Margarita C. Currás-Collazo

Associate Professor of Cell Biology & Neuroscience
Email: mcur@ucrac1.ucr.edu


B.S., 1982, Biology and Psychology with Honors
Tulane University

Ph.D., 1989, Physiology
The Ohio State University, 1989

Postdoctoral, 1989-92
University of North Carolina at Chapel Hill
(American Epilepsy Society Research Fellow 1990-92)

Postdoctoral, 1992-93
NRSA Postdoctoral Fellowship
Emory University

Interests: Neuroendocrinology and medical neuroscience. Specialty areas: neural control of hydromineral balance, autoregulation of magnocellular neuroendocrine cells by vasopressin and actions of endocrine disruptors; mechanisms underlying excitotoxicity and neuroprotection in neurotrauma and stroke injury models.

One main focus of our research is autocontrol of neuroendocrine cells of the supraoptic nucleus of the rat hypothalamus (SON) which produce vasopressin (VP) and oxytocin (OXY), hormones involved in osmoregulation, lactation and parturition as well as cardiovascular function. A recent finding from our lab, modulation of stimulated glutamate release by VP and OXY, suggests that locally released OXY and VP may autoregulate SON activity, in part, by modulating the release of excitatory amino acids from afferent terminals targeting these cells. We are investigating the physiological significance of dendritic signaling by VP and the mechanisms underlying dendritic release of VP including the actions of nitric oxide, VP autoreceptors, pituitary adenylate cyclase activating peptide (PACAP) and glutamate receptors. We have recently discovered a novel role of intra-SON PACAP in controlling VP release stimulated by osmotic activation. Studies are underway that examine the receptor subtypes and signal transduction processes involved in PACAP control over VP release. Other projects examine the mechanisms underlying disruption of osmoregulation and other neuroendocrine processes by the environmental toxins, persistent organic pollutants such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs).

Other studies aim to identify neuroprotective mechanisms relevant to SON viability (these cells are less susceptible to excitotoxic injury (in vitro) and ischemic neuronal death (in vivo) relative to cortical and other central neurons. Our lab has shown that resistance to glutamate-evoked excitotoxicity may be associated with a greater capacity for glutamate clearance and more efficient calcium extrusion and free radical scavenging. In collaboration with investigators at Loma Linda University we have been using brain imaging to describe evolution of brain damage and to predict outcome. More recently, we have been using stem cells to alleviate adverse effects of neurotrauma and other injuries. Our findings may lead eventually to the development of alternative therapies for stroke and neurodegenerative diseases.

Selected Publications

• Currás, M. C. and J. A. Boulant. Effects of ouabain on neuronal thermosensitivity in hypothalamic tissue slices.  American Journal of Physiology 257:R21-R28, 1989.

• Currás, M. C., S. R. Kelso, and J. A. Boulant.  Intracellular analysis of inherent and synaptic activity in hypothalamic thermosensitive neurones in the rat.  Journal of Physiology 440:257-271, 1991.

• Currás, M. C. and R. J. Dingledine.  Selectivity of amino acid transmitters acting at  NMDA and AMPA receptors.  Molecular Pharmacology 41:520-526, 1992.

• Currás, M. C. and B. S. Pallotta.  Single-channel evidence for glycine and NMDA requirement in NMDA receptor activation.  Brain Research 740:27-40, 1996.

• Decavel, C. and M. C. Currás.  Increased expression of the NMDA receptor subunit, NR1, in immunohistochemically identified magnocellular hypothalamic neurons during dehydration.  Neuroscience 78(1):191-202, 1997.

• Currás, M. C., P. Rack and R. B. Meeker.  Channel properties of NMDA glutamate  receptors on magnocellular neuroendocrine cells cultured from the rat supraoptic nucleus.  Brain Research 789:181-193, 1998.  (cover article)

• Meeker, R. B., M. C. Currás, J. Stewart, A. Serje and W. Al-Ghoul.  Functional activation of punch-cultured magnocellular neuroendocrine cells by glutamate receptor subtypes.  Journal of Neuroscience Methods 89:57-67, 1999.

• Currás-Collazo, M.C., C. Chin, G. Diaz, C. Stivers, L. Bozzetti and L. Y. Tran.  Immunolabeling reveals cellular localization of the NMDA receptor subunit, NR2B, in neurosecretory cells but not astrocytes of the rat magnocellular nuclei.  Journal of Comparative Neurology, 427(1):93-108, 2000.

• Currás-Collazo, M.C., U. Patel and M. O. Hussein. Reduced susceptibility of rat magnocellular neuroendocrine nuclei to transient focal ischemia produced by middle cerebral artery occlusion.  Experimental Neurology 178(2): 268-279, 2002.

• Coburn, C.G., Gillard, E.R. and M.C. Currás-Collazo. Dietary exposure to Aroclor 1254 alters central and peripheral vasopressin release in response to dehydration in the rat. Toxicological Sciences 84 (1):149-56, Mar 2005

• Qiu, S., Pak, C.-W. and M.C. Currás-Collazo. Sequential involvement of distinct glutamate receptors in domoic acid-induced neurotoxicity in rat mixed cortical cultures: effect of multiple dose/duration paradigms, chronological age and repeated exposure.  Toxicological Sciences 89(1):243-56, 2006.

• Gillard, E.R., M. Leon-Olea, S. Mucio-Ramirez, C. Coburn, A. DeLeon, H. Mussenden, L. Bauce, Q. Pittman, and M. C. Currįs-Collazo. A novel role for endogenous pituitary adenylate cyclase activating polypeptide in the magnocellular neuroendocrine system. Endocrinology 147(2):791-803, 2006.

• Gillard, E.R., Coburn, C.G., de Leon, A., Snissarenko, E.P., Bauce, L.G., Pittman, Q.J., Hou, B. and M.C. Currįs-Collazo. Vasopressin autoreceptors and nitric oxide-dependent glutamate release are required for somatodendritic vasopressin release from rat magnocellular neuroendpcrine cells responding to osmotic stimuli. Endocrinology 148(2):479-89, 2007.

• Obenaus, A., Galloway, N., Robbins, M., Blanco, G., Snissarenko, E., Gillard, E., Lee, S. and M. Curras-Collazo. Multi-modal resonance imaging alterations in two rat models of mild neurotrauma. J Neurotrauma. 24(7):1147-60, 2007.

• Coburn, C.G., Currįs-Collazo, M.C. and P. R. S. Kodavanti. Polybrominated Diphenyl Ethers (PBDEs) and Ortho-substituted Polychlorinated Biphenyls (PCBs) as Neuroendocrine Disruptors of Vasopressin Release: Effects during Physiological Activation in vitro and Structure-Activity Relationships. Toxicol. Sci. 98(1): 178-186, 2007

• Coburn, C.G., Currįs-Collazo, M.C. and P. R. S. Kodavanti. In Vitro Effects of Environmentally Relevant Polybrominated Diphenyl Ether (PBDE) Congeners on Calcium Buffering Mechanisms in Rat Brain. Neurochem Res. 2007 Sep 1; [Epub ahead of print]

• Qiu, S., Jebelli, A.K., Ashe, J. H. and Currįs-Collazo, M.C. Domoic acid induces a long-lasting enhancement of CA1 field responses and impairs tetanus-induced long-term potentiation in rat hippocampal slices. Toxicol. Sci. 2009 Sept; 111(1):140-50. Epub 2009 June 29. PMID: 19564213 [PubMed - in process]

• Qiu, S. and Currįs-Collazo, M.C. Histopathological and molecular changes produced by hippocampal microinjection of domoic acid. Neurotoxicol. Teratol. 2006 May-Jun;28(3):354-62. Epub 2006 Mar 9. PMID: 16529907 [PubMed - indexed for MEDLINE]

• Qiu, S., Pak, C. W. and Currįs-Collazo, M.C. Sequential involvement of distinct glutamate receptors in domoic acid-induced neurotoxicity in rat mixed cortical cultures: effect of multiple dose/duration paradigms, chronological age, and repeated exposure. Toxicol. Sci. 2006 Jan;89(1):243-56. Epub 2005 Oct 12. PMID: 16221958 [PubMed - indexed for MEDLINE].