Term
| What type of molecules will cross the BBB |
|
Definition
|
|
Term
| Water soluble molecules require what to enter the CNS? |
|
Definition
| active/facilitated transport |
|
|
Term
| Parkinsons: What neurotransmitter is related to it? |
|
Definition
lacks dopamine-->less signal transduction
Use LDopa because it is a precursor for dopamine |
|
|
Term
| Neurons have an RMP of: which side is more negative? |
|
Definition
| -70: inside is more negative |
|
|
Term
| Neurons can alter their membrane potential in response to _____ |
|
Definition
|
|
Term
|
Definition
| altering the plasma membrane permeability to ions, through activation of channels |
|
|
Term
| What is associated with depolarization? |
|
Definition
| becomes more positive, Na+ enters the cell |
|
|
Term
| What is associated with hyperpolarization? |
|
Definition
| cell becomes more negative, with a leaving of K+ |
|
|
Term
| After a hyperpolarization/depolarization, a return to RMP is termed a |
|
Definition
|
|
Term
| What will the channel do with a depolarization? |
|
Definition
|
|
Term
| Changes in RMP are monitored by ___ and ____ |
|
Definition
|
|
Term
| After the cell is at resting potential, they will reach ____, which is threshold. At that point, ___ channels open until the cell reaches _____. Then the ____ channels close and ____ open and RMP returns to normal |
|
Definition
|
|
Term
| At what point to Na channels close and K channels open? |
|
Definition
|
|
Term
| How does the cell repolarize? |
|
Definition
|
|
Term
|
Definition
| the ability of a neuron to transmit an electrical signal |
|
|
Term
| Stimuli below threshold are transmitted for ____ mm of an axon |
|
Definition
|
|
Term
| Do axons have good cable properties? |
|
Definition
|
|
Term
| Why can't neurotransmission rely only on cable properties? |
|
Definition
| No neuron could be longer than 2 mm. |
|
|
Term
| How do we improve cable properties? |
|
Definition
|
|
Term
| Do axons regenerate charge as they move along? |
|
Definition
|
|
Term
| What do depolarizations above threshhold create? |
|
Definition
| an electrical signal strong enough to propagate as an action potential |
|
|
Term
| How are action potentials transmitted? |
|
Definition
| from one small segment of an axon to another |
|
|
Term
| Threshold depolarization is strong enough in one segment to do what to the next segment? |
|
Definition
| open voltage gated channels in the next one |
|
|
Term
| Small changes in action potentials are/are not propagated |
|
Definition
|
|
Term
| complete membrane depolarization is/is not propagated |
|
Definition
|
|
Term
| How will local/weak depolarizations react? |
|
Definition
| are small and don't reach threshold: so wont send at all |
|
|
Term
| What is a threshold depolarization? |
|
Definition
| cell has gone to +35 and causes adjacent membrane to depolarize and generate action potential |
|
|
Term
| What are the two major differences between local responses and action potentials? |
|
Definition
- action potential is a larger response and totally reverses the entire membrane potential
- action potential is propagated down the length of an action |
|
|
Term
| Are small changes in polarizations propagated down the length of an axon? |
|
Definition
|
|
Term
| What is the range of a localized response? |
|
Definition
|
|
Term
| What is the value of the amplitude once an action potential is generate? |
|
Definition
| it is always the same: the membrane is completely depolarized |
|
|
Term
| Strength of depolarization ___ change the amplitude of depolarization |
|
Definition
|
|
Term
| What happens when there is a stronger depolarization? |
|
Definition
| the number of action potentials increases |
|
|
Term
| action potentials are ____, not ______ modulated |
|
Definition
|
|
Term
| Why is the amplitude of depolarization all or none? |
|
Definition
| it either has the depolarization or it does not! |
|
|
Term
| How is stimulus intensity coded? |
|
Definition
| the frequency of action potentials. the number of action potentials is what matters. |
|
|
Term
| What are required in order for neurons to release neurotransmitters? |
|
Definition
|
|
Term
| Neurotransmitters will trigger the release of what? |
|
Definition
| bioactive molecules such as hormones and contraction of muscle |
|
|
Term
| What are non-threshold changes? |
|
Definition
| changed in RMP that don't in and of themselves reach threshold |
|
|
Term
| T/F the cell experiences stimulatory and inhibitory signals at the same time which are integrated at the axon hillock of neurons |
|
Definition
|
|
Term
| If the stimulatory signals exceed the inhibitory signals, what occurs? |
|
Definition
| an action potential can result, so the cell can effect a change by releasing bioactive molecules that can change RMP in effector organs |
|
|
Term
| What is an action potential? |
|
Definition
| complete membrane depolarization (switching charges) |
|
|
Term
| Once threshold is reached and an action potential is fired...what happens? |
|
Definition
| the cell will respond ( releasing neurotransmitter ) if the stimulus is sufficiently strong, more action potentials will be generated and the cell will release more neurotransmitter |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| for a given impulse, ____ of the axons may be stimulated |
|
Definition
|
|
Term
| as stimulus intensity increased, what happens to axon stimulation? |
|
Definition
| more axons are stimulated, each at an increased frequency. |
|
|
Term
| what is another way to increase response when the stimulus is "strong?" |
|
Definition
|
|
Term
| What is the idea behind 'recruitment'? |
|
Definition
| More neurons are stimulated (each with the same amplitude of action potential) but they can stimulate more muscle fibers so the ability to do work increases. |
|
|
Term
| If action potential frequency increases, the time between them _____ |
|
Definition
|
|
Term
| What is the absolute refractory period? |
|
Definition
| During an action potential spike, a neuron cannot respons to another stimulus |
|
|
Term
| What is the relative refractory period? |
|
Definition
| After the Na+ gates have closed and the K+ gates are open, a strong depolarization can produce a second action potential |
|
|
Term
| What is the principle ion movement during relative refractory periods? |
|
Definition
|
|
Term
| What is the principle ion movement during absolute refractory period? |
|
Definition
| Na moving in as well as K moving out |
|
|
Term
| What blocks voltage gated Na channels? |
|
Definition
|
|
Term
| What blocks Na+ channels? |
|
Definition
|
|
Term
| What is the principle ion movement during absolute refractory period? |
|
Definition
| Na moving in as well as K moving out |
|
|
Term
| What blocks voltage gated Na channels? |
|
Definition
|
|
Term
| What blocks Na+ channels? |
|
Definition
|
|
Term
| Where does the first action potential begin? (unmyelinated axon) |
|
Definition
| Axon hillock - Na enters the first segment of the axon, stimulating the cell |
|
|
Term
| What happens after Na enters the first segment of the unmyelinated axon? |
|
Definition
| Influx of Na and cable properties depolarize an adjacent 1-2 mm section of axonal membrane, that is still at the RMP of -70 |
|
|
Term
| What happens in unmyelinated axon after the adjacent segment gets depolarized? |
|
Definition
| The Na flows in and another action potential is fired. |
|
|
Term
| What happens in unmyelinated axon after the second action potential is fired? |
|
Definition
| Adjacent regions continue to fire action potentials down the length of the axon. Each axon potential is a stimulus for the next segment in the sequence |
|
|
Term
| Are action potentials conducted? |
|
Definition
| Not really, they are regenerated along the length of the axon. |
|
|
Term
| When will some 'conductance' occur in axons? |
|
Definition
|
|
Term
| What happens to the amplitude of an action potential as it moves down an axon? |
|
Definition
| It remains constant (threshold is reached and the cell gets to +30) |
|
|
Term
| What three things are true of action potentials? |
|
Definition
| they are all or none, they move, and they occur without decrement |
|
|
Term
| Saltitory conduction refers to |
|
Definition
|
|
Term
| Where does depolarization occur in saltitory conduction? |
|
Definition
| the 1-2 mm myelinated segment |
|
|
Term
| What is the Node in saltitory conduction? |
|
Definition
| it is depolarized to threshold. Na Channels open and action potential is generated, this leads to second depolarization |
|
|
Term
| In myelinated axons, where is the action potential generated? |
|
Definition
|
|
Term
| The fewer action potentials you have, the ___ it will move |
|
Definition
|
|
Term
| What 5 points are there about unmyelinated axons? |
|
Definition
1) Conducted without decrement
2) Action potentials occur over entire length of axon
3) rate is slow
4) short distance conduction
5) Increasing axon diameter increases rate of conduction |
|
|
Term
| What 4 points are there about myelinated axons? |
|
Definition
1) conducted without decrement
2) action potentials occur only at Nodes of Ranvier (saltitory conduction)
3) Long distance conduction
4) Insulating myelin makes conduction substantially faster - they can also have increased axon diameter |
|
|
Term
|
Definition
| a functional connection between a neuron and another cell |
|
|
Term
| What is the synapse in CNS? |
|
Definition
| Neuron to neuron interaction |
|
|
Term
| What is the synapse in PNS? |
|
Definition
| neuron to neuron/effector cell such as a muscle or gland |
|
|
Term
|
Definition
| synapse between a neuron and muscle |
|
|
Term
| What are the three examples of synapses occuring between different portions of neurons? |
|
Definition
| axodendritic, dendrodendritic, axosomatic |
|
|
Term
| What are the two types of synapses? |
|
Definition
|
|
Term
| electrical synapses defined |
|
Definition
| impulses flow uninterrupted from one cell to the next |
|
|
Term
| In electrical synapses, how are cells joined together? |
|
Definition
|
|
Term
| How far apart are membranes in electrical synapses? |
|
Definition
|
|
Term
| Are electrical synapses one/two way conduction of impulses? |
|
Definition
| two way (based on concentration gradients) |
|
|
Term
| What are two examples of electrical synapses? |
|
Definition
| cardiac muscle and astrocytes |
|
|
Term
| How do electrical impulses communicate? |
|
Definition
|
|
Term
| What is the primary thing passing in electrical synapses |
|
Definition
|
|
Term
|
Definition
| in electrical synapses, they help pass information along |
|
|
Term
| Electrical synapses do not use ____ or ____ |
|
Definition
|
|
Term
| Movement in an electrical synapse is limited by ___ and __________ |
|
Definition
| size and concentration gradients |
|
|
Term
|
Definition
| transmission across the majority of CNS synapses is one way through a release of chemical neurotransmitters |
|
|
Term
| Does the CNS have gap junctions? |
|
Definition
| yes, but not too many of them, & since they release neurotransmitters, they primarily act through chemical synapses. |
|
|
Term
| What are some chemical neurotransmitters? |
|
Definition
| GABA, glutamate, ACh, epinephrine, serotonin, dopamine |
|
|
Term
|
Definition
|
|
Term
| Post synaptic membranes contain ______ types of receptors |
|
Definition
|
|
Term
| Composition of neurons varies with |
|
Definition
| the type of neuron and neurotransmitter |
|
|
Term
| Activation of EPSPs causes |
|
Definition
|
|
Term
| Exitatory post synaptic potential changes the __ |
|
Definition
|
|
Term
| What ions are involved in EPSPs? |
|
Definition
|
|
Term
| EPSPs are _____ depolarizations that are ____ |
|
Definition
|
|
Term
|
Definition
| Inhibit action potentials |
|
|
Term
| T/F Some receptors on the post-synaptic membrane may be inhibitory |
|
Definition
|
|
Term
| What does activation of inhibitory post synaptic receptors causes a ____ or ___ |
|
Definition
| hyperpolarization or IPSP! |
|
|
Term
| IPSPs involve a decrease in _____, and increase in ____ or a decrease in _____ |
|
Definition
|
|
Term
| Signals (depolarizations) flow down the ____ |
|
Definition
|
|
Term
| Where are dendritic signals summed? |
|
Definition
| axon hillock- the decision to fire an action potential is made here |
|
|
Term
| What is a stimulus for an action potential? |
|
Definition
|
|
Term
| What is the stimulus for EPSP/IPSP? |
|
Definition
|
|
Term
| What is the initial effect of EPSP/IPSP? |
|
Definition
| Receptor-operated effects |
|
|
Term
| What is the conduction distance for EPSP/IPSP? |
|
Definition
|
|
Term
| What is the max depolarization for EPSP/IPSP? |
|
Definition
|
|
Term
| Are EPSP/IPSPs an all or none event? |
|
Definition
| No- EPSPs are summed, producing graded depolarization |
|
|
Term
| Is there a refractory period for EPSP/IPSPs? |
|
Definition
|
|
Term
| What are drug effects on EPSP/IPSP? |
|
Definition
| not inhibited by TTX, but by other receptor agonists |
|
|
Term
| Is there a threshold for EPSP/IPSPs? |
|
Definition
|
|
Term
| What is the location of EPSP/IPSPs? |
|
Definition
| Dendrites: processes information |
|
|
Term
| What is the initial effect of an action potential? |
|
Definition
|
|
Term
| What is the conduction distance of an action potential? |
|
Definition
|
|
Term
| What is the max depolarization of an action potential? |
|
Definition
|
|
Term
| is an action potential an all or none event? |
|
Definition
|
|
Term
| does an action potential have a refractory period? |
|
Definition
|
|
Term
| What drugs affect an action potential? |
|
Definition
|
|
Term
| is there a threshold for an action potential? |
|
Definition
|
|
Term
| What is the location of an action potential? |
|
Definition
| axon: it conducts information |
|
|
Term
| What are the types of chemical neurotransmitters? |
|
Definition
| acetylcholine, monoamines (norepinephrine, dopamine, serotonin) and glutamate/glycine/GABA |
|
|
Term
| How does acetylcholine affect CNS neurons? |
|
Definition
|
|
Term
| How does acetylcholine affect PNS? |
|
Definition
| excitatory in PNS somatic motor neurons |
|
|
Term
| Where can ACh be excitatory or inhibitory? |
|
Definition
| in the autonomic nervous system of the PNS: it depends on the organ involved |
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Term
|
Definition
|
|
Term
| What are the two types of Ach Receptors? |
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Definition
|
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Term
| Nicotinic ACh receptors work through what signal transduction pathway? Where do they predominate/where within that? |
|
Definition
| Receptor operated Channels. They predominate in the PNS at neuromuscular junction and in some areas of the CNS |
|
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Term
|
Definition
G protein linked receptor of the Gq or Gi.
Predominates in CNS |
|
|
Term
| where do muscarinic receptors predominate? |
|
Definition
|
|
Term
| Where do nicotinic receptors predominate? |
|
Definition
|
|
Term
| Where are nicotinic receptors found (neuron)? |
|
Definition
|
|
Term
| Where are nicotinic receptors found (muscle)? |
|
Definition
| neuromuscular junction - motor endplate |
|
|
Term
| What blocks teh interaction of ACh with its receptor? |
|
Definition
|
|
Term
| How do you turn off a nicotinic ACh receptor? |
|
Definition
| Acetylcholinesterase: it degrades ACh bound to receptors (proteolytic degradation) |
|
|
Term
| Activation of the Nicotinic ACh receptor produces what? |
|
Definition
| an EPSP or IPSP at synapses between 2 cholinergic receptors (in nuronal and neuromuscular synapses |
|
|
Term
| What are produced at the neuromuscular junction? |
|
Definition
| EPSPs (at the postsynaptic membrane of the muscle fiber or motor end plate) |
|
|
Term
| What is the neuromuscular EPSP called? |
|
Definition
|
|
Term
|
Definition
| depolarization open VOC in the muscle cell, causes action potential in muscle, contraction |
|
|
Term
| Nicotinic ACh receptor activation: Neuronal synapse (4) |
|
Definition
1) produces an EPSP
2) Acts at the post synaptic neuronal membrane
3) Elicits depolarization
4) signal is summed at the axon hillock, to determine if threshold for actoin potential is reached |
|
|
Term
| Nicotinic ACh receptor activation: Neuromuscular Synapse (4) |
|
Definition
1) Produces an EPSP (skeletal, not cardiac)
2) Acts at the motor end plate of skeletal muscle
3) Elicits an endplate potential
4) Signal produces depolarization of muscle membrane and contraction |
|
|
Term
| Will muscarinic Ach receptors directly affect the ion channel? |
|
Definition
|
|
Term
| What signal transduction pathway do muscarinic ACh receptors use? |
|
Definition
| G protein coupled (Gq and Gi) |
|
|
Term
| Effects of the muscarinic ACh receptors are tissue and organ ____ |
|
Definition
|
|
Term
|
Definition
| Bgamma subunits activate K+ channel - important in neuronal inhibition of the heart |
|
|
Term
| How do the Gamma cells affect the cardiac muscle in M1 muscarinic receptors? |
|
Definition
| gamma binds to K+ channels in pacemaker cells, K+ moves out, cells are hyperpolarized, producing an IPSP which slows heart rate |
|
|
Term
| Chemical neurotransmitters: monoamines |
|
Definition
| norepinephrine, dopamine, serotonin |
|
|
Term
| What are the catecholamines and what are they derived from? |
|
Definition
| norepinephrine and dopamine - they are derived from tyrosine |
|
|
Term
| What is serotonin derived from? |
|
Definition
|
|
Term
| Why is epinephrine not a neurotransmitter? |
|
Definition
| it is a hormone that is released into the blood. |
|
|
Term
| Do monoamines directly control ion channels? |
|
Definition
|
|
Term
| How do monoamines affect the membrane? |
|
Definition
| through G proteins: primarily coupled to activation or inhibition of adenylate cyclase: Gi or Gq or Gs |
|
|
Term
| Monoamine neurotransmitters influence ___ and ____ |
|
Definition
|
|
Term
| Norepinephrine neurotransmission picture |
|
Definition
|
|
Term
| How are monoamine neurotransmitters terminated? (3) |
|
Definition
1) reuptake of monoamines into presynaptic nerve terminals
2) Enzymatic degradation by monoamine oxidase
3) Enzymatic degradation of catecholamines by catechol-O-methyltransferase |
|
|
Term
| Will serotonin be affected by catechol-O-methyltransferase? |
|
Definition
| No, it is not a catecholamine |
|
|
Term
| What are monoamine oxidase inhibitors? |
|
Definition
| drugs that block the enzyme monoamine oxidase |
|
|
Term
|
Definition
| block degradation of catecholamines and serotonin --> increase signal transduction |
|
|
Term
| What are MAOs used in treating? |
|
Definition
| clinical depression (suggests that a decrease in monoamine activity may contribute to this disorder) and Parkinsons |
|
|
Term
| There are many serotonergic neurons in areas of the _____ |
|
Definition
|
|
Term
| What foods increase serotonergic neurotransmission? |
|
Definition
| tryptophan-rich food: milk, turkey |
|
|
Term
| physiological functions of serotonin |
|
Definition
| regulation of mood, behavior, appetite, and cerebral circulation; depression |
|
|
Term
|
Definition
|
|
Term
| What do serotonin re-uptake inhibitors block? |
|
Definition
| the termination of serotonin action (by reuptake) at the presynaptic nerve terminals |
|
|
Term
| What is the effect of serotonin re-uptake inhibitors? |
|
Definition
| increase the amount of time serotonin is present |
|
|
Term
| Dopaminergic neurons are concentrated in the _____ |
|
Definition
|
|
Term
| What are the two divisions of dopanime |
|
Definition
| nigrostriatal and mesolimbic |
|
|
Term
| Where are nigrostriatal nerve pathways located? |
|
Definition
| (dopaminergic neuron subtype) the cerebrum: they are involved in skeletal muscle movement and coordination |
|
|
Term
| Where are mesolimbic nerve pathways located? |
|
Definition
(dopaminergic neuron subtype) the midbrain and forebrain (part of the limbic system). dopamine signal released by these is associated with behavior/reward/effects.
- addictive drugs activate the mesolimbic dopaminergic system |
|
|
Term
| What is parkinson's characterized by? |
|
Definition
| muscle tremors/rigidity, impairment of movement, speech difficulities |
|
|
Term
| What is Parkinson's caused by? |
|
Definition
| degeneration of dopaminergic neurons of the nigrostiatal system ( though free radical generation from overactive microglia) |
|
|
Term
| How do you treat parkinson's? |
|
Definition
| L-Dopa (increases the amount of dopamine available) and MAO inhibitors (increase the amount of time dopamine is available) |
|
|
Term
| What is the potential benefit of microglia? |
|
Definition
|
|
Term
| What are excitatory neurotransmitters? |
|
Definition
| Stimulatory in CNS: glutamate and Aspartic acid. Produce EPSPs in the brain |
|
|
Term
| Inhibitory neurotransmitters |
|
Definition
| Inhibitory in CNS: Glycine and Gamma-aminobutyric acid (GABA). Produced IPSPs in the brain. |
|
|
Term
| What is the major excitatory neurotransmitter in the brain? |
|
Definition
|
|
Term
| What are the two subdivisions of glutamate receptors? |
|
Definition
| ionotripic and metabotropic |
|
|
Term
| What do ionotropic receptors do? |
|
Definition
| (glutamate receptors) regulate post-synaptic ion channels: primarily in neurons, some in astrocytes |
|
|
Term
| What do metabotropic receptors do? |
|
Definition
| (glutamate receptors) regulate G protein linked signaling pathways. Neurons and astrocytes |
|
|
Term
| What are bound by glutamate? |
|
Definition
| ionotropic and metabotropic receptors |
|
|
Term
| Ionotropic glutamate receptors |
|
Definition
|
|
Term
|
Definition
| an ionotropic receptor: Abundant in the brain, regulates postsynaptic Ca2+ channels |
|
|
Term
| What is an AMPA receptor? |
|
Definition
| ionotropic glutamate receptor: abudant in the spinal cord: regulates a post synaptic Na+ channel |
|
|
Term
| What is a neurotransmitter that binds to VOC or ACh? |
|
Definition
|
|
Term
| NMDA receptor activation picture |
|
Definition
|
|
Term
| What are the three steps in NMDA receptor activation? |
|
Definition
1) glycine or D-serine binding
2) Mg Leaving
3) binding of glutamate |
|
|
Term
| Metabotropic glutamate receptors link to what G proteins? |
|
Definition
|
|
Term
| What to metabotropic glutamate receptors regulate? |
|
Definition
| NMDA and AMPA receptors: maybe through kinase activation and phosphorylation of ion channels |
|
|
Term
| Where is calcium stored when metabotropic glutamate receptors? |
|
Definition
| dendritic postsynaptic spines |
|
|
Term
| What are metabotropic glutamate receptors critical to? |
|
Definition
|
|
Term
| What do inhibitory neurotransmitters produce? |
|
Definition
| an IPSP in postsynaptic dendrites |
|
|
Term
| What are two examples of inhibitory neurotransmitters? |
|
Definition
|
|
Term
| What is glycine important in controlling? |
|
Definition
| skeletal muscle movements |
|
|
Term
| How does glycine fit in the idea of flexing a muscle? |
|
Definition
| Motor neurons that counter the flexing are inhibited by IPSPs GENERATED BY glycine. |
|
|
Term
|
Definition
|
|
Term
| Glycine is the ____ muscle for muscle relaxation |
|
Definition
|
|
Term
| What causes the antagonist muscle to relax when one muscle contracts? |
|
Definition
| glycine binding (spinal cord) through Cl coming into the cell, it becomes hyperpolarized, and inhibited |
|
|
Term
| What is the most prevalent neurotransmitter in the brain? |
|
Definition
|
|
Term
| ___% of all brain neurons use GABA as _____ |
|
Definition
|
|
Term
| What does GABA do to neurons in the brain? |
|
Definition
| hyperpolarize by opening postsynaptic Cl- channels |
|
|
Term
| Where is GABA important? (specifically) |
|
Definition
| in the cerebellum, it works with mediation of motor functions |
|
|
Term
| What is Huntington's Chorea |
|
Definition
| uncontrolled movements due to deficiency of GABA secreting neurons (muscles contracting when you shouldn't by preventing it from NOT contracting) |
|
|
Term
| What is long term potentiation? |
|
Definition
Synapses stimulated with high frequencies exhibit increased post synaptic excitability
(BOOK: the improved efficacy of synaptic transmission |
|
|
Term
| How does LTP develop? (3) |
|
Definition
1) change in phosphorylation state
2) change in neuronal lipid membrane structure (dendritic spines, alterations in receptor expression, NMDA, AMPA)
3) Alterations in intracellular calcium stores in the ER, particularly in the dendrites
4) Alteration in the level of gene transcription. |
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