Neurotransmitters Flashcards
What are the two types of synapse?
electrical and chemical
What are electrical synapses?
two neurons connected by a gap junction that allow electrical current to flow directly from one cell to the other
What are chemical synapses?
release neurotransmitters from presynaptic membrane and bind to receptors on post synaptic membrane
What do neurotransmitters trigger?
EPSP, IPSP, or modulate the post synaptic cell
What allows the voltage gated ion channels to open?
change in membrane potential
What helps to dock the vesicles and allow membranes to fuse of pre and post synaptic neurons?
SNARE proteins in the SV and plasma membrane
What does synaptotagmin activate?
synaptobrevin
What does synaptobrevin activate?
SNAP-25 and syntaxin
What does botulinum toxin do?
prevent calcium release for muscle contraction
-do not allow the SNARE proteins to be activated
What are excitatory NT?
-glutamate
-aspartate
-nitric oxide
What are inhibitory NT?
-glycine
-GABA
-serotonin
-dopamine
What NT are both excitatory and inhibitory?
acetylcholine and norepinephrine
What ions have a higher concentration outside the cell?
-Na
-Ca
-Cl
What ions have a higher concentration inside the cell?
-K
-Mg
What is the resting membrane potential?
-65 mV
What do excitatory NTs do?
open cation channels for Na and Ca
What do inhibitory NTs do?
open Cl channels
What is a graded potential?
action potentials that must move down the axon to the hillock
-loses some of the signal is it moves
What is an action potential?
when the membrane potential reaches the threshold and an all or nothing response occurs
What allows action potentials to only flow one way down the axon?
the Na channels have an inactivation gate that do not allow them to be open again until the resting membrane potential is back
How is serotonin created?
-tryptophan -> 5-hydrotryptophan -> serotonin
How is dopamine created?
tyrosin -> DOPA -> dopamine
How is norepinephrine made?
tyrosin -> DOPA -> dopamine-> norepinephrine
How is epinephrine made?
tyrosin -> DOPA -> dopamine-> norepinephrine-> epinephrine
