Loren Martin
Assistant Professor
Campus
UTM
CSB Appointment
Full
Research Areas
Molecular Biology, Neurobiology, Physiology
Education
Ph.D., University of Toronto, 2009
Primary Undergraduate Department
Psychology
Graduate Programs
Psychology
Cell & Systems Biology
Neuroscience
Research Description
The research in my laboratory aims to understand how painful experiences modify the neural circuits and transmitter/peptide systems related to sensory, emotional, social and cognitive information. Bringing together mouse genetics, electrophysiology, viral tracing, pharmaco- and optogenetics we study the functional interrogation of these circuits within brain and spinal pathways. Our data and the data of others suggests that chronic pain alters synaptic transmission within distinct neural networks and resultant behavioural modifications are dependent upon where in the brain these changes occur. This has led us to investigate the modulation of these circuits by neuropeptides such as oxytocin and opioids to understand their involvement in pain empathy, social approach/avoidance and social analgesia. In a separate line of research, we use novel approaches to understand the learning mechanisms associated with the development of pain and anxiety as well as pain relief. If we are able to understand the processes by which these different functional dimensions of pain perceptions are generated and modified, in particular the circuits encoding negative affective states, then new dynamic frameworks for treating unrelenting chronic pain may be developed.
Contact Information
Office Phone: 905-569-5784
Office: CCT4061
Lab: DV-1076
Lab Phone: 905-828-3785
Email
Mailing Address
Department of Cell & Systems Biology
University of Toronto
3359 Mississauga Road
Mississauga, ON L5L 1C6
Canada
Publications
2015
Molecular genetic mechanisms of allelic specific regulation of murine Comt expression
Segall SK, Shabalina SA, Meloto CB, Wen X, Cunningham D, Tarantino LM, Wiltshire T, Gauthier J, Tohyama S, Martin LJ, Mogil JS, Diatchenko L
2015, Pain, 156, 1965-77, 26067582
Different immune cells mediate mechanical pain hypersensitivity in male and female mice
Sorge RE, Mapplebeck JC, Rosen S, Beggs S, Taves S, Alexander JK, Martin LJ, Austin JS, Sotocinal SG, Chen D, Yang M, Shi XQ, Huang H, Pillon NJ, Bilan PJ, Tu Y, Klip A, Ji RR, Zhang J, Salter MW, Mogil JS
2015, Nature neuroscience, 18, 1081-3, 26120961
The nicotinic α6 subunit gene determines variability in chronic pain sensitivity via cross-inhibition of P2X2/3 receptors
Wieskopf JS, Mathur J, Limapichat W, Post MR, Al-Qazzaz M, Sorge RE, Martin LJ, Zaykin DV, Smith SB, Freitas K, Austin JS, Dai F, Zhang J, Marcovitz J, Tuttle AH, Slepian PM, Clarke S, Drenan RM, Janes J, Al Sharari S, Segall SK, Aasvang EK, Lai W, Bittner R, Richards CI, Slade GD, Kehlet H, Walker J, Maskos U, Changeux JP, Devor M, Maixner W, Diatchenko L, Belfer I, Dougherty DA, Su AI, Lummis SC, Imad Damaj M, Lester HA, Patapoutian A, Mogil JS
2015, Science translational medicine, 7, 287ra72, 25972004
Reducing social stress elicits emotional contagion of pain in mouse and human strangers
Martin LJ, Hathaway G, Isbester K, Mirali S, Acland EL, Niederstrasser N, Slepian PM, Trost Z, Bartz JA, Sapolsky RM, Sternberg WF, Levitin DJ, Mogil JS
2015, Current biology : CB, 25, 326-32, 25601547
2014
Olfactory exposure to males, including men, causes stress and related analgesia in rodents
Sorge RE, Martin LJ, Isbester KA, Sotocinal SG, Rosen S, Tuttle AH, Wieskopf JS, Acland EL, Dokova A, Kadoura B, Leger P, Mapplebeck JC, McPhail M, Delaney A, Wigerblad G, Schumann AP, Quinn T, Frasnelli J, Svensson CI, Sternberg WF, Mogil JS
2014, Nature methods, 11, 629-32, 24776635
The interaction between pain and social behavior in humans and rodents
Martin LJ, Tuttle AH, Mogil JS
2014, Current topics in behavioral neurosciences, 20, 233-50, 24557935
2013
Acutely increasing δGABA(A) receptor activity impairs memory and inhibits synaptic plasticity in the hippocampus
Whissell PD, Eng D, Lecker I, Martin LJ, Wang DS, Orser BA
2013, Frontiers in neural circuits, 7, 146, 24062648
2011
The Rat Grimace Scale: a partially automated method for quantifying pain in the laboratory rat via facial expressions
Sotocinal SG, Sorge RE, Zaloum A, Tuttle AH, Martin LJ, Wieskopf JS, Mapplebeck JC, Wei P, Zhan S, Zhang S, McDougall JJ, King OD, Mogil JS
2011, Molecular pain, 7, 55, 21801409
2010
The sedative but not the memory-blocking properties of ethanol are modulated by α5-subunit-containing γ-aminobutyric acid type A receptors
Martin LJ, Zurek AA, Bonin RP, Oh GH, Kim JH, Mount HT, Orser BA
2011, Behavioural brain research, 217, 379-85, 21070817
Short-term memory impairment after isoflurane in mice is prevented by the α5 γ-aminobutyric acid type A receptor inverse agonist L-655,708
Saab BJ, Maclean AJ, Kanisek M, Zurek AA, Martin LJ, Roder JC, Orser BA
2010, Anesthesiology, 113, 1061-71, 20966663
Alpha5GABAA receptor activity sets the threshold for long-term potentiation and constrains hippocampus-dependent memory
Martin LJ, Zurek AA, MacDonald JF, Roder JC, Jackson MF, Orser BA
2010, The Journal of neuroscience : the official journal of the Society for Neuroscience, 30, 5269-82, 20392949
2009
The physiological properties and therapeutic potential of alpha5-GABAA receptors
Martin LJ, Bonin RP, Orser BA
2009, Biochemical Society transactions, 37, 1334-7, 19909271
alpha5 Subunit-containing GABA(A) receptors mediate a slowly decaying inhibitory synaptic current in CA1 pyramidal neurons following Schaffer collateral activation
Vargas-Caballero M, Martin LJ, Salter MW, Orser BA, Paulsen O
2010, Neuropharmacology, 58, 668-75, 19941877
Etomidate targets alpha5 gamma-aminobutyric acid subtype A receptors to regulate synaptic plasticity and memory blockade
Martin LJ, Oh GH, Orser BA
2009, Anesthesiology, 111, 1025-35, 19809285
Suppression of hippocampal TRPM7 protein prevents delayed neuronal death in brain ischemia
Sun HS, Jackson MF, Martin LJ, Jansen K, Teves L, Cui H, Kiyonaka S, Mori Y, Jones M, Forder JP, Golde TE, Orser BA, Macdonald JF, Tymianski M
2009, Nature neuroscience, 12, 1300-7, 19734892
2007
Alpha5GABAA receptors regulate the intrinsic excitability of mouse hippocampal pyramidal neurons
Bonin RP, Martin LJ, MacDonald JF, Orser BA
2007, Journal of neurophysiology, 98, 2244-54, 17715197
2006
Alpha5GABAA receptors mediate the amnestic but not sedative-hypnotic effects of the general anesthetic etomidate
Cheng VY, Martin LJ, Elliott EM, Kim JH, Mount HT, Taverna FA, Roder JC, Macdonald JF, Bhambri A, Collinson N, Wafford KA, Orser BA
2006, The Journal of neuroscience : the official journal of the Society for Neuroscience, 26, 3713-20, 16597725
2005
Modulation of NMDA receptors by pituitary adenylate cyclase activating peptide in CA1 neurons requires G alpha q, protein kinase C, and activation of Src
Macdonald DS, Weerapura M, Beazely MA, Martin L, Czerwinski W, Roder JC, Orser BA, MacDonald JF
2005, The Journal of neuroscience : the official journal of the Society for Neuroscience, 25, 11374-84, 16339032
2004
Influence of a complex magnetic field application in rats upon thermal nociceptive thresholds: the importance of polarity and timing
Martin LJ, Koren SA, Persinger MA
2004, The International journal of neuroscience, 114, 1259-76, 15370185
Alpha2-adrenergic inhibition prevents the accompanied anticonvulsant effect of swim stress on behavioral convulsions induced by lithium and pilocarpine
Galic MA, Fournier NM, Martin LJ
2004, Pharmacology, biochemistry, and behavior, 79, 309-16, 15501307
Thermal analgesia induced by 30-min exposure to 1 microT burst-firing magnetic fields is strongly enhanced in a dose-dependent manner by the alpha2 agonist clonidine in rats
Martin LJ, Persinger MA
2004, Neuroscience letters, 366, 226-9, 15276252
Thermal analgesic effects from weak, complex magnetic fields and pharmacological interactions
Martin LJ, Koren SA, Persinger MA
2004, Pharmacology, biochemistry, and behavior, 78, 217-27, 15219761
Chronic administration of the L-type calcium channel blocker nimodipine can facilitate the acquisition of sequence learning in a radial-arm maze
Martin LJ, Fournier NM, Galic MA, Emond MH
2004, Behavioural pharmacology, 15, 133-9, 15096913
2003
Spatial heterogeneity not homogeneity of the magnetic field during exposures to complex frequency-modulated patterns facilitates analgesia
Martin LJ, Persinger MA
2003, Perceptual and motor skills, 96, 1005-12, 12831282