Autonomic Nervous System
Sympathetic Nervous
system
I
= Increase
D=
Decrease
Sympathetic
Nervous System
|
|
a1 |
a2 |
b1 |
b2 |
|
NA |
+++ |
+++ |
++ |
+ |
|
Adr |
++ |
++ |
+++ |
+++ |
|
|
|
|
|
|
Haemodynamic Effects of Adr and NA
|
|
Adr |
NA |
|
Heart |
|
|
|
HR |
I
+ |
D
- |
|
SV |
I
++ |
I++ |
|
CO |
I
+++ |
I-/0 |
|
Blood
vessels |
|
|
|
Coronary |
I++ |
I++ |
|
Muscle |
I+++ |
0/D
- |
|
Cutaneous |
D
- - |
D
- - |
|
Renal |
D
- |
D
- |
|
Splanchnic |
I+++ |
I
+/0 |
|
Cerebral |
I+ |
0/D
- |
|
Blood
Pressure |
|
|
|
Systolic |
I+++ |
I
+++ |
|
Diastolic |
0/D
-/I + |
I
++ |
|
MAP |
I
+ |
I
++ |
|
Pulmonary |
I
++ |
I
++ |
|
TPR |
D
- |
I
++ |
|
Metabolic |
|
|
|
O2
use |
I
++ |
0/I
+ |
|
Glucose |
I
+++ |
0/
I + |
N.B Although
alpha2 receptors are present in vessel walls agonists overall have
antihypertensive effect mediated thorough central alpha2 stimulation in the
medulla
|
Organ |
Receptor |
Action |
|
Blood
vessels |
|
|
|
Skeletal M |
b2 |
Relaxes |
|
|
a |
Contracts |
|
Cutaneous |
a |
Contracts |
|
|
|
|
|
CVS |
|
|
|
Muscle |
b1 |
I
Contractility |
|
SA node |
b1 |
I Rate |
|
|
M2 |
D Rate |
|
AV node |
b1 |
I Automaticity |
|
|
M2 |
D Conduction
velocity |
|
|
|
|
|
GIT |
|
|
|
Walls |
a1, b2 |
Relaxes |
|
|
M3 |
Contracts Secretion |
|
Sphincters |
a1 |
Contracts |
|
|
|
|
|
Urinary |
|
|
|
Bladder wall
(and prostate wall) |
b2 |
Relaxes |
|
a1 |
Contracts |
|
|
Eye |
|
|
|
Pupil |
a |
Dilatation |
|
|
M3 |
Constriction |
|
Ciliary
muscle |
b |
Relaxation |
|
|
M3 |
Contraction |
|
Skin |
|
|
|
Sweat glands |
SNS but
cholinergic |
Secretion |
|
Pilomotor |
a |
Piloerection |
|
Uterus |
|
|
|
Non-Pregnant |
b2 |
Relaxation |
|
Pregnant |
a |
Contraction |
|
Other |
|
|
|
Salivary
glands |
a,b |
Secretion |
|
|
M3 |
Secretion |
|
Liver |
a, b2 |
Glucose
production |
|
|
|
|
|
|
|
|
|
|
|
|
