Action Potential
What is the polarity of the extracellular environment? intracellular environment?
Extracellular: positive (Na+, Cl-)
Intracellular: negative (K+, Proteins)
What are the two types of cells in the nervous system?
Neurons and Glia
Name the three classes of neurochemicals
Small molecules (amino acids, amines)
Neuropeptides
Gasotransmitters
What is the main inhibitory neurochemical?
GABA
What is the most permeable ion at resting potential?
Potassium
What ion exits cells during depolarization?
Potassium
Which two types of glia cells are used for myelination and where are they located (CNS or PNS)?
Oligondendrocytes (CNS)
Schwann cells (PNS)
What are the functions of Acetylcholine?
Movement
Autonomic function
Learning and Memory
What is the main excitatory neurochemical? What does excess activity cause?
Glutamate
excitotoxity
What channels/pumps help maintain resting potential?
Na+/K+ pump
leaky K+ channels
leaky Na+ channels
What channel opens once threshold is reached?
Sodium channels
What are the main components of the neuron (from input to output)?
Dendrites
Soma
Axon Hillock
Axon
Axon terminal
What are the functions of Dopamine?
Movement
Reinforcement
Planning
What are drugs that enhance the activity of neurochemicals? Name one way they can accomplish this.
Agonist
mimic neurochemical
increase production of neurochemical components
Block reuptake
inhibit enzyme that breaks neurochemical down
What are neurochemicals held in?
What channel closes once action potential is reached? What channel closes at the undershoot?
Sodium channels
Potassium channels
What is the most common type of glia?
Astrocyte
Name the functions of Norepinephrine
Arousal and vigilance
Mood
What are drugs that reduce the activity of neurochemicals? Name one way they can accomplish this.
Antagonist
Block receptor
Break down at synapse
promote reuptake
Where are voltage gated channels? Where are ligand gated channels?
Voltage- at axon
Ligand- synapse
Name the stages of the action potential and their voltage ranges.
Resting potential (-70 mV)
Threshold (-55 mV)
Depolarization (-55 to 40 mV)
Action potential (40 mV)
Repolarization (40 to -90 mV)
Hyperpolarization (-90 mV)
Name the five types of glia cells and where they are located.
Astrocyte: CNS
Ependymal Cells: lining of ventricles and central canal
Oligondendrocytes: CNS
Schwann Cells: PNS
Microglia: CNS
Name the functions of serotonin and the location of highest concentration.
Sleep, appetite, mood, aggression, social rank
Ralphe Nucleus
What do MAOIs and SSRIs do?
Monoamine oxidase inhibitors block action of MAO.
Selective serotonin reuptake inhibitors block reuptake of serotonin
Why are myelinated cells faster?
The signal propagates at nodes of Ranvier, while unmyelinated cells have to propagate at each successive axonal segment