Neurotransmitters of Anesthesia Flashcards
NE
primary transmitter released from postganglionic sympathetic neurons
NE location
synthesized in nerve terminal- released into synapse to bind with alpha or beta receptors on postsynaptic membrane
NE removed by
reuptake or metabolized in the presynaptic terminal by MAO and COMT
NE metabolites
DOMA, NMN, MOPEG, VMA (vannillylmandelic acid)
Epinephrine synthesized
from NE by action of phenylethanolamine-N-methyltransferase
Epinephrine secreted
from adrenal medulla
Where is dopamine?
prominent in midbrain neurons
Dopamine released
from hypothalamus
What does dopamine do?
inhibits prolactin secretion
Dopamine metabolized by
MAO and COMT
D1 receptors
activate adenylate cyclase via Gs protein
D2 receptors
inhibit adenylate cyclase via Gi protein
Parkinson’s
degeneration of dopaminergic neurons that use D2 receptors
Where is serotonin?
present in high concentrations in brain stem
serotonin formed from
tryptophan
Serotonin converted to
melatonin in pineal gland
Histamine is formed
from histidine
Histamine is present in
neurons of hypothalamus
H1 receptors
in smooth muscle, endothelium, brain
-postreceptor increases IP3, DAG
H2 receptors
in gastric mucosa, cardiac muscle, mast cells, brain
-postreceptor increases cAMP
Glutamate
most prevalent excitatory NT in brain
GABA
major inhibitory NT
GABA synthesized from
glutamate by glutamate decarboxylase
GABAa
increase Cl- conductance- site of action of benzo and barbiturates
GABAb
increases K conductance
glycine
inhibitory transmitter in SC an brainstem
Glycine increase ? conductance
Chloride
Nitric Oxide
short acting inhibitory NT in GI, BV, CNS
NO synthesized in
presynaptic nerve terminals (NO synthase converts arginine to citrulline and NO)
