Leslie Buck

buck.jpg
Full Professor
Associate Chair, Graduate Studies
Department: 
Cell & Systems Biology
Research Areas: 
Animal Physiology, Neurobiology, Proteomics
Graduate Programs: 
Ecology & Evolutionary Biology
Office phone: 
416-978-3506
Lab phone: 
416-946-7238
Fax: 
416-978-8532
Office: 
RW 329

les [dot] buck (at)utoronto [dot] ca

Address: 

Department of Cell & Systems Biology
University of Toronto
25 Harbord Street, RW 329
Toronto, Ontario
Canada M5S 3G5

Research: 

Our primary interest is understanding what makes some animal species tolerant to severe hypoxia and others intolerant. Of particular interest are the underlying cellular mechanisms that effectively reduce cellular energetic demands (in terms of ATP utilization) with the onset of hypoxia. Key to surviving long term severe hypoxia is the ability to reduce cellular ATP utilization. One major site of ATP utilization for all cells is the maintenance of cellular ion gradients, the loss of gradients being one hallmark of hypoxic cell injury. Using a brain sheet and hepatocyte preparation from the western painted turtle, the most hypoxia tolerant vertebrate known, we are studying the second messenger pathways regulating hypoxic suppression of brain glutamate receptor and liver Na+ /K+ ATPase, both of which we have previously demonstrated to be actively down-regulated in hypoxia. We are also interested in the suite of proteins expressed in hypoxically preconditioned mammalian tissues. One of these (HSP 70) we have detected at the mRNA level in hypoxically stressed turtle hepatocytes. We are currently investigating the role of adenosine in the hypoxic expression of HSP 70. A better understanding of these mechanisms may lead to improved clinical interventions where hypoxia is life threatening.

2013
Rodgers-Garlick, C. I, Hogg, D.W., Buck, L.T. (2013).  Oxygen-Sensitive Reduction in Ca2+-activated K+ channel open probability in turtle cerebrocortex. Neuroscience. 237, 243-254.
Buck, L.T., Warren, D., many,, others, (2013).  The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage. Genome Biology. 14(R28), doi:10.1186/gb-2013-14-3-r28.
Hawrysh, P., Buck, L. (2013).  Anoxia-mediated calcium release through the mitochondrial permeability transition pore silences NMDA receptor currents in turtle neurons. Journal of Experimental Biology. 216, 4375-4387.
2012
Pamenter, M.E., Hogg, D.W., Gu, X.Q., Buck, L.T., Haddad, G.G. (2012).  Anoxia-tolerant Western Painted turtle cortex is resistant to an in vitro mimic of the ischemic mammalian penumbra. J. Cereb. Blood Flow and Metab. 32(11), 2033-43.
Buck, L.T., Hogg, D.W.R., Rodgers-Garlick, C. I, Pamenter, M.E. (2012).  Oxygen sensitive synaptic neurotransmission in anoxia-tolerant turtle cerebrocortex. Arterial Chemoreception. Advances in Experimental Medicine and Biology. 758, 71 - 79.
2011
Pamenter, M.E., Ormond, J., Hogg, D.W., Woodin, M., Buck, L.T. (2011).  Endogenous GABAA and GABAB receptor-mediated electrical suppression is critical to neuronal anoxia tolerance. Proceedings of the National Academy of Sciences, USA. 108(27), 11274-11279.
2010
Malik, A., Buck, L.T. (2010).  Adenosine-mediated neuronal depression in the pond snail Lymnaea stagnalis. Journal of Experimental Biology. 213, 1126-1132.
Zivkovic, G., Buck, L.T. (2010).  Mitochondrial ATP sensitive K+ channels decrease AMPAR currents in the anoxic turtle cortex. Journal of Neurophysiology. 104, 1913-1922.
2009
Zhang, Z., Smit, G., N.,, Syed,, van S, V.R.K., Fainzilber, M., Goldberg, J.I., Spencer, G., Yeoman, M., Wildering, W., Coorssen, J.R., Croll, R., Buck, L.T., Feng, Z-P. (2009).  Transcriptome analysis of the central nervous system of the mollusc Lymnaea stagnalis. BMC Genomics. 23(10), 451.
2008
Pamenter, M.E., Buck, L.T. (2008).  Delta-opiod receptor antagonism potentiates N-methyl-D-aspartate receptor currents and induces extended neuronal depolarization in anoxic turtle cortex. J. Exp. Biol. 211, 3512-3527.
Pamenter, M.E., Buck, L.T. (2008).  Neuronal membrane potential is mildly depolarized in the anoxic turtle cortex. Comp Biochem. Physiol. A. 150, 410-414.
Pamenter, M.E., Buck, L.T. (2008).  Endogenous reductions in N-methyl-D-aspartate receptor activity inhibit nitric oxide production in the anoxic freshwater turtle cortex. FEBS Lett. 582, 1738-1742.
Pamenter, M.E., Shin, D.S-H., Buck, L.T. (2008).  AMPA receptors undergo channel arrest in the anoxic turtle cortex. Am. J. Physiol. Regul. Integr. Comp. Physiol. 294(2), R606-613.
Pamenter, M.E., S-H., S.D., Cooray, M., L.T., B. (2008).  Mitochondrial KATP channels mediate anoxia-induced decreases in NMDAR activity in the turtle cortex. J. Physiol. 586(4), 1043-1058.
2007
Walsh, P., Veauvey, C., Pamenter, M., Buck, L., Wilkie, M. (2007).  Piscine insights into comparisons of anoxia tolerance, ammonia toxicity, stroke and hepatic encephalopathy. Comp. Biochem. Phys. A. 147, 332-343.
Pamenter, M.E., Richards, M., Buck, L.T. (2007).  Anoxia-induced changes in second messengers and reactive oxygen species in the painted turtle. J. Comp. Physiol. B. 177(4), 473-481.
Bickler, P.E., Buck, L.T. (2007).  Hypoxia tolerance in reptiles, amphibians and fishes: life with variable oxygen availability. Annu. Rev. Physiol. 69, 5.1-5.26.
2006
Buck, L., Pamenter, M. (2006).  Adaptive responses of vertebrate neurons to hypoxia, Matching supply to demand. Resp. Physiol. Neurobiol. 154, 226-240.
Cheung, U., Mogashi, M., Smith, J., Buck, L., Woodin, M. (2006).  Excitatory actions of GABA mediate severe-hypoxia induced depression of neuronal activity in the pond snail (Lymnaea stagnalis). J. Exp. Biol. 209, 4429-4435.
2005
Shin, D., Wilkie, M., Pamenter, M., Buck, L. (2005).  Calcium and protein phosphatase 1/2A attenuate N-methyl-D-aspartate receptor activity in the anoxic turtle cortex. Comp. Biochem. Physiol. (A) 142, 50-57.
2004
Ramaglia, V., Harapa, G., White, N., Buck, L. (2004).  Bacterial Infection Induces Heat Shock Protein Expression in the Western Painted Turtle.. Comp. Biochem. Physiol. Part C.. 138(2), 139-148.
Ramaglia, V., Buck, L. (2004).  Tissue specific expression of inducible and constitutive Hsp70 isoforms and Hsp90 in the western painted turtle.. J. Exp. Biol.. 207(21), 3775-3784.
Buck, L. (2004).  Adenosine as a Signal for Ion Channel Arrest in Anoxia-Tolerant Organisms.. Comp. Biochem. Physiol. B.. 139(3), 401-414.
2003
Scott, M., Locke, M., Buck, L. (2003).  Tissue-specific expression of inducible and constitutive Hsp70 isoforms in the western painted turtle.. J. Exp. Biol.. 206, 303-311.
Buck, L., Shin, D. (2003).  Role of adenosine in the natural anoxia-tolerance of the freshwater turtle.. Trends in Comparative Biochemistry and Physiology Vol.. 9, 93-116.
Shin, D., Ghai, H., Cain, S., Buck, L. (2003).  Gap junctions do not underlie changes in whole-cell conductance in the anoxic turtle brain.. Comp. Biochem. Physiol.. Part A, 13, 181-194.
Shin, D., Buck, L. (2003).  Effect of anoxia and pharmacological anoxia on whole-cell NMDA receptor currents in cortical neurons from the western painted turtle.. Physiol. Biochem. Zool.. 76(2), 532-543.
2002
Bickler, P., Buck, L. (2002).  Molecular adaptations for survival during anoxia: lessons from lower vertebrates.. The Neuroscientist. 8(3), 234-242.
2000
Bickler, P., Donohoe, P., Buck, L. (2000).  Hypoxia-induced silencing of N-methyl-D aspartate receptors in turtle neurons.. J. Neuroscience. 20(10), 3522-3528.
Buck, L. (2000).  Importance of succinate as an anaerobic endproduct in the diving turtle (Chrysemys picta bellii).. Comp. Biochem. Physiol. Part B. 126, 409-413.
1996
Hochachka, P., Buck, L., Doll, C., Land, S. (1996).  Unifying theory of hypoxia tolerance: molecular/metabolic defense and rescue mechanisms for surviving oxygen lack.. Proceed. Nat. Acad. Sci. USA. 1996 Sept., 9493-9498.