-
what causes the vesicles to move to the presynaptic membrane?
influx of Ca2+
-
what does block calciums lead to?
less NT fired
-
What happens when experimentaly lowering the concentrations of Ca2 around the terminal?
reduces amount of NT released
-
Who discovered NT?
Otto Loewi
-
WHta was Loewi discovery name?
Vagusstoff
-
In what form do vesiscle release NT?
exocytosis
-
Receptor
proteins in the membrane of post-synaptic cell that NT molecules bind to them
-
Receptors will only...
bind to specific NTs
-
3 types of receptors
-autoreceptor
-ionotropic
-metabotropic
-
overview of autoreceptors
- self-regulation
-they are positioned on the pre-synapic cleft
- when NT is released from Presynaptic, it binds to its autoreceptor cauing inhibation or stimulation of additional release
-
overview of Ionotropic receptors
-when NT binds to these receptors, channel opens
-can quickly depolarize or hyperpolarize the resting membrane
-
Metabotropic receptors
-more prevalent than iontropic
- -when NT bind to them cascade of intracellular events occur.
- *G-protein that is attached to it, is relased and acts on other elements
-
2 ways of stopping neurotransmission
-reuptake and enzymatic degradation
-
Reuptake
process is very rapid, once released, the NT are transported back into the pre-synaptic cell
-
Enzymatic degradation
enzymes can interact with certain NTs. When they do, enzymes destroy NTs form from preventing them from going to a receptor.
-
Enzymes
proteins that either stimulate or inhibit biochemical reactions without being effected by them
-
metabolites
- broken down bits of NTs
-can be taken back into the pre-synaptic membrane for synthesis .
-
four types of small NTs
-amino acids
-monoamines
-soluble gases
-acetylcholine
-
Amino acids
-glutamate
-aspartate
-glycine
-gamma-aminobutyric (GABA)
*these NTs are fashioned out of molecules from our diet
-
Amino acids- Glutamate
most prevalent excitatory NT in the mamalian central nervous system
-
Amino Acids- GABA
most prevalent inhibitory NT in the mamalian central nervous system
-
where do amino acids come from?
from foods that we eat
-
Nt- small molecules- Monoamines
-made from just one single amino acid
-less targeted than amino acid transmitters, they are relased more diffusely throughout the brain
-
Nt- small molecules- types of Monoamines
-dopamine
-norepinephrine
- -epinephrine
- * all 3 synthesized from Tyrosine
- -serotonin
- * synthesized from trytophan= lot of tryptophan in trukey
-
Nt- small molecules- 2 types of Soluble gases
-nitric oxide and carbon monoxide
-
Nt- small molecules- SOluble gases
-they are produced in cytoplam then diffused out of cell
- they enter post-synaptic cell and trigger second messenger cascades
-
Nt- small molecules- Axetylcholine
it is a NT released by neurons on to muscles
-
NT- Large peptides
-far too many to list
-plays role in lots of aspects of behavior such as feeding, drinking, and sex
-
Agonist
mimic effects of an endogenous NT by binding to its receptor and causing the same response
-
Antagonist
blocks the effects of an endogenous NT by binding to its receptor and preventing any NT from binding
-
what NT does Benzines mimic?
agnoist, GABA
|
|
