Abstract
1. Hippocampal long-term potentiation (LTP) may serve as an elementary process underlying certain forms of learning and memory in vertebrates. As is the case with behavioural memory, hippocampal LTP in the rat CA1 region and in the dentate gyrus occurs in stages, which can be separated by an inhibitor of RNA synthesis. 2. Experiments have been performed in two brain regions, in the hippocampal CA1 region in vitro and in the dentate gyrus in vivo. 3. Maintenance of hippocampal LTP in the CA1 region in vitro was influenced by the RNA synthesis inhibitor actinomycin D from 4 h onwards. 4. The effect of actinomycin D on the time course of the population spike potentiation was more pronounced than the effect on the time course of the EPSP component, suggesting different mechanisms for the two forms of potentiation. 5. Intrahippocampal and intracerebroventricular injection of actinomycin D into rats prevented a late stage of LTP in the dentate gyrus in vivo measured as the population spike amplitude. 6. Since actinomycin D was only effective in influencing the maintenance of LTP when applied before tetanization, the requirement for transcription during LTP may have a critical time window. 7. Actinomycin D influenced the maintenance of LTP specifically, since the drug did not alter any potentials in control experiments after its removal or when it was administered shortly after tetanization. A second, structurally different RNA synthesis inhibitor, 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole, mimicked the effect of actinomycin D in vitro.
Full text
PDF








Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Abraham W. C., Dragunow M., Tate W. P. The role of immediate early genes in the stabilization of long-term potentiation. Mol Neurobiol. 1991;5(2-4):297–314. doi: 10.1007/BF02935553. [DOI] [PubMed] [Google Scholar]
- Alkon D. L., Amaral D. G., Bear M. F., Black J., Carew T. J., Cohen N. J., Disterhoft J. F., Eichenbaum H., Golski S., Gorman L. K. Learning and memory. FESN Study Group. Brain Res Brain Res Rev. 1991 May-Aug;16(2):193–220. doi: 10.1016/0165-0173(91)90005-s. [DOI] [PubMed] [Google Scholar]
- Bliss T. V., Collingridge G. L. A synaptic model of memory: long-term potentiation in the hippocampus. Nature. 1993 Jan 7;361(6407):31–39. doi: 10.1038/361031a0. [DOI] [PubMed] [Google Scholar]
- Chinestra P., Leinekugel X., Ben Ari Y., Pollard H. Use of hippocampal slices to study mRNA changes in relation to synaptic plasticity. Neuroreport. 1994 Jul 21;5(12):1461–1465. doi: 10.1097/00001756-199407000-00013. [DOI] [PubMed] [Google Scholar]
- Cole A. J., Saffen D. W., Baraban J. M., Worley P. F. Rapid increase of an immediate early gene messenger RNA in hippocampal neurons by synaptic NMDA receptor activation. Nature. 1989 Aug 10;340(6233):474–476. doi: 10.1038/340474a0. [DOI] [PubMed] [Google Scholar]
- Daniels D. Effects of actinomycin D on memory and brain RNA synthesis in an appetitive learning task. Nature. 1971 Jun 11;231(5302):395–397. doi: 10.1038/231395a0. [DOI] [PubMed] [Google Scholar]
- Demmer J., Dragunow M., Lawlor P. A., Mason S. E., Leah J. D., Abraham W. C., Tate W. P. Differential expression of immediate early genes after hippocampal long-term potentiation in awake rats. Brain Res Mol Brain Res. 1993 Mar;17(3-4):279–286. doi: 10.1016/0169-328x(93)90012-e. [DOI] [PubMed] [Google Scholar]
- Dragunow M., Abraham W. C., Goulding M., Mason S. E., Robertson H. A., Faull R. L. Long-term potentiation and the induction of c-fos mRNA and proteins in the dentate gyrus of unanesthetized rats. Neurosci Lett. 1989 Jul 3;101(3):274–280. doi: 10.1016/0304-3940(89)90545-4. [DOI] [PubMed] [Google Scholar]
- Fazeli M. S., Corbet J., Dunn M. J., Dolphin A. C., Bliss T. V. Changes in protein synthesis accompanying long-term potentiation in the dentate gyrus in vivo. J Neurosci. 1993 Apr;13(4):1346–1353. doi: 10.1523/JNEUROSCI.13-04-01346.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frey U., Huang Y. Y., Kandel E. R. Effects of cAMP simulate a late stage of LTP in hippocampal CA1 neurons. Science. 1993 Jun 11;260(5114):1661–1664. doi: 10.1126/science.8389057. [DOI] [PubMed] [Google Scholar]
- Frey U., Krug M., Reymann K. G., Matthies H. Anisomycin, an inhibitor of protein synthesis, blocks late phases of LTP phenomena in the hippocampal CA1 region in vitro. Brain Res. 1988 Jun 14;452(1-2):57–65. doi: 10.1016/0006-8993(88)90008-x. [DOI] [PubMed] [Google Scholar]
- Gilbert M. E., Mack C. M. The NMDA antagonist, MK-801, suppresses long-term potentiation, kindling, and kindling-induced potentiation in the perforant path of the unanesthetized rat. Brain Res. 1990 Jun 11;519(1-2):89–96. doi: 10.1016/0006-8993(90)90064-i. [DOI] [PubMed] [Google Scholar]
- Grecksch G., Matthies H. Two sensitive periods for the amnesic effect of anisomycin. Pharmacol Biochem Behav. 1980 May;12(5):663–665. doi: 10.1016/0091-3057(80)90145-8. [DOI] [PubMed] [Google Scholar]
- Huang Y. Y., Kandel E. R. Recruitment of long-lasting and protein kinase A-dependent long-term potentiation in the CA1 region of hippocampus requires repeated tetanization. Learn Mem. 1994 May-Jun;1(1):74–82. [PubMed] [Google Scholar]
- Jeffery K. J., Abraham W. C., Dragunow M., Mason S. E. Induction of Fos-like immunoreactivity and the maintenance of long-term potentiation in the dentate gyrus of unanesthetized rats. Brain Res Mol Brain Res. 1990 Oct;8(4):267–274. doi: 10.1016/0169-328x(90)90039-g. [DOI] [PubMed] [Google Scholar]
- Krug M., Lössner B., Ott T. Anisomycin blocks the late phase of long-term potentiation in the dentate gyrus of freely moving rats. Brain Res Bull. 1984 Jul;13(1):39–42. doi: 10.1016/0361-9230(84)90005-4. [DOI] [PubMed] [Google Scholar]
- Link W., Konietzko U., Kauselmann G., Krug M., Schwanke B., Frey U., Kuhl D. Somatodendritic expression of an immediate early gene is regulated by synaptic activity. Proc Natl Acad Sci U S A. 1995 Jun 6;92(12):5734–5738. doi: 10.1073/pnas.92.12.5734. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matthies H., Frey U., Reymann K., Krug M., Jork R., Schroeder H. Different mechanisms and multiple stages of LTP. Adv Exp Med Biol. 1990;268:359–368. doi: 10.1007/978-1-4684-5769-8_39. [DOI] [PubMed] [Google Scholar]
- Montarolo P. G., Goelet P., Castellucci V. F., Morgan J., Kandel E. R., Schacher S. A critical period for macromolecular synthesis in long-term heterosynaptic facilitation in Aplysia. Science. 1986 Dec 5;234(4781):1249–1254. doi: 10.1126/science.3775383. [DOI] [PubMed] [Google Scholar]
- Nguyen P. V., Abel T., Kandel E. R. Requirement of a critical period of transcription for induction of a late phase of LTP. Science. 1994 Aug 19;265(5175):1104–1107. doi: 10.1126/science.8066450. [DOI] [PubMed] [Google Scholar]
- Otani S., Marshall C. J., Tate W. P., Goddard G. V., Abraham W. C. Maintenance of long-term potentiation in rat dentate gyrus requires protein synthesis but not messenger RNA synthesis immediately post-tetanization. Neuroscience. 1989;28(3):519–526. doi: 10.1016/0306-4522(89)90001-8. [DOI] [PubMed] [Google Scholar]
- Qian Z., Gilbert M. E., Colicos M. A., Kandel E. R., Kuhl D. Tissue-plasminogen activator is induced as an immediate-early gene during seizure, kindling and long-term potentiation. Nature. 1993 Feb 4;361(6411):453–457. doi: 10.1038/361453a0. [DOI] [PubMed] [Google Scholar]
- Steward O., Wallace C. S. mRNA distribution within dendrites: relationship to afferent innervation. J Neurobiol. 1995 Mar;26(3):447–449. doi: 10.1002/neu.480260316. [DOI] [PubMed] [Google Scholar]
- Wetzel W., Ott T., Matthies H. Is actinomycin D suitable for the investigation of memory processes? Pharmacol Biochem Behav. 1976 May;4(5):515–519. doi: 10.1016/0091-3057(76)90190-8. [DOI] [PubMed] [Google Scholar]
- Worley P. F., Bhat R. V., Baraban J. M., Erickson C. A., McNaughton B. L., Barnes C. A. Thresholds for synaptic activation of transcription factors in hippocampus: correlation with long-term enhancement. J Neurosci. 1993 Nov;13(11):4776–4786. doi: 10.1523/JNEUROSCI.13-11-04776.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
