Dr Ragnhildur Thora Karadottir

Ragnhildur Thora Karadottir

University position

Wellcome Trust RCD Fellow

Dr Ragnhildur Thora Karadottir is pleased to consider applications from prospective PhD students.


Department of Veterinary Medicine



Research Themes

Cellular and Molecular Neuroscience

Clinical and Veterinary Neuroscience


My lab’s interests are neurotransmitter signalling to oligodendrocytes and their progenitor cells, in both health and disease.

Oligodendrocytes produce myelin (in the CNS), which speeds the propagation of the action potential. When the myelin sheath is lost or not formed, in diseases like cerebral palsy, spinal cord injury and multiple sclerosis, it causes mental and physical disability. We study how oligodendrocytes respond to neurotransmitters released from axons, both in the normal brain and in pathological conditions.

Oligodendrocyte precursor cells (OPCs) comprise 5% of the cells in the adult brain, where they are the main proliferative cells present. They can generate both neurons and glial cells, making them an important stem cell population in the adult brain. We study how neuronal activity can regulate OPC differentiation, in both the normal brain and pathological conditions.

myelinstaining in the cerebellum
Myelinated axons in the cerebellum
Click image to view full-size

Research Focus






stem cell

Clinical conditions

Alzheimer's disease

Cerebral Palsy


Multiple sclerosis

Spinal cord injury


Calcium imaging

Cell culture

Confocal microscopy

Electrophysiological recording techniques

Field potential recording

Fluorescence microscopy


Whole cell patch clamp



Guy Brown

Michael Coleman

Robin Franklin

Kristian Franze

Lisa Hall

Andras Lakatos

Steven Lee

Keith Martin

Lisa Saksida

Maria Spillantini

United Kingdom

David Attwell Web: http://www.ucl.ac.uk/npp/da....

Charles ffrench-Constant Web: http://www.crm.ed.ac.uk/researc...

Heidi Johansen-Berg Web: http://www.fmrib.ox.ac.uk/team/pr...


Gabriela Popescu Web: http://www.acsu.buffalo.edu/~popescu/

Edward Ruthazer Web: http://ruthazerlab.mcgill.ca

Fraser, J. Sim Web: http:// fjsim@buffalo.edu

Kristine Beate Walhovd Web: http://www.sv.uio.no/psi/eng...

Associated News Items

Key publications

Lundgaard I, Luzhynskaya A, Stockley JH, Wang Z, Evans KA, Swire M, Volbracht K, Gautier HO, Franklin RJ, Charles Ffrench-Constant, Attwell D, Káradóttir RT (2013), “Neuregulin and BDNF induce a switch to NMDA receptor-dependent myelination by oligodendrocytes.” PLoS Biol 11(12):e1001743 Details

Káradóttir R, Hamilton NB, Bakiri Y, Attwell D (2008), “Spiking and nonspiking classes of oligodendrocyte precursor glia in CNS white matter.” Nat Neurosci 11(4):450-6 Details

Káradóttir R & Attwell D (2006), “Combining patch-clamping of cells in brain slices with immunocytochemical labelling to define cell type and developmental stage” Nature Protocols 1(4):1977-1985 Details

Káradóttir R, Cavalier P, Bergersen LH & Attwell D (2005), “NMDA receptors are expressed in oligodendrocytes and activated in ischaemia” Nature 438:1162-1166



Blanco S, Dietmann S, Flores JV, Hussain S, Kutter C, Humphreys P, Lukk M, Lombard P, Treps L, Popis M, Kellner S, Hölter SM, Garrett L, Wurst W, Becker L, Klopstock T, Fuchs H, Gailus-Durner V, Hrab? de Angelis M, Káradóttir RT, Helm M, Ule J, Gleeson JG, Odom DT, Frye M (2014), “Aberrant methylation of tRNAs links cellular stress to neuro-developmental disorders.” EMBO J Details

Karadottir RT, Walhovd KB (2014), “The CNS White Matter.” Neuroscience Details

Tyzack GE, Sitnikov S, Barson D, Adams-Carr KL, Lau NK, Kwok JC, Zhao C, Franklin RJ, Karadottir RT, Fawcett JW, Lakatos A (2014), “Astrocyte response to motor neuron injury promotes structural synaptic plasticity via STAT3-regulated TSP-1 expression.” Nat Commun 5:4294 Details

Walhovd KB, Johansen-Berg H, Karadottir RT (2014), “Unraveling the secrets of white matter - Bridging the gap between cellular, animal and human imaging studies.” Neuroscience Details


Agathou S, Káradóttir RT, Kazanis I (2013), “Niche derived oligodendrocyte progenitors: a source of rejuvenation or complementation for local oligodendrogenesis?” Front Cell Neurosci 7:188 Details

Spitzer S, Agathou S, Karadottir RT (2013), “Clever glia.” Stem Cell Res Ther 4(4):100 Details

Stacpoole SR, Spitzer S, Bilican B, Compston A, Karadottir R, Chandran S, Franklin RJ (2013), “High yields of oligodendrocyte lineage cells from human embryonic stem cells at physiological oxygen tensions for evaluation of translational biology.” Stem Cell Reports 1(5):437-50 Details

Tailor J, Kittappa R, Leto K, Gates M, Borel M, Paulsen O, Spitzer S, Karadottir RT, Rossi F, Falk A, Smith A (2013), “Stem cells expanded from the human embryonic hindbrain stably retain regional specification and high neurogenic potency.” J Neurosci 33(30):12407-22 Details


Káradóttir RT, Stockley JH (2012), “Deconstructing myelination: it all comes down to size.” Nat Methods 9(9):883-4 Details


Bakiri Y, Káradóttir R, Cossell L, Attwell D (2011), “Morphological and electrical properties of oligodendrocytes in the white matter of the corpus callosum and cerebellum.” J Physiol 589(Pt 3):559-73 Details

Stacpoole SR, Bilican B, Webber DJ, Luzhynskaya A, He XL, Compston A, Karadottir R, Franklin RJ, Chandran S (2011), “Efficient derivation of NPCs, spinal motor neurons and midbrain dopaminergic neurons from hESCs at 3% oxygen.” Nat Protoc 6(8):1229-40 Details

Stacpoole SR, Bilican B, Webber DJ, Luzhynskaya A, He XL, Compston A, Karadottir R, Franklin RJ, Chandran S (2011), “Derivation of neural precursor cells from human ES cells at 3% O(2) is efficient, enhances survival and presents no barrier to regional specification and functional differentiation.” Cell Death Differ 18(6):1016-23 Details


Christ AF, Franze K, Gautier H, Moshayedi P, Fawcett J, Franklin RJ, Karadottir RT, Guck J (2010), “Mechanical difference between white and gray matter in the rat cerebellum measured by scanning force microscopy.” J Biomech 43(15):2986-92 Details


Bakiri Y, Attwell D, Káradóttir R (2009), “Electrical signalling properties of oligodendrocyte precursor cells.” Neuron Glia Biol 5(1-2):3-11 Details

Bakiri Y, Burzomato V, Frugier G, Hamilton NB, Káradóttir R, Attwell D (2009), “Glutamatergic signaling in the brain's white matter.” Neuroscience 158(1):266-74 Details

Kolodziejczyk K, Hamilton NB, Wade A, Káradóttir R, Attwell D (2009), “The effect of N-acetyl-aspartyl-glutamate and N-acetyl-aspartate on white matter oligodendrocytes.” Brain 132(Pt 6):1496-508 Details


Bakiri Y, Hamilton NB, Káradóttir R, Attwell D (2008), “Testing NMDA receptor block as a therapeutic strategy for reducing ischaemic damage to CNS white matter.” Glia 56(2):233-40 Details


Káradóttir R, Attwell D (2007), “Neurotransmitter receptors in the life and death of oligodendrocytes.” Neuroscience 145(4):1426-38 Details


Pattinson D, Baccei M, Karadottir R, Torsney C, Moss A, McCutcheon J, Giese KP, Fitzgerald M (2006), “Aberrant dendritic branching and sensory inputs in the superficial dorsal horn of mice lacking CaMKIIalpha autophosphorylation.” Mol Cell Neurosci 33(1):88-95 Details


Allen NJ, Káradóttir R, Attwell D (2005), “A preferential role for glycolysis in preventing the anoxic depolarization of rat hippocampal area CA1 pyramidal cells.” J Neurosci 25(4):848-59 Details

Káradóttir R, Cavelier P, Bergersen LH, Attwell D (2005), “NMDA receptors are expressed in oligodendrocytes and activated in ischaemia.” Nature 438(7071):1162-6 Details