Publication Date:
1993-08-20
Description:
The effectiveness of long-term potentiation (LTP) as a mechanism for information storage would be severely limited if processes that decrease synaptic strength did not also exist. In area CA1 of the rat hippocampus, prolonged periods of low-frequency afferent stimulation elicit a long-term depression (LTD) that is specific to the stimulated input. The induction of LTD was blocked by the extracellular application of okadaic acid or calyculin A, two inhibitors of protein phosphatases 1 and 2A. The loading of CA1 cells with microcystin LR, a membrane-impermeable protein phosphatase inhibitor, or calmodulin antagonists also blocked or attenuated LTD. The application of calyculin A after the induction of LTD reversed the synaptic depression, suggesting that phosphatase activity is required for the maintenance of LTD. These findings indicate that the synaptic activation of protein phosphatases plays an important role in the regulation of synaptic transmission.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mulkey, R M -- Herron, C E -- Malenka, R C -- MH00942/MH/NIMH NIH HHS/ -- MH10306/MH/NIMH NIH HHS/ -- MH45334/MH/NIMH NIH HHS/ -- New York, N.Y. -- Science. 1993 Aug 20;261(5124):1051-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Psychiatry, University of California, San Francisco 94143-0984.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8394601" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Calcium/metabolism
;
Calmodulin/metabolism
;
Electric Stimulation
;
Ethers, Cyclic/pharmacology
;
Hippocampus/drug effects/enzymology/*physiology
;
Microcystins
;
Okadaic Acid
;
Oxazoles/pharmacology
;
Peptides, Cyclic/pharmacology
;
Phosphoprotein Phosphatases/antagonists & inhibitors/*metabolism
;
Phosphorylation
;
Rats
;
Rats, Sprague-Dawley
;
Receptors, N-Methyl-D-Aspartate/physiology
;
Synapses/drug effects/*physiology
;
*Synaptic Transmission/drug effects
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics