Neurotransmitters and Synaptic Transmission Flashcards
What are the two types of synapses?
Electrical and Chemical
Electrical Synapses
Gap Junction where electrical current flows directly from one cell to the next, smooth muscle and cardiac muscle
Chemical Synapses
Neurotransmitters are released in synapse (CNS)
What is the precursor for Acetylcholine?
Acetyl-CoA and Choline
What are the three terminals that an axon can synapse at?
axodendritic, axosomatic, axoaxonic
What aids in the exocytosis of neurotransmitters in vesicles?
SNARE proteins- that help dock vesicle to the membrane
What is one motor unit?
a motor neuron and the muscle fibers it innervates
What are the two main types of neurotransmitters and examples?
Small molecules (Ach, ATP, Serotonin, Dopamine, Epi, Norepi) Peptides (hormones and endorphins)
What is the precursor for GABA?
Glutamic acid
What is the precursor for serotonin?
Tryptophan
What are the precursors for epinephrine?
Tyrosine>dopa>dopamine>norepinephrine>epi
Where are hormones released from (2)?
Hypothalamus
Pituitary Gland
Where are the small molecule neurotransmitters made?
presynaptic axon terminal
Where are the peptides made?
Made in the cell body
What are the peptides transported down the axon with?
Microtubules
What are the three types of neurotransmitter receptors?
1- Ligand gated ion channels (ionotropic)
2- GPCR (metabotropic)
3- Enzyme linked receptors (TKR)
What do ionotropic receptors do when the NT binds?
Conformational change
What do the metabotropic receptors do when the NT binds?
Work by second messengers
Describe or sketch the Ach ionotropic and metabotropic receptor pathways.
Slide 20
Summarize the difference between long lasting (slow potentials) and short lasting (rapid potential) pathways
Slide 21
What are the three ways to terminate the NT?
breakdown (esterases)
reuptake (glial cells or presynaptic neuron)
diffusion (bloodstream)
What is the mechanism for SSRIs and cocaine?
They block the reuptake of NTs in the presynaptic neuron
What is the mechanism for Ecstasy and amphetamines?
They block the reuptake of NTs in the presynaptic neuron and increase the production/release of NT into the synapse
What is the mechanism for Nerve gases or insecticides?
they inhibit the enzymes that break down the NT (ex- block acetylcholinesterase and thus flood the synapse with Ach)
Explain how potentiation of synapses is a part of memory?
increased NT release
