Lecture 4 Flashcards
One to One Syapses
one presynaptic to one postsynaptic
One to Many Synapses
one presynaptic to 1+ postsynaptic
motorneurons in spinal cord
amplify signal
Many to One Synapses
1+ presynaptic to 1 postsynaptic
allows for integration of many signals
Synaptic Transmission
neurotransmitter binds, changes post synaptic membrane potential
Excitatory Post Synaptic Potentials
depolarize cell towards threshold
Na channels open
Glutamate, Ach
Inhibitory Post Synaptic Potentials
hyperpolarize cell away from threshold
Cl channels open
GABA, glycine
Temporal Summation
time between synapses
Spatial Summation
multiple inputs at the same time
Neurotransmitter
made and released by pre-synaptic cell
Acetylcholine
made from acetate and choline
stored in vesicles
released in response to Ca2+ influx
broken down by acetylcholine esterase
Biogenic Amines
Broken down by MAO, COMT
determines amount of NT released
tryptophan (serotonin and melatonin) and histidine (histamine)
Amino Acids
Gaba, Glutamate, glycine
Gaseous Transmitters
cell permeant gasses (NO) that can act on postsynaptic cells
Neuropeptides
larger molecules like ADH of Oxytocin
neuromodulators and neurohormones
Neuromodulators
act on presynaptic cell to affect amount of NT release
Neurohormones
made by neurons and released into bloodstream to have effects
Purines
released with NT to augment effect
Ionotropic Receptors
receptor is ion channel
nicotinic receptor is primarily Na channels, GABA is Cl channels
fast to alter ionic flux
Metabotropic Receptors
coupled to G protein
binding of ligand activates protein to make 2nd messenger (IP3, cAMP), which interacts with ion channels and activate kinases
Receptor Tyrosine Kinase
RTK
Growth factor signaling
starts kinase cascade to change transcription
Receptor Tyrosine Phospatase
RTP
Growth Factor Signaling
Gs
stim adenylate cyclase- increase cAMP
Gi
Inhibits adenylate cyclase
decrease cAMP
Phosphodiesterase
PDE
degrades cAMP
Gq
activates phospholipase C to make IP3 and DAG
IP3
open calcium channels on intracellular stores
DAG
activate a kinase cascade through PKC
B1 location
heart
B2 location
smooth muscle
Alpha Adrenergic
respond to NE and Epi
a1- Gq
a2- Gi
Muscarinic Receptors types
respond to Ach
Gq- M1, M3, M5
Gi- M2, M4
Guanalyl Cyclase
makes cGMP
non-receptor can be activated by NO
2nd messenger in phototransduction pathway
broken down by PDE
