ascending pathway thermal pain receptor in finger to brain response thermal pain receptor in finger...
TRANSCRIPT
Organization of Nervous System
Brain
CentralNervousSystem(CNS)
Spinalcord
VisceralStimuli
SensoryStimuli
AutonomicNervous System
SomaticNervous System
AfferentDivision
PeripheralNervousSystem
(PNS)Efferentdivision
ParasympatheticNervous System
SympatheticNervous SystemMotor Neurons
Effector Organs(made up of muscle and gland tissue)
Skeletal MuscleSmooth MuscleCardiac Muscle
Glands
(Output from CNSTo periphery)
(Input from CNSTo periphery)
Response
Thermalpain receptorin finger
Afferentpathway
Efferent pathway
Ascending pathway
Components of a reflex arc
Receptor
Afferent pathway
Integrating center
Efferent pathway
Effector organs
to brain
Triceps(exensor)
Biceps(flexor) Integrating center
(spinal cord)
Effectororgans
Stimulus
= Stimulates= Inhibits= Synapse= Excitatory interneuron= Inhibitory interneuron
Brain Stem
Cervical Spinal Cord
PS
Sym
PS
A
Lumbar Spinal Cord
Sacral Spinal Cord
Thoracic Spinal Cord
Cranisosacralparasympatheticnerves
Effectororgans:
Cardiacmuscle
Smoothmuscle
Mostexocrineglands andsomeendocrineglands
= Sympathetic system= Parasympathetic system
= Cell body= Axon terminal
Sympathetic ganglion chain
Terminalganglion
Spinalcord
ThoracolumbarSympatheticnerves
AChNE
AChACh
= Preganglionic fiber= Postganglionic fiber
ACh = Acetylcholine NE = Norepinephrine E = Epinephrine
Terminalganglion
ACh
ACh ACh
E, NE
Collateralganglion Collateral
ganglion
Blood
NE
Preganglionic neuronPostganglionic neuron
Reproductive system
Urinary system
Sympathetic trunk
Vasomotor fibersto lower extremity
To p
erip
hera
l blo
odve
ssel
s (v
asom
otor
)S
wea
t gla
nds
(sud
omot
orH
air f
olic
le m
uscl
e (p
ilom
otor
)
Eye
Blood vessels of head
Glands associated with eye, nasal cavity and oral cavity
Respiratory system
Circulatory system
Digestive system
Celiac ganglion
Descendingautonomicpathways
Hypothalamus
Superior cervical ganglion
Inferiormesenteric
ganglion
Superiormesentericganglion
Kidney
Adrenal
Descending autonomic pathways
Accessory oculomotorNucleus (Edinger-Westphal)
Salivatorynuclei
SuperiorInferior
Dorsal vagal nucleus
Preganglionic neuronPostganglionic neuron
Urinary systemReproductive system
Digestive system
Circulatory system
Respiratory system
Blood vessels andglands of head
Eye and lacrimal gland
Hypothalamus
Ciliary ganglion
Submandibular ganglion
Otic ganglion
S2
S3
S4
NERVES
ACh
ACh
+ EXOCRINE GLANDS+ SMOOTH MUSCLE OF G.I. TRACT– HEART RATE
+ SWEAT GLANDS– BLOOD VESSELS (Some)
+ HEART SMOOTH MUSCLE+ SPLEEN OF:+ BLOOD VESSELS – G.I. TRACT (Most) – LUNGS
SKELETALMUSCLE
POSTGANGLIONICNERVES:
GANGLION:
PREGANGLIONICNERVES:
A U T O N O M I C N E R V O U S S Y S T E M
PARASYMPATHETIC SYMPATHETIC SOMATIC
CHOLINERGICNERVES
ADRENERGICNERVES
CHOLI-NERGICALL
EFFECTORORGANS:
Adr
enal
Med
ulla
ACh NOREPI
C E N T R A LN . S .
ACh ACh
EPI
ACh
Via theBlood
ACh
The main effects of the autonomic nervous system
Organ
Sympathetic
Receptor type
Parasympathetic
Receptor type
Heart
SA node Rate β1 Rate M2 Atrial muscle Force β1 Force M2 AV node Automaticity β1 Cond. vel. M2 AV block Ventricular muscle Automaticity β1 No effect Force Blood vessels Arterioles Coronary Constriction α Muscle Dilatation β2 No effect Viscera Skin Brain
Constriction
α
No effect
Erectile tissue Salivary gland
Constriction α α
Dilatation ? M3
Veins Constriction α No effect Dilatation β2 Viscera Bronchi Smooth muscle No sympathetic innervation, β2 Constriction M3 but dilated by circulating epinephrine Glands No effect Secretion M3 GI tract Smooth muscle Motility α2, β2 Motility M3 Sphincters Constriction α2, β2 Dilatation M3 Glands No effect Secretion M3 Gastric acid secretion M1 Uterus pregnant Contraction α Variable non-pregnant Relaxation β2 Male sex organs Ejaculation α Erection ? M3 Eye Pupil Dilatation α Constriction M3 Ciliary muscle Relaxation (slight) β Contraction M3 Skin Sweat glands Secretion (mainly cholinergic) α No effect Pilomotor Piloerection α No effect Salivary glands Secretion α, β Secretion M3 Lacrimal glands No effect Secretion M3 Kidney Renin secretion β2 No effect Liver Glycogenolysis α, β2 No effect Glyconeogenesis
Vm (mV)
Vm (mV)
fiber
Target organs
Sympatheticpreganglionicfiber
Sympatheticpostganglionic
Acetylcholine Norepinephrine Epinephrine
Spinal cord
Adrenalmedulla
Blood fiber
Target organs
inactiveA-kinase
regulatorysubunit
catalyticsubunit
complex ofcyclic AMP and
regulatory subunits active catalyticsubunit
cyclic AMP
1 molecule ofsignaling ligand
receptor protein
each activated receptor proteinactivates many molecules of Gprotein, each of which in turnactivates an adenylate cyclasemolecule
each activated adenylatecyclase molecule generatesmany cAMP molecules
each cAMP moleculeactivates 1 moleculeof protein kinase
each kinase molecullephosphorylates andthereby activates manycopies of enzyme X
each copy of enzymeX produces manymolecules of product
cAMP
AMPLIFICATION
AMPLIFICATION
AMPLIFICATION
AMPLIFICATION
G protein
acivatedadenylate cyclase
proteinkinase
enzyme X
products ofenzyme X
GTP
Phosphatidylinositol Polyphosphoinositides
Ptdins Ptdlins4P Ptdins4,5P2
Ins 1,4,5P3
AGONIST
Diacylglycerol
d
a
cb
β1 Linked to stimulation of adenylyl cyclaseβ2 Linked to stimulation of adenylyl cyclase α1 Linked to phospholipase C mobilization of intracellular Ca2+
α2 Linked to inhibiion of adenylyl cyclase
Classification of Noradrenergic Receptors Linked to Second-messenger Systems
Type Second-messenger system Gene family Location
Cerebral cortex, cerebellumCerebral cortex, cerebellum
Superfamily of G-protein Brain, blood vessels, spleen coupled receptors
Presynaptic nerve terminals throughout the brain
MUSCARINIC ACETYLCHOLINE RECEPTORS
Nomenclature M1 M2 M3 M4 M5
Predominant Effectors
IP3/DG cAmp K+ channel
IP3/DG cAmp IP3/DG
Subtypes of muscarinic receptors
M1
M2
M3
Type
“Neural”
“Cardiac”
“Glandular”
Main locations
Neural
Cardiac
Exocrine glands
CNS (cortex, hippocampus) Atria Smooth muscle Ganglia (enteric, autonomic) Conducting tissue Vascular endothelium Gastric Neural Parietal cells Presynaptic terminals Effects Cellular IP3, DAG cAMP IP3
Depolarization Inhibition Stimulation Excitation (slow epsp) ( Gk, iCa) ( [Ca]i) ( Gk) Slow ipsp Functional CNS excitation (? memory) Cardiac inhibition Secretion Gastric acid secretion Presynaptic inhibition Smooth muscle
contraction Gastrointestinal motility Neural inhibition Vasodilatation (via NO) Agonists ACh ACh ACh CCh CCh CCh McNA343 Antagonists Atropine Atropine Atropine Pirenzepine Gallamine HHSD* Dicyclomine AF-DX 116
*HHSD = hexahydrosiladifenol
Effects mediated by adrenoceptor subtypes
Adrenoceptor
Tissue
α1
α2
β1
β2
Smooth muscle
Blood vessels Constrict Contract Dilate Bronchi Constrict Dilate GI tract Non-sphincter Relax Relax (hyperpolarization) (no hyperpolarization) Sphincter Contract Uterus Contract Relax Bladder Detrusor Relax Sphincter Contract Seminal tract Contract Iris (radial) Contract Ciliary muscle Relax Heart Incr rate Incr force Skeletal muscle Tremor Liver Glycogenolysis Glycogenoloysis K+ release Fat Lipolysis ( β3-receptor) Nerve terminals Adrenergic Decr release Incr release Cholinergic (some) Decr release Salivary gland K+ release Amylase secretion Platelets Aggregation Mast cells Inhibition of histamine release
Second messengers
IP3, DAG
cAMP
cAMP
cAMP
inactivephosphorylaskinase
activephosphorylaskinase
inactive A-kinase
active A-kinase
cAMP
GLYCOGEN GLUCOSE 1-PHOSPHATE
GLYCOLYSIS