Page 96 - Color_Atlas_of_Physiology_5th_Ed._-_A._Despopoulos_2003

A. Neurotransmission in autonomic ganglia
Preganglionic
Presynaptic AP neuron
ACh
Ca 2+
Cholinergic
N N -receptor Peptide as a
co-transmitter
Cholinergic Peptide
M 1 -receptor receptor Acetylcholine and Cholinergic Transmission
G q protein PIP
K + Postganglionic
Phospholipase C β neuron
2+
Na + (Ca )
IP 3 DAG [Ca] i
20ms Early EPSP 2s Late EPSP Peptidergic EPSP or IPSP 60s
Plate 3.4
mV mV mV

Postsynaptic action potentials

B. Cholinergic transmission in the heart
Presynaptic AP ACh Postganglionic
parasympathetic
Ca 2+ neuron
Choline
Cholinergic
M-autoreceptor Acetate
Acetylcholine
Cholinergic esterase
+
M 2 -receptor K channel
Adenylyl cyclase G i protein G i protein
opens
Sinus node
ATP K + or AV node cell
cAMP
Hyperpolarization
Sinus node AV node
Protein kinase A
0 0
2+
Ca influx mV mV
–50 –50
83
Negative chronotropism Negative dromotropism
Despopoulos, Color Atlas of Physiology © 2003 Thieme
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