Transcript lectSides09.ppt

Topics
• Presynaptic: transmitters
– general considerations
• criteria, types
– small molecules
• synthesis, location
– peptides
• roles, synthesis from precursors
– co-existence
Topics
• Postsynaptic: second messengers
– access
• 7 transmembrane domain receptors, G proteins
– types
• cAMP, AA, DAG, IP3
– protein kinases
– truncating pathway
– utility
motor neur.  skel. mus.
CH3-C-O-CH2-CH2-N+-(CH3)3 + CoA ANS, esp. parasympath.
n. basalis of Meynert
acetylcholine
presynaptic modulator
O
CAT
acetyl CoA + choline
tyrosine + O2
TH
L-DOPA
AAAD
HOHO-
-CH2-CH2-NH2
substan. nigra  caudate n.
midbrain  limbic system
dopamine
dopamine
HOHO-
DBH
OH
-CH-CH2-NH2
sympathetic endings
locus coeruleus
myasthenia gravis
Alzheimer’s
Parkinson’s
drug addiction
schizophrenia
depression
norepinephrine
norepinephrine
PNMT
HOHO-
OH
-CH-CH2-NH-CH3
adrenal medulla
(neurohormone)
epinephrine
tryptophan + O2
TrH
5-HTP
AAAD
-CH2-CH2-NH2
N
H
glycine
GAD
depression
major excitatory transmitter
in brain
stroke
major inhibitory transmitter
in brain
epilepsy
serotonin
glutamate
glutamate
raphé n.
gamma-amino butyric acid (GABA)
major inhibitory transmitter
in spinal cord
Principles, Table 15-3
Principles, Fig. 15-2
Principles, Fig. 13-2
Principles, pg. 236
Principles, Fig. 13-6
Utility of second messengers
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•
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lengthening of signal
amplification of signal
divergence to several targets
convergence to single target
spatial spreading of signal
regulation of gene transcription