human brain slices recordings

www.neuroservice.com

Human Brain Slice

Recordings

May, 2009


PATCH-CLAMP RECORDINGS OF HUMAN BRAIN

SLICES

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&


HUMAN BRAIN CORTEX FROM NEUROSURGICAL

RESECTIONS Small areas of cortical brain tissue are obtained from adult patients undergoing neurosurgical resections for purely medical reasons.

For tumor resections, non-infiltrated neocortical tissue must be removed to provide access to the deeper laying tumor and it is this tissue that serves as the substrate for the electrophysiological recordings.

In all cases, surgery is approved by a completely independent multidisciplinary Board of Physicians (Neurosurgical Tumor Board or Case Conference of Epilepsy Surgery) who have no scientific or any other interest in the use of the brain tissues.

Before the surgery, patients give informed consent that brain tissue resected to assure the best possible surgical outcome will be used for fundamental research and/or compound testing. Their written consent is filed, as supervised by the Ethical Committee from the University of Freiburg, and in accordance with both national and international guidelines.


HALLMARKS OF HEALTHY HUMAN CORTEX

All collected tissue is free of: Gliosis

Ischemia

Inflammation

Tumor infiltration

Tumor infiltration MiB1 monoclonal antibody against Ki67 tumor marker; bars = 50 µm

Absence of

labeled tumor

cells in a cortical

slice from

healthy tissue

Cortical tissue

infiltrated by

labeled tumor

cells (black) from

glioma


LABELING TO REVEAL NORMAL TISSUE

ORGANIZATION

Immunofluorescence staining against NeuN

Temporal neocortex

bar = 300 µm

Higher magnifications of layer II, III and IV/V respectively; bar = 30 µm


PRESERVATION OF PYRAMIDAL CELLS AND

INTERNEURONS

50

µm

BIOCYTIN PV STAINING OVERLAY

Interneurons Pyramidal cells

Avidin-Alexa 488 labeling Immunocytochemical staining with a monoclonal antibody directed against Parvalbumin (PV+ cells = red, filled FS-IN = yellow)


PASSIVE PROPERTIES OF NEURONS

Firing pattern

AP kinetics

Input resistance

Pyramidal cells (layer II/III) Fast Spiking Interneuron


AMPA/KAINATE-EVOKED CURRENTS: NO

RECTIFICATION

Current traces Current-voltage relationship

Current-voltage relation of evoked AMPA/KA receptor-mediated excitatory postsynaptic currents (eEPSCs) in layer II/III of human neocortical tissue.


AMPA/KAINATE-EVOKED CURRENTS: CNQX

BLOCK

Control

CNQX, a selective AMPA/KA receptors antagonist, reversibly blocks eEPSCs.

CNQX

Recovery


IV CURVE OF SYNAPTIC NMDA-RECEPTOR MEDIATED

CURRENTS


NMDA receptor currents recorded in the presence of CNQX 10 μM and SR 95531 10 μM.


NMDA CURRENTS: (R)-CPP BLOCK

R-CPP 10 µM

Control

Evoked-currents are completely blocked by a selective NMDA antagonist.


GABAA RECEPTOR-MEDIATED IPSCs


Focally evoked IPSCs by extracellular stimulation


GABAA IPSC: SR95531 BLOCK

Control

SR95531


USE OF HUMAN BRAIN SLICE

ELECTROPHYSIOLOGY

A few possibilities…

DRUG DISCOVERY PROJECT PROGRESSION

early-stage POC study for new biological target under study

late-stage profiling of advanced candidate

candidate support for development compound

spot check for cross-species translation within chemical series

IDEA DRUG


A PARTNERSHIP CUSTOMIZED TO CLIENT NEEDS

A unique contract with Neuroservice

Expert Interface with Customer

Customer Relationship Management

Quotation & Contractual Paperwork

Contract and Project Management

Raw data validation & Final report

Expert Interface with Customer

Human tissue management

Protocol design

Patch Clamp recording

Domaine de St Hilaire

595, rue Pierre CS 30531

13 593 Aix-en-Provence

Cedex 3

FRANCE

Tel : +33 (0)442 991 220

[email protected]



human brain slices recordings

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