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VINCENT A. CHIAPPINELLI, PH.D. The Ralph E. Loewy Professor Chair of the Department of Pharmacology & Physiology Professor of Neurological Surgery Contact Information Affiliation Education Members of the lab and collaborators Research Description Short Description of Research Laboratory web site Active Grant Information Recent Publications |
CONTACT INFORMATION
The George Washington University
Department of Pharmacology & Physiology
2300 Eye Street NW, Suite 640
Washington, D.C. 20037
E-mail: phmvac@gwumc.edu
Voice: (202) 994-3541
Fax: (202) 994-2870
AFFILIATION
Member of Molecular Medicine Program, Institute for Biomedical Sciences
Ph.D. in Molecular Medicine
Pharmacogenomics Program
EDUCATION
Ph.D. in Neuropharmacology, 1977. University of Connecticut
MEMBERS OF THE LAB
Dr. Eva Sorenson
Dr. Jian-Zhong Guo
RESEARCH DESCRIPTION
Nicotinic Acetylcholine Receptor Function in the Brain. We use whole cell and single channel patch clamp electrophysiology, combined with immunohistochemistry and autoradiography, to understand the functional roles of nicotinic receptors in the central nervous system. Two distinct effects of nicotinic receptor activation are observed. Postsynaptic nicotinic receptors produce marked excitation of certain neurons due to depolarization. In contrast, presynaptic and preterminal nicotinic receptors, located on or near nerve terminals, enhance the release of the neurotransmitters GABA and glutamate. Thus, central nicotinic receptors perform important modulatory functions in neurotransmission at many types of synapses, and we are continuing to refine our understanding of their roles in this process.
Effects of Chronic Nicotine During Development. It is known that maternal cigarette smoking during pregnancy produces a number of changes in human fetal development, including reduced fetal weight and behavioral alterations after birth. Since cigarette smoke contains numerous toxic substances in addition to nicotine, the specific effects of fetal exposure to nicotine remain to be determined. We have found that in the chick embryo, chronic nicotine produces a marked up-regulation of certain subtypes of nicotinic receptors in the brain. We have begun to identify and quantify the functional consequences of these alterations in receptor number.
Electrophysiology of Presynaptic Nerve Terminals. The chick ciliary ganglion contains specialized structures termed calyciform nerve terminals which, due to their unusually large size, allow us to obtain direct physiological recordings from terminal regions. Using whole-cell patch clamp and intracellular recording techniques, we are using this model system of presynaptic terminal function to identify physiologically relevant ion channels and receptors present on nerve terminals.
SHORT DESCRIPTION OF RESEARCH
Patch clamp electrophysiology; nicotinic receptors and presynaptic nerve terminals
DR. VINCENT A. CHIAPPINELLI'S LABORATORY WEB SITE
ACTIVE GRANT INFORMATION
National Institute of Neurological Disorders and Stroke, National Institutes of Health. Research Award NS17574-22, "Functional Properties of Neuronal Nicotinic Receptors." Sixth Renewal, 1/22/07 -11/30/2010, $875,000 - direct costs. Principal Investigator.
SELECTED RECENT PUBLICATIONS
Guo, J.-Z., T.L. Tredway and V.A. Chiappinelli (1998). Glutamate and GABA release are enhanced by different subtypes of presynaptic nicotinic receptors in the lateral geniculate nucleus. J. Neuroscience 18, 1963-1969.
Tredway, T.L., J.-Z. Guo and V.A. Chiappinelli (1999). N-Type calcium channels mediate the nicotinic enhancement of GABA release. J. Neurophysiology 81, 447-454.
Nong, Y., E.M. Sorenson and V.A. Chiappinelli (1999). Fast excitatory nicotinic transmission in the chick lateral spiriform nucleus. J. Neuroscience 19, 7804-7811.
Zhu, P.J. and V.A. Chiappinelli (1999). Nicotine modulates evoked GABAergic transmission in the brain. J. Neurophysiology 82, 3041-3045.
Sorenson, E.M., D.G. El-Bogdadi, Y. Nong and V.A. Chiappinelli (2001). Alpha7-containing nicotinic receptors are segregated to the somatodendritic membrane of the cholinergic neurons in the avian nucleus semilunaris. Neuroscience 103, 541-550.
Guo, J.-Z. and V.A. Chiappinelli (2002). A novel choline-sensitive nicotinic receptor subtype that mediates enhanced GABA release in the chick ventral lateral geniculate nucleus. Neuroscience 110,505-513.
Zhu, P.J. and V.A. Chiappinelli (2002). Nicotinic receptors mediate increased GABA release in brain through a tetrodotoxin-insensitive mechanism during prolonged exposure to nicotine. Neuroscience 115, 137-144.
Nong, Y., E.M. Sorenson and V.A. Chiappinelli (2003). Opioid receptor activation attenuates nicotinic enhancement of spontaneous GABA release in lateral spiriform nucleus of the chick. Brain Research 961, 45-52.
Guo, J.-Z., Y. Liu, E.M. Sorenson and V.A. Chiappinelli (2005). Synaptically released and exogenous ACh activates different nicotinic receptors to enhance evoked glutamatergic transmission in the lateral geniculate nucleus. Journal of Neurophysiology 94,2549-2560.
Liu, Y.-B., J.-Z. Guo and V. A. Chiappinelli ( 2007). Nicotinic receptor-mediated biphasic effect on neuronal excitability in chick lateral spiriform neurons. Neuroscience 148, 1004-1014.