U6.2 NEUROTRANSMITTERS Flashcards
Drug selectivity is based on the fact that different pathways use different transmitters, a primary goal of neuroscience has been to identify the neurotransmitters in CNS pathways
Central Neurotransmitters
Criteria for Transmitter Status
Present in higher concentration in the synaptic area than in other areas
Localization
Criteria for Transmitter Status
Released by electrical or chemical stimulation via a
calcium-dependent mechanism
Criteria for Transmitter Status
Produce the same sort of postsynaptic response that is seen with physiologic activation of the synapse
Synaptic mimicry
Chemicals accepted as NTAs in the CNS
- 5% of neurons have receptors for ___
- G protein-coupled muscarinic M1 receptors
Acetylcholine (Ach)
Chemicals accepted as NTAs in the CNS
- ↓ slows excitation
- ↓ decreases permeability to potassium
Acetylcholine (Ach)
Chemicals accepted as NTAs in the CNS
Inhibitory actions at synapses in specific neuronal systems
Dopamine
Chemicals accepted as NTAs in the CNS
G protein-coupled activation of K+ channels
Dopamine
Chemicals accepted as NTAs in the CNS
D2 receptor is the main dopamine subtype
Dopamine
Chemicals accepted as NTAs in the CNS
↑ increases cAMP
Dopamine
Chemicals accepted as NTAs in the CNS + Effect
Activation of α1 and β1 receptors
Norepinephrine, Excitatory
Chemicals accepted as NTAs in the CNS + Effect
↓ decreases K+ conductance
Norepinephrine, Excitatory
Chemicals accepted as NTAs in the CNS
Activation of α2 and β2 receptors
Norepinephrine, Inhibitory
Chemicals accepted as NTAs in the CNS
↑ increases K+ conductance
Norepinephrine, Inhibitory
Chemicals accepted as NTAs in the CNS
Multiple 5 hydroxytryptamine (5-HT) receptor subtypes
Serotonin
Chemicals accepted as NTAs in the CNS
Metabotropic
Serotonin
Chemicals accepted as NTAs in the CNS
Inhibitory at many CNS sites
Serotonin
Chemicals accepted as NTAs in the CNS
Excitatory depending on the receptor subtype activated
Serotonin
Chemicals accepted as NTAs in the CNS
Excitatory for most neurons
Glutamic Acid
Chemicals accepted as NTAs in the CNS
N-methyl-D-aspartate (NMDA) receptor
Glutamic Acid