Longterm potentiation

CaM plays a key role in many cellular processes. In the CNS, it is involved in synaptic transmission and neuronal plasticity associated with short-term and longterm potentiation, and learning and memory processes. 

So if ACh is involved in memory function, what does it do Any attempt to answer that question has to follow some consideration of how memory is thought to be processed. Many neuroscientists believe that memory is achieved by changes in the strength of synaptic connections (activation) between neurons and that increases in such synaptic activity somehow reinforce the pattern of neuronal activity during the memorising of an event so that it can be more easily restored later. One form of such plasticity is longterm potentiation (LTP), which has been mostly studied in the hippocampus where, as in other areas associated with memory, there is the appropriate complex synaptic morphology. 

Bara, M., Bourtchouladze, R., Winder, D. G., Golan, H. and Kandel, E. Rolipram, a type IV-specific phosphodiesterase inhibitor, facilitates the establishment of long-lasting longterm potentiation and improves memory. Proc. Natl Acad. Sci. U.S.A. 95 15020-15025,1998. 

Grant, S. G., O Dell, T. J., Karl, K. A. et al. Impaired longterm potentiation, spatial learning, and hippocampal development in fyn mutant mice. Science 258 1903-1910, 1992. 

Stella N, Schweitzer P, Piomelli D. (1997). A second endogenous cannabinoid that modulates longterm potentiation. Nature. 388(6644) 773-78. 

In the hippocampus, enkephalins facilitate and dynorphins inhibit longterm potentiation (Simmons and Chavkin, 1996). Consistent with the role of these peptides in nociception, electroacupuncture selectively induces release of enkephalins and dynorphins in both human and experimental animals (Ulett et al., 1998). 

Xu L, Anwyl R, Rowan MJ (1998) Spatial exploration induces a persistent reversal of longterm potentiation in rat hippocampus [see comments]. Nature 394 891-894 Yehuda R, Antelman SM (1993) Criteria for rationally evaluating animal models of post-traumatic stress disorder. Biol Psychiatry 33 479-486... 

Several brain functions have been linked to specific glutamate receptor subtypes in selected brain regions. For example, glutamatergic neurons and NMDA receptors in the hippocampus are important for longterm potentiation (FTP), a crucial component in the formation of memory (Wilson and Tonegawa, 1997). Animal models with selective lesioning or strengthen-... 

Fazeli, M. S., Errington, M. L., Dolphin, A. C. and Bliss, T. V. P. (1988) Longterm potentiation in the dentate gyms of the anaesthetized rat is accompanied by an increase in protein efflux into push-pull cannula perfusates. Brain Res473, 51-59. 

Weisskopf MG, Castillo PE, Zalutsky RA et al (1994) Mediation of hippocampal mossy fiber longterm potentiation by cyclic AMP. Science 265 1878-82 WettschureckN, Offermanns S (2005) Mammalian G proteins and their cell type specific functions. Physiol Rev 85 1159-1204... 

Urban, N. N., and Barrionuevo, G. (1996). Induction of hebbian and non-hebbian mossy fiber longterm potentiation by distinct patterns of high-frequency stimulation. J. Neurosci. 16, 4293-4299. 

Ji, R. R., Kohno, T., Moore, K. A., and Woolf, C. J. (2003). Central sensitization and longterm potentiation—Do pain and memory share similar mechanism Trends Neurosci. 26, 696-705. 

Lu, Y. F., Hayashi, Y., Moriwaki, A., Tomizawa, K, and Matsui, H. (1996a). FK506, a Ca2+/calmodulin-dependent phosphatase inhibitor, inhibits the induction of longterm potentiation in the rat hippocampus. Neurosci. Lett. 205, 103-106. 

Ishizuka, S. and Hayashi, H., Spontaneous epileptiform bursts and longterm potentiation in rat CA3 hippocampal slices induced by chaotic stimulation of mossy fibers, Brain Research, Vol. 790, No. 1-2, 1998, pp. 108-114. 

Allen PB, Hvalby O, Jensen V, Errington ML, Ramsay M, Chaudhry FA, Bliss TV, Storm-Mathisen J, Morris RG, Andersen P, Greengard P (2000) Protein phosphatase-1 regulation in the induction of longterm potentiation heterogeneous molecular mechanisms. J Neurosci 20 3537-3543. 

Krucker T, Siggins GR, Halpain S (2000) Dynamic actin filaments are required for stable longterm potentiation (LTP) in area CAl of the hippocampus. Proc Natl Acad Sci USA 97 6856-6861... 

Lynch G, Larson J, Kelso S, Barrionuevo G, Schottler F (1983) Intra-cellnlar injections of EGTA block induction of hippocampal longterm potentiation. Nature 305 719-721. 

Xiong H, Boyle J, Winkelbauer M, Gorantla S, Zheng J, Ghorpade A, Persidsky Y, Carlson KA, Gendelman HE (2003b) Inhibition of longterm potentiation by interleukin-8 Implications for human immunodeficiency vims-1-associated dementia. J Neurosci Res 71 600-607. 

Omega-3 PUFAs are essential unsaturated fatty acids obtained from food sources or from supplements. Amongst nutritionally important polyunsaturated n-3 fatty acids, a-linolcnic acid (ALA), eicosapentae-noic acid (EPA), and docosahexaenoic acid (DHA) are highly concentrated in the brain and have antioxidative stress, anti-inflammatory and antiapoptotic effects. The exposure to n-3 fatty acids enhances adult hippocampal neurogenesis associated with cognitive and behavioral processes, promotes synaptic plasticity by increasing longterm potentiation, and modulates synaptic protein expression to stimulate the dendritic arborization and new spine formation [496]. 

Hawkins R, Son H, Arancio O (1998) Nitric oxide as a retrograde messenger during longterm potentiation in hippocampus. Prog Brain Res 118 155-172... 

Hopper RA, Garthwaite J (2006) Tonic and phasic nitric oxide signals in hippocampal longterm potentiation. J Neurosci 26 11513-11521... 

Larson J, Lynch G, Games D et al (1999) Alterations in synaptic transmission and longterm potentiation in hippocampal slices from young and aged PDAPP mice. Brain Res 840 23-35... 

Franklin Roosevelt saw the longterm potential and instinctively reserved nuclear-weapons policy to himself. 

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