Receptors and signal transduction in the ANS

1
Receptors and signal transduction in the ANS
Cholinergic Receptors
Nicotinic
Muscarinic
Ganglionic
Skeletal Muscle
Neuronal CNS
2
Receptors and signal transduction in the ANS
Nicotinic Receptors
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Receptors and signal transduction in the ANS
Nicotinic Receptors
4
Receptors and signal transduction in the ANS
Cholinergic Receptors
Nicotinic
Muscarinic
M1
M5
M3
M4
M2
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Receptors and signal transduction in the ANS
Muscarinic receptors are 7 transmembrane domain,
G-protein coupled receptors
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Receptors and signal transduction in the ANS
Muscarinic receptors(M1, M3, M5)
NH
3
Phospho
-
()
G
lipase C
q
PIP
2
IP
Diacylglycerol
COOH
3
2
Increase Ca
Activate Protein
Kinase
C
Response
7
Receptors and signal transduction in the ANS
Muscarinic Receptors
(M2 and M4)
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Receptors and signal transduction in the ANS
Adrenergic Receptors
a1A
b3
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Receptors and signal transduction in the ANS
a1-AdrenergicReceptors
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Receptors and signal transduction in the ANS
a2-AdrenergicReceptors
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Receptors and signal transduction in the ANS
b-AdrenergicReceptors
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Heart
Rate of Contraction
Increase
Decrease
M
2
Force of Contraction
Increase
Decrease
M
2
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
a
Arteries (most)
Vasoconstriction
----------
--
1
a
Veins
Vasoconstriction
----------
--
2
b
Skeletal Muscle
Vasodilation
----------
--
2
Endothelium
----------
--
Release EDRF
M
3
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Lung
Bronchiolar smooth muscle
Bronchodilation
Bronchoconstriction
M3
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Genitourinary, smooth muscle
b2
Bladder wall
Relaxation
Contraction
M3
a
Ureter
Contraction
Relaxation
M3
1
a
Sphincter
Contraction
Relaxation
M3
1
Uterus (pregnant)
Relaxation
b2
Variable
Contraction
M
3
Erection
Penis/vas deferens
Ejaculation
M3
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Gastrointestinal Tract
Salivary Glands
Increase secretion
Increase secretion
Smooth Muscle
a
b
Relaxation
M3
Walls
Contraction
,
2
2
a
Sphincters
Contraction
Relaxation
M3
1
Secretion
----------
--
Increase secretion
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Skin
a1
Hair follicles, Smooth muscle
Contraction, Piloerection
--------------
--
Sweat glands
--------------
M3
Thermoregulation
Increase secretion
--
--------------
Increase secretion
a1
Apocrine (stress)
--
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Eye
Iris
--------------
a1
Radial muscle
Contraction
--
Contraction
--
-------------
Circular muscle
M3
Contraction
Ciliary muscle
Relaxation
b2
M3
--------------
b2
Ciliary epithelium
Increase secretion of aqueous humor
--
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Physiology of the eye
Cornea
Canal of Schlemm
Trabecular meshwork
Circular muscle (M3)
Radial muscle (a1)
Sclera
Iris
Lens
Ciliary muscle (M3)
Ciliary epithelium (b2)
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Physiology of the eye
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Physiology of the eye
Circular muscle (M3 Receptors)
Pupil
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Physiology of the eye
Contraction of circular muscle leads to miosis
Pupil
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Physiology of the eye
Contraction of circular muscle leads to miosis
Pupil
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Physiology of the eye
Radial Muscle ( a1 Receptors)
Pupil
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Physiology of the eye
Contraction of radial muscle leads to mydriasis
Pupil
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Functional Responses Mediated by the ANS
Adrenergic
Cholinergic
Effector Organ
Response
Receptor
Response
Receptor
Metabolic functions
a1, b2
Liver
Glycogenolysis
--------------
--
Gluconeogenesis
b1, b3
Fat cells
Lipolysis
--------------
--
b
Kidney
--------------
--
Increase renin secretion
1
--------------
Pancreas
a2
Decrease insulin release
--