|
A) electrophysiologically defined subpopulations
|
|
Neuron class
|
MVC
|
CVC
|
SM
|
PM
| |
|
Transmitter
|
NE
|
NE
|
ACH
|
NE
| |
|
Peptide cat
|
NPY
|
NPY
|
VIP
| | |
|
GAL
|
GAL
|
CGRP
|
GAL
| |
|
Peptide guinea pig
|
NPY
|
NPY
|
VIP
| | |
| |
DYN
|
CGRP
|
DYN
| |
|
major stimulus
|
|
human
|
baro-inhibition
|
cooling general
|
warming general
| | |
|
cat
|
baro-inhibition
|
temperature
|
vibration
|
hypothalamic stimulation
|
(selected from [17]
|
|
B) subpopulations defined by RNA sequencing
|
|
Neuron class
|
NA 1
|
NA 2
|
NA 3
|
NA 4
|
NA 5
|
ACH 1
|
ACH 2
|
|
Average transcript number per cell
|
|
TH
|
69
|
105
|
93
|
85
|
100
|
25
|
1
|
|
DBH
|
48
|
83
|
71
|
79
|
67
|
37
|
21
|
|
DDC
|
43
|
105
|
91
|
107
|
88
|
28
|
12
|
|
VMAT 2
|
29
|
63
|
58
|
38
|
34
|
4
|
2
|
|
CHAT
|
zero
|
zero
|
zero
|
zero
|
zero
|
2
|
1
|
|
VACHT
|
zero
|
zero
|
zero
|
zero
|
zero
|
7
|
9
|
|
NPY
|
117
|
678
|
478
|
63
|
22
|
74
|
11
|
|
SOM
|
zero
|
1
|
zero
|
zero
|
zero
|
3
|
53
|
|
VIP
|
1
|
1
|
1
|
zero
|
zero
|
367
|
200
|
|
CGRP (CALCA/B)
|
zero
|
zero
|
zero
|
zero
|
zero
|
4/3
|
6/5
|
|
defined target
| |
erector
| | |
erector
| | |
| |
muscle
| | |
muscle
| | |
|
compiled from [80], supplementary figure nn.4376 – S4
|
- The table displays a selected set of sympathetic neurons derived from electrophysiological analysis (A) or from RNA sequencing profiles (B)
- Electrophysiological analysis (A) defined a large number of sympathetic neuron classes named according to the target tissue supplied by the nerves from which recordings are made: MVC Muscle vasoconstrictor, SVC Skin vasoconstrictor, SM Sudomotor and PM Pilomotor among other populations not listed here. Classical neurotransmitters NE Norepinephrine and ACH Acetylcholine as well as neuropeptides detected in cat and guinea pig are provided for the individual neuron classes. In addition, the major stimuli detected by microneurography in humans and extracellular recording from prepared nerve filaments in cats are indicated to demonstrate the different reflex circuits and functional integration of the neuron classes
- RNA sequencing profiles analyzed by unsupervised clustering algorithms (B) from material derived from stellate and thoracic mouse sympathetic ganglia disclosed a number of noradrenergic (NA 1 to 5) and cholinergic (ACH 1, 2) neuron populations distinguished by the preferential expression of certain genes. The numbers shown for the different genes give the average number of transcripts for the respective gene in a cell of a given population. Interestingly transcripts for noradrenergic markers TH Tyrosine hydroxylase, DBH Dopamine beta hydroxylase, DDC DOPA decarboxylase and the VMAT 2 Vesicular monoamine transporter 2 are not absent from the cholinergic neuron populations. On the other hand, cholinergic markers CHAT choline acetyltransferase and the VACHT Vesicular acetylcholine transporter are not detectable in the noradrenergic neuron populations. The NPY Neuropeptide is not absent from cholinergic neurons while SOM Somatostatin and VIP Vasoactive intestinal polypeptide are largely restricted to one or both cholinergic neuron populations. The targets given for the NA 2 and NA 5 are derived from developmental analysis and genetic labeling of specifically expressed genes. The high level SOM expression in ACH2 is characteristic for sudomotor neurons
