Neuro L.2 Main Concepts Flashcards
What is an axoaxonic synapse?
An axon of the presynaptic neuron forms a connection with the axon of the postsynaptic neuron, leading to presynaptic inhibition or facilitation.
What is an axosomatic synapse?
An axon of the presynaptic neuron forms a connection with the soma of the postsynaptic neuron, which is closer to the axon hillock.
What is an axodendritic synapse?
An axon of the presynaptic neuron forms a connection with the dendrite of the postsynaptic neuron, allowing for excitatory or inhibitory signaling.
This is the most common type of synapse.
What occurs during synaptic transmission?
When a receptor is stimulated, a local potential (small, graded potential) occurs, followed by the arrival of an action potential at the axon terminal.
What happens during depolarization in synaptic transmission?
Voltage-gated Ca channels open, allowing Ca to enter the presynaptic neuron.
What role does calcium play in synaptic transmission?
Calcium signals neurotransmitter vesicles to fuse with the presynaptic membrane and release neurotransmitters into the synaptic cleft via exocytosis.
What is an excitatory postsynaptic potential?
A local depolarization that allows Na/Ca to enter the cell.
What is an inhibitory postsynaptic potential?
A local repolarization that allows K/Cl to exit the cell.
What is acetylcholine (Ach)?
An excitatory neurotransmitter in the neuromuscular junction (NMJ) that causes muscle contractions and is involved in the autonomic nervous system’s parasympathetic functions.
What is myasthenia gravis?
A condition characterized by damage to Ach receptors.
What is glutamate?
The primary excitatory neurotransmitter.
What is GABA?
The primary inhibitory neurotransmitter.
What is dopamine?
A neurotransmitter that can be excitatory or inhibitory, produced in the substantia nigra.
What conditions are associated with dopamine?
Parkinson’s disease, schizophrenia, and ADHD.
What is norepinephrine?
A neurotransmitter associated with the fight or flight response, produced by the diencephalon and released by adrenal glands.
What are the effects of excessive norepinephrine?
It can lead to PTSD.
What are the effects of low norepinephrine?
It can lead to depression and sleep issues.
What is serotonin?
A neurotransmitter involved in mood, pain, perception, arousal, and motor activity.
What are the effects of high serotonin levels?
It can lead to increased alertness.
What are the effects of low serotonin levels?
It can lead to REM sleep issues and depression.
What is Lambert-Eaton Syndrome?
A condition characterized by damage to calcium channels, leading to muscle weakness.
