HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cherubini, E Articles by Williams, J T Search for Related Content PubMed PubMed Citation Articles by Cherubini, E Articles by Williams, J T

Vollum Institute, Oregon Health Sciences University, Portland 97201.

1. Intracellular recordings were made from locus coeruleus neurones in a slice of tissue cut from the rat pons. A depolarizing postsynaptic potential (PSP) followed electrical stimulation of the slice surface; the latency was 1-3 ms and the duration was 50-200 ms. 2. The reversal potential of the PSP (estimated by extrapolation from potentials between -60 and -90 mV) was -27 mV when the recording electrodes contained potassium chloride, and -36 mV when electrodes contained potassium acetate or methylsulphate. 3. Kynurenic acid depressed the PSP amplitude by up to 60%. The residual PSP reversed polarity at -50 mV (extrapolated, potassium chloride in electrodes) or -70 mV (observed, potassium methylsulphate in electrodes): it was blocked by bicuculline (10 microM). 4. Exogenously applied gamma-aminobutyric acid (GABA) depolarized cells when the recording electrode contained potassium chloride (reversal potential was -45 mV) and hyperpolarized cells when the recording electrode contained potassium methylsulphate (reversal potential was -70 mV). 5. In the presence of bicuculline, the residual PSP was blocked by kynurenic acid, whereas DL-2-amino-5-phosphonovaleric acid (2-APV) reduced its amplitude to 80% of control. 6. Exogenously applied glutamate, quisqualate and N-methyl-D-aspartate (NMDA) all caused a membrane depolarization (or an inward current under voltage clamp) which reversed polarity at about 0 mV. These effects were blocked by kynurenic acid (500 microM); 2-APV (50 microM) selectively blocked the effect of NMDA. 7. The results indicate that the PSP evoked by focal stimulation within the nucleus locus coeruleus results from an excitatory amino acid acting predominantly at non-NMDA receptors, and from GABA acting at GABAA receptors.

This article has been cited by other articles:

				Y.-Z. Pan, D.-P. Li, S.-R. Chen, and H.-L. Pan Activation of delta -Opioid Receptors Excites Spinally Projecting Locus Coeruleus Neurons Through Inhibition of GABAergic Inputs J Neurophysiol, November 1, 2002; 88(5): 2675 - 2683. [Abstract] [Full Text] [PDF]

				M. Ishimatsu and J. T. Williams Synchronous Activity in Locus Coeruleus Results from Dendritic Interactions in Pericoerulear Regions J. Neurosci., August 15, 1996; 16(16): 5196 - 5204. [Abstract] [Full Text] [PDF]