Lecture 4- Transmission between neurons Flashcards
Describe transmission between neurons
-Neurons send messages via synaptic transmission -Neurotransmitters are released from one neuron and attach to another neuron -This initiates a reaction that results in postsynaptic potential
What is the synapse?
The junction between two neurons (terminal button + membrane)
What is the process of synaptic transmission?
Action potential > Ca channels open Ca2 enters > Vesicles fuse w/ membrane, pore opens > Release of NT (exocytosis) > NT diffuses, binds to postsynaptic membrane > Postsynaptic channels open > Ions flow, excitatory/inhibitory PSPs
What is neurotransmitter binding?
Neurotransmitter binds to binding site on post-synaptic membrane (lock/key).
-Postsynaptic potential depends on which ion channel (lock) is opened.
What is EPSP and IPSP?
EPSP = excitatory postsynaptic potential IPSP = inhibitory postsynaptic potential
What are the 2 types of receptors?
Ionotropic and Metabotropic receptors
What are inotropic receptors?
-Contains a binding site and ion channel.
This opens when a molecule attaches to a binding site.
What are the Metabotropic receptors?
-Contains a binding site, initiates a chain reaction that eventually opens ion channel. Requires energy. -PSPs slower than those produced by inotropic receptors
What are the 2 types of termination?
Reuptake
Enzymatic deactivation/degradation
What is reuptake?
Transmitter is taken back by the presynaptic terminal via transporter molecules.
What is Enzymatic deactivation/degradation?
Transmitter broken down by an enzyme.
In terms of neural integration, what is Excitatory and Inhibitory?
Excitatory- increases likelihood of neuron firing Inhibitory- decreases likelihood
What does inhibition of inhibitory neurons mean?
more likelihood of behavior
What is integration regarding neural integration?
Summation of PSPs in control of neuron firing
What is the difference between Inotropic and Metabotropic receptors in terms of methods?
Ionotropic - Direct method of opening channels
Metabotropic - Indirect methods of opening channel
Describe the GABA neurotransmitter?
-Most abundant inhibitory NT in the CNS
-Reduces chance of neuronal firing
Describe the Glutamate neurotransmitter
-Most abundant excitatory neuron in CNS
- Can bind to number of receptors
-Involved in learning and memory
Describe the Acetylcholine neurotransmitter
-Found in CNS + PNS
-Specifically at neuromuscular junctions as involved in muscular contraction
Describe the Dopamine and Serotonin neurotransmitters
Dopamine- Motor control, reward + addiction
Serotonin- Regulation of mood, eating, sleep
What is the most abundant inhibitory neurotransmitter?
GABA
What is the most abundant excitatory neuron?
Glutamate
What is neural integration?
-How to terminate postsynaptic potential -Can be done alone or in combination
