Norepinephrine (NE) Epinephrine(E) Receptors

NorepinephrineNorepinephrine (NE)(NE)EpinephrineEpinephrine(E) (E)

ReceptorsReceptors

ByBy GGüüll GGüünaynaySevilaySevilay AkkAkköösese

GGöözde zde ÇÇolakolak

Norepinephrine, epinephrine, arein the class of catecholaminesand they bind to adrenergic

receptors.

Norepinephrine (noradrenalinNorepinephrine (noradrenalin))

Released by the sympathetic Released by the sympathetic postganglionic nerve endingspostganglionic nerve endings

5 6

CHOH CH214 NH2HO

HO3 2

Epinephrine (adrenalinEpinephrine (adrenalin))

A methyl derivative of norepinephrine. It is A methyl derivative of norepinephrine. It is primarily primarily an emergency hormone an emergency hormone produced by the adrenal medulla. produced by the adrenal medulla.

5 6

CHOH CH214 NHCH3HO

HO3 2

Sympathetic Sympathetic DivisionDivision

Both NE and E affect Both NE and E affect sympathetic nerves sympathetic nerves --NE is neurotransmitterNE is neurotransmitter--E is hormoneE is hormone

Increase heart rate and Increase heart rate and strength of contractionstrength of contractionMobilize glucose from liverMobilize glucose from liverInhibit digestive activityInhibit digestive activity

SynthesisSynthesis of E of E andand NENE

Adrenergic Receptors Adrenergic Receptors SevenSeven--pass pass transmembrane transmembrane proteins that are proteins that are coupled to G proteinscoupled to G proteinsThere are multiple There are multiple receptor types which receptor types which are differentially are differentially expressed in different expressed in different tissues and cells. tissues and cells.

Two Two main main families of adrenergic receptorsfamilies of adrenergic receptorsAlpha (Alpha (αα))Beta (Beta (ßß))

NE,E

E

α

ß

Adrenergic Adrenergic Receptor Receptor Subtypes Subtypes

Main Type of Main Type of Adrenergic ReceptorsAdrenergic Receptors

ReceptorReceptor AgonistsAgonists SecondSecond MessengerMessenger G proteinG protein

alphaalpha11 ((αα11)) E>NEE>NE IPIP33/Ca/Ca2+2+; DAG; DAG GGqq

alphaalpha22 ((αα22)) NE>ENE>E ↓↓ cyclic AMPcyclic AMP GGii

betabeta11 ((ββ11)) E=NEE=NE ↑↑ cyclic AMPcyclic AMP GGss

betabeta22 ((ββ22)) E>>NEE>>NE ↑↑ cyclic AMPcyclic AMP GGss

ProcessProcessαα11--receptorreceptor

(IP(IP33, DAG), DAG)

αα22--receptorreceptor

((↓↓ cAMPcAMP))

ββ11--receptorreceptor

((↑↑ cAMPcAMP))

ββ22--receptorreceptor

((↑↑ cAMPcAMP))

CarbohydrateCarbohydratemetabolismmetabolism

↑↑ liver liver glycogenolysisglycogenolysis No effectNo effect No effectNo effect

↑↑ liver/muscle liver/muscle glycogenolysisglycogenolysis;;↑↑ liver liver gluconeogenesisgluconeogenesis;;↓↓ glycogenesisglycogenesis

FatFatmetabolismmetabolism No effectNo effect ↓↓ lipolysislipolysis ↑↑ lipolysislipolysis No effectNo effect

HormoneHormonesecretionsecretion No effectNo effect ↓↓ insulin insulin

secretionsecretion No effectNo effect ↑↑ insulin and insulin and glucagonglucagonsecretionsecretion

References:References:http://www.biohttp://www.bio--logicsolutions.com/neurolog.htmlogicsolutions.com/neurolog.htmhttp://www.neuro.wustl.edu/neuromuscular/lab/catechol.http://www.neuro.wustl.edu/neuromuscular/lab/catechol.htm#nehtm#nehttp://arbl.cvmbs.colostate.edu/hbooks/pathphys/endocrihttp://arbl.cvmbs.colostate.edu/hbooks/pathphys/endocrine/adrenal/medhormones.htmlne/adrenal/medhormones.htmlhttp://www.blackwellpublishing.com/matthews/neurotranhttp://www.blackwellpublishing.com/matthews/neurotrans.htmls.htmlhttp://www.blackwellpublishing.com/matthews/neurotranhttp://www.blackwellpublishing.com/matthews/neurotrans.htmls.htmlhttp://www.creighton.edu/~tpisarri/Powerpoints/Lecture1http://www.creighton.edu/~tpisarri/Powerpoints/Lecture11.ppt#339,25,Adrenergic Receptors1.ppt#339,25,Adrenergic Receptorshttp://www.sosu.edu/faculty/mturnage/Fall%2003%20folhttp://www.sosu.edu/faculty/mturnage/Fall%2003%20folders /ders /