Unit 2 Synapes Flashcards
(66 cards)
what is the sequence of events at a synapse
1- neurotransmitter synthesis
2- ap and NT release
3 - NT binding and post synaptic effects
4 - NT detachment
5- NT removal or recycling
6 - feedback and regulation
neurotransmitter
chemical messengers that transmit signals between neurons
nitric oxide
chemical formula NO, is a gas released by many small local neurons
○ Poisonous, but many neurons release it when they are stimulated
○ Dilates vessels in highly active brain, increasing blood flow
what are the 6 types of neurotransmitters
amino acids, modified amino acid, monoamines, neuropeptides, purines, gases
amino acids
acids containing an amine group
Neurons synthesize nearly all neurotransmitters from amino acids
Catecholamines
compounds that contain a catechol and an amine group
Relationship among epinephrine, norepinephrine, and dopamine compounds
where are most NTs synthesized
presynaptic terminal
vesicles
tiny nearly spherical packets found in presynaptic terminal that store and release NTs
MAO (Monamine oxidase)
enzyme that converts catecholamines and serotonin into synaptically inactive chemicals MAOIs, prevents the transmitters to accumulate to harmful levels
Exocytosis
bursts of release of neurotransmitter from presynaptic neuron to synaptic cleft, caused by calcium entering terminal
synaptic cleft
the space between the presynaptic and postsynaptic neurons to the post synaptic membrane
what can the receptor do when a NT attaches to it? (1 of 2 things)
Ionotropic Effects or Metabotropic Effects
Ionotropic Effects
synaptic effects that depend on the rapid opening of some kind of gate in the
membrane, produce brief on/off effects when NTs bind (fast and short lasting)
Metabotropic effects
a sequence of metabolic reactions that produce slow and long-lasting effects at a synapse
what is the sequence of events that happens during metabotropic effects
NT binds –> receptor bends –> G protein detaches –> Result of a G protein is a second messenger
G protein
a protein coupled to guanosine triphosphate (GTP), an energy-storing molecule, part of metabotropic effects and results in a second messenger
neuropeptides
chains of amino acids (often referred to as neuromodulators)
hallucinogenic drigs
drugs that distort perception, such as lysergic acid diethylamide (LSD)
Chemically resemble serotonin, and attach to serotonin receptors
nicotine
a compound found in tobacco
opiates
drugs that are derived from, or chemically derived from, the opium poppy
auto receptors
a mechanism that prevents excess NT release, respond to the neurotransmitter they release, providing negative feedback to reduce further release, located on presynaptic terminal
reverse transmission
a mechanism that prevents excess NT release, where post synaptic neurons release chemicals like NO, that travel back to inhibit NT release
what are the reverse transmitters
nitric oxide, hydrogen ions, anandamide, 2-AG
2-AG
a reverse transmitter, chemical that binds to cannabinoid receptors