Receptorarchitecture and Neural Systems

Karl Zilles

Institute of Neuroscience and Medicine INM-1 Research Centre Jülich

and University Hospital of Psychiatry, Psychotherapy and

Psychosomatics RWTH Universität Aachen

Receptors are protein complexes in the cell membrane, to which transmitters selectively bind.

ionotropic receptors have an integrated ion channel and regulate ion fluxes between extra- and intracellular space

metabotropic receptors are linked to intracellular second messenger systems, and control metabolic pathways, ion channels, gene activity, etc.

It provides insight into the molecular basis of the resting state condition.

Most of the brain‘s energy consumption is used for maintaining ion

channel functions during resting state. Only a minority of the energy is required during stimulation conditions.

Receptor mapping overcomes limitations of unimodal brain mapping approaches

It provides brain maps based on molecules which are key elements of

signal transmission within and between neural systems

Areas within a given functional system have similar multireceptor expression patterns. Different functional systems differ by those expression patterns

What does receptor mapping provide?

R

Example: Ionotropic Transmitter Receptors

postsynaptic ionotropic receptor

transmitter

ion channel

postsynaptic membrane

presynaptic ionotropic receptor

presynaptic membrane

axonal bouton

AMPA

Dendrite

PSD

postsynaptic

presynaptic

Dendrite

Spine

Postsynaptic density PSD

NMDA NR1

Joachim Lübke, Research Center Jülich, Germany (unpublished)

NMDA NR1

AMPA

NMDA and AMPA are the most abundant glutamate receptor types in the human cerebral cortex. Method: Cryo-Electron-Microscopy and Immunocytochemistry with specific antibodies labeled with gold nanoparticles of different size (for AMPA 9 nm, for NMDA 12 nm)

Adenosin A1 D1, D2, D4

D1, D2, D4

Dopamine

AMPA, NMDA, kainate

AMPA, NMDA, kainate

AMPA, NMDA, kainate

AMPA, NMDA, kainate

Glutamate

GABAA, bz.binding site

GABAA, bz.binding site

GABAA, bz.binding site

GABAA, bz.binding site

GABAB

GABAB

GABAA, bz.binding site

GABAB

GABA

nicotinic, M1, M2, M3

nicotinic, M1, M2, M3

Acetylcholine

α1, α2

α1, α2

Noradrenaline

5-HT1A, 5-HT2

5-HT1A, 5-HT2

Serotonin

How to map receptor distributions:

• in vivo receptor PET

• in vitro quantitative receptor autoradiography

• immunohistochemistry of receptor proteins and subunits

• transcriptomics

HG05/00

Sulcus centralis

slab 2 native

slab 2 frozen

at -70° C

slab 2

Quantitative in vitro Receptor Autoradiography: Method (1)

Gyrus praecentralis

Cryostate serial sections (10 – 20 µm) – mounting on glass slides

Incubation of alternating serial sections with tritium-labeled ligands Labeling of different receptors of all classical transmitter systems (Glutamate, GABA, Acetylcholine, Dopamine, Serotonin, Noradrenaline) Exposition against β-sensitive film together with radioactive scales Digitization, quantification and colour coding of the film Identification of cytoarchitectonic areas by comparison with neighbouring cell-body stained sections

Quantitative in vitro Receptor Autoradiography: Method (2)

Neurotransmitter Receptor [3H] Ligand Glutamate AMPA AMPA

Kainate kainate NMDA MK-801

GABA GABAA muscimol, SR 95531

GABAB CGP 54626

BZ Flumazenil Acetylcholine M1 pirenzepine

M2 oxotremorine-M, AF-DX 384

M3 4-DAMP

N epibatidine Noradrenaline α1 prazosin

α2 UK 14,304 RX-821002

Serotonin 5-HT1A 8-OH-DPAT

5-HT2 ketanserin

Dopamine D1

D2

SCH 23390 Fallypride or Raclopride

Histological staining: Cell bodies Myelin

Examined receptor binding sites

Gennari‘s stripe V2

V2

V1

V1

Myelin

vertical meridian

vertical meridian

GABAA Receptor

V2

V2

V1

V1

vertical meridian

Sulcus calcarinus

Zilles, K., Palomero-Gallagher, N. , Schleicher, A.: Transmitter receptors and functional anatomy of the cerebral cortex. J. Anat. 205: 417-432 (2004)

vertical meridian

Entorhinal-Hippocampal System

medial lateral

ventral

dorsal

Dent

CA4

CA1

Sub Prsub

Ent

35

36

n.d. n.d.

fi

Parsub

1

2

3 trisynaptic glutamatergic system: 1 perforant path 2 mossy fibers 3 Schaffer collaterals

general neocortical input CA2

CA3

INPUT:

temporal and perirhinal input to subiculum

OUTPUT: from the subiculum and CA1 to temporal, parahippocampal, perirhinal, cingulate, prefrontal, and orbitofrontal areas

cingulate, superior temporal, dorsolateral prefrontal, and IPL input to presubiculum

Why are architectonic studies essential for understanding the organization of neural systems?

sub CA1 mol

CA2

fimbria CA3

Kainate NMDA

AMPA

perforant path

mossy fibres

Schaffer collateral

CA1 mol

CA1

mol CA3 CA2

Glutamatergic terminals of the perforant path and the Schaffer collaterals

Glutamatergic terminals of the mossy fibers

Glutamatergic terminals of the perforant path and the Schaffer collaterals

295 464 633 802

221 357 493 629 417 632 486 1061 fmol/mg protein fmol/mg protein

fmol/mg protein

Primary Sensory Cortices

96 208 320 432 fmol/mg protein

cholinergic muscarinic M2 receptor

Toga AW, Thompson PM, Mori S, Amunts K, Zilles K (2006) Towards multimodal atlases of the human brain. Nature Rev. Neurosci. 7: 952-966 Zilles K, Amunts K (2009) Receptor mapping: Architecture of the human cerebral cortex. Current Opinion Neurol. 22: 331–339

primary auditory

multimodal temporal

association

cingulate

unimodal auditory

pre/para- subiculum

entorhinal

insular

motor

parietal

primary somatosensory 3b

3a

Macaque Brain

Human Brain

primary somatosensory cortex

low density high density

primary auditory cortex

motor cortex

motor cortex sc

sc

Cholinergic muscarinic M2 receptor

primary auditory cortex

primary somatosensory cortex

Kainate receptor [3H] kainate

AMPA receptor [3H] AMPA

154 379 604 829

GLUTAMATE SYSTEM

668 1084 1499 1915

pre/para- subiculum

entorhinal

multimodal temporal

association

cingulate

unimodal auditory

primary auditory

sensorimotor

primary auditory

multimodal temporal

association

cingulate

fmol/mg protein

unimodal auditory

pre/para- subiculum

entorhinal

insular insular

sensorimotor

Receptor Fingerprints

Dopamine

Acetylcholine

Serotonin

Glutamate

Noradrenaline GABA

Low denisty

High density

AMPA Kainate NMDA M1 M2 M3 nicotinic

α1 α2 GABAA 5-HT1A 5-HT2 D1 D2

Multimodal visualization of receptor organization in human cerebral cortex

Zilles, K., Schleicher, A., Palomero-Gallagher, N., Amunts, K.: Quantitative analysis of cyto- and receptorarchitecture of the human brain, pp. 573-602. In: Brain Mapping: The Methods, 2nd edition (A.W. Toga and J.C. Mazziotta, eds.). Academic Press (2002)

A receptor fingerprint is… AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

nACh

α1

α2

5-HT1A

5-HT2

D1

area 4

caudate putamen

0

500

1000

1500

2000

2500

3000

„Receptor Fingerprints“

AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT2

D1

1000

2000

3000

Hippocampus CA1-3

0

primary motor cortex

AMPA kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT2

D1

0

5-HT1A 5-HT1A 1000

2000

3000

What receptors tell us about laminar segregation and input-output relations

in the cerebral cortex

molecular layer I

outer granular layer II

inner granular layer IV

outer pyramidal layer III

inner pyramidal layer V

polymorphic layer VI

CYTOARCHITECTURE

thalamo- cortical input

cortico- cortical input

CONNECTIVITY SYNAPTIC DENSITY

cortico- -cortical, -striatal,

-thalamic, -bulbar, and

-spinal output

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

L. I

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

Ll. II-III

Receptor Fingerprints of the primary visual cortex: layer specificity

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

L. IV

L. V

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1 L. VI

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

Layer IV: Thalamo-cortical Input

4

modality-specific balance between receptors

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

primary somatosensory (touch)

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

primary visual

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

parietal association (visually guided grasping)

0

1000

2000

3000 AMPA

kainate

NMDA

GABAA

GABAB

BZ

M1

M2 M3

N

α1

α2

5-HT1A

5-HT2

D1

prefrontal association (working memory)

Cluster analysis of the multi-receptor fingerprints of BROCA‘s region, prefrontal and motor cortex

6r1

4

47

6v1

op9

op8

45

44

prefrontal

primary motor

premotor

language

0.2 0.3 0.4 0.5 0.6 0.7 0.8

cort

ical

are

a

Amunts, K., Lenzen, M., Friederici, A.D., Schleicher, A., Morosan, P., Palomero-Gallagher, N., Zilles, K.: Broca's region: Novel organizational principles and multiple receptor mapping. PLoS Biology 8(9): e1000489. doi:10.1371/journal.pbio.1000489 (2010)

4

6v1

6r1

44 45

47

op8 op9

Whole brain hierarchical cluster analysis based on multi-receptor fingerprints - Normalization: divide by mean - Euclidean distances, Ward linkage - Cophrenetic coefficient: 0.58

Eucl

idea

n di

stan

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0 1

2 3

4 5

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7lp

7mp 31

7la

7ma

v2d

v2v

Oc4

d O

c3d

d23 29

30

BA1

3a

Te

1 Te

2 Te

3 Te

4 B

A2

5m

7pc 5l

BA3

8 B

A4

BA8

p2

4'

BA4

4 B

A45 3b

Oc3

v v4

v FG

1 FG

2 v1

6d

a24'

O

P 24

v23

32'

PF

PFm

PG

p PG

a PF

cm

PFop

PF

t B

A47

10m

s3

2 p3

2 25

BA2

0‘

BA3

6 dg

subi

c en

t C

A

motor Broca somato -

-sensory domaine

auditory anterior cingulate- prefrontal

entorhinal -hippocampal

circuit

inferior parietal

multimodal cortex perilimbic

proisocortex

visual

ventral stream

retro- splenial

visual superior parietal

dorsal stream

sensorimotor limbic

Cluster analysis of the human cingulate cortex: A multi-region model based on receptor fingerprints

Palomero-Gallagher, N., Vogt, B.A., Schleicher, A., Mayberg, H.S., Zilles, K. (2009) Receptor architecture of human cingulate cortex: Evaluation of the four-region neurobiological model. Human Brain Mapping 30: 2336-2355

Eucl

idea

n di

stan

ce (W

ard

linka

ge)

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

23d

23c 31

d23

v23 30

29l

29m

24a

24b

24cv

24cd

32

p24a

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p24b

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24dv

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RSC ACC

MCC

PCC aMCC pMCC

emotion

decision motor control

visuo- spatial

attention memory

limbic memory

auto

nom

ic

cont

rol

Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich

Katrin Amunts Svenja Caspers Joachim Lübke Hartmut Mohlberg Nicola Palomero-Gallagher Axel Schleicher

Thanks to: