JN Miami Valley Hospital
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 97: 1163-1170, 2007. First published December 6, 2006; doi:10.1152/jn.01119.2006
0022-3077/07 $8.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
97/2/1163    most recent
01119.2006v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via ISI Web of Science (3)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Alkondon, M.
Right arrow Articles by Albuquerque, E. X.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Alkondon, M.
Right arrow Articles by Albuquerque, E. X.

Strain-Specific Nicotinic Modulation of Glutamatergic Transmission in the CA1 Field of the Rat Hippocampus: August Copenhagen Irish Versus Sprague-Dawley

Manickavasagom Alkondon1,*, Edna F. R. Pereira1,*, Michelle C. Potter2,3, Frederick C. Kauffman4, Robert Schwarcz1,2 and Edson X. Albuquerque1

1Department of Pharmacology and Experimental Therapeutics; 2Maryland Psychiatric Research Center, University of Maryland School of Medicine; 3Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland; and 4Department of Pharmacology and Toxicology, Rutgers University, Piscataway, New Jersey

Submitted 20 October 2006; accepted in final form 5 December 2006

Prepulse inhibition (PPI), a measure of sensorimotor gating impaired in patients with schizophrenia, is more sensitive to disruption by apomorphine in prepubertal August Copenhagen Irish (ACI) than Sprague-Dawley (SD) rats. In brain regions including the hippocampus, PPI is modulated by {alpha}7* nicotinic receptors (nAChRs) and kynurenic acid (KYNA), a kynurenine metabolite that blocks {alpha}7 nAChRs. Here, KYNA levels and nAChR activities were measured in the hippocampi of 10- to 23-day-old ACI and SD rats of both sexes. Hippocampal KYNA levels were not different between ACI and SD rats. In hippocampal slices from both rat strains, choline (10 mM) evoked {alpha}7* nAChR-mediated type IA currents in CA1 stratum radiatum (SR) interneurons. In the presence of {alpha}7 nAChR antagonists, acetylcholine (ACh, 1 mM) evoked {alpha}4beta2* nAChR-mediated type II currents. ACh also triggered excitatory postsynaptic currents (EPSCs) that resulted from {alpha}3beta4* nAChR activation in glutamatergic neurons/axons synapsing onto the interneurons. The magnitude of the nicotinic responses did not differ significantly between male and female rats. Only the magnitude of {alpha}3beta4* nAChR responses and the frequency of spontaneous EPSCs recorded from CA1 SR interneurons differed between the rat strains, being significantly larger in ACI than SD rats. These results indicate that the {alpha}3beta4* nAChR activity in glutamatergic neurons/axons and the number of glutamatergic terminals synapsing onto CA1 SR interneurons are larger in prepubertal ACI than SD rats. The differential sensitivity of these rats to PPI disruption by apomorphine may result from strain-specific levels of glutamatergic activity and its strain-specific modulation by {alpha}3beta4* nAChRs in the hippocampus.

Address for reprint requests and other correspondence: E. X. Albuquerque, Dept. of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, MD 21201 (E-mail: ealbuque{at}umaryland.edu)






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2007 by the The American Physiological Society.