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Excitatory postsynaptic potential - Wikipedia, the free encyclopedia In neuroscience, an excitatory postsynaptic potential (EPSP) is a temporary increase in postsynaptic membrane potential caused by the flow of positively charged ions into the postsynaptic cell. A postsynaptic potential is defined as excitatory if it makes it easier for the neuron to fire an action potential. The neurotransmitter most often associated with EPSPs is the amino acid glutamate, and is the main excitatory neurotransmitter in the central nervous system. en.wikipedia.org /wiki/EPSP   (431 words)

Method of simultaneously enhancing analgesic potency and attenuating dependence liability caused by exogenous and ... Alternatively, the excitatory opioid receptor antagonists of the invention can be used to pretreat patients prior to administering bimodally-acting exogenous opioids thereto, or used alone to enhance the analgesic potency and decrease the dependence liability of endogenous opioid peptides including enkephalins, dynorphins and endorphins, which are markedly unregulated in chronic pain patients. Further, the excitatory opioid receptor antagonists can be administered alone to chronic pain patients to enhance the analgesic potency and decrease the dependence liability of endogenous opioid peptides, including enkephalins, dynorphins and endorphins which normally regulate nociceptive (pain) sensitivity and which are elevated during chronic pain. This is because the excitatory opioid receptor antagonists of the invention enhance the analgesic effects of the bimodally-acting opioid agonists by attenuating the anti-analgesic excitatory side effects of said opioid agonists. xrint.com /patents/us/5512578   (7534 words)

Excitatory amino acid inhibitors for traumatic brain injury (Cochrane Review)   (Site not responding. Last check: 2007-10-24) Glutamate is the principal excitatory neurotransmitter in the brain. Trials were included if they were randomised, double-blind, controlled trials where excitatory amino acid inhibitors were administered to patients with traumatic brain injury, within 24 hours of sustaining that injury, and compared to a control group. The case for efficacy of excitatory amino acid inhibitor therapy remains unproven. www.update-software.com /abstracts/AB003986.htm   (586 words)

MIT Department of Biology: Guosong Liu   (Site not responding. Last check: 2007-10-24) This excitatory and inhibitory balance is established and maintained by a powerful “push-pull” regulatory mechanism, resulting in an optimal level of synaptic inputs in each dendritic tree. To explore the functional implications of this synaptic arrangement, we studied the functional interactions of excitatory and inhibitory inputs on dendritic trees and found that inhibitory synapses can determine the impact of adjacent excitatory synapses only if they are co-localized on the same dendritic branch and are activated coincidentally. This is the first experimental work that demonstrates the local interaction of excitatory and inhibitory synapses on the dendritic tree and supports early theoretic predictions of the properties of excitatory and inhibitory (E/I) interaction. web.mit.edu /biology/www/facultyareas/facresearch/liu.shtml   (998 words)

Autism Society of Michigan Contradictions to excitatory vestibular input: It is with extreme caution that excitatory input is imposed on a child by a therapist. Excitatory proprioceptive activities are activities that have an excitatory vestibular component (like fast bouncing on a ball to increase muscle tone) or proprioceptive activities that are done in an excitatory (stimulating) environment. Excitatory proprioceptive activities should be utilized for an under-aroused child that is not seeking child- driven excitatory vestibular input (as previously mentioned under General guideline #1). www.autism-mi.org /aboutautism/general11.html   (3411 words)

Charles F. Stevens Activation of excitatory synapses tends to cause the receiving neuron to produce nerve impulses, and activation of inhibitory synapses tends to negate the action of excitatory synapses and to prevent nerve impulses. A third advantage of the hippocampus is that, when excitatory synapses are activated with a particular temporal pattern, certain inhibitory synapses on the same cell experience the same pattern. This means that the properties of both excitatory and inhibitory synapses can be studied with the pattern of use that is typical of both (there are experimental ways of studying each type of synapse separately). www.hhmi.org /research/investigators/stevens.html   (1146 words)

Classics in the History of Psychology -- Hull (1935) An 'excitatory tendency,' as emanating from a stimulus, is a tendency for a reaction to take place more certainly and, in case it does occur, to do so more vigorously other things equal, soon after the organism has received said stimulus than at other times. The number of remote excitatory tendencies spanning a given syllable, such as ZIT, is given by the formula (n - 1) (N - n) where N is the total number of syllables in the series and n is the ordinal number of the syllable whose span value is under consideration. When learning is performed by massed practice, the ratio of the actual strength of excitatory tendency to the inhibition of delay is, on the average, constant throughout the learning process, and such as usually to leave a positive effective strength of excitatory tendency. psychclassics.yorku.ca /Hull/Conflict   (9208 words)

Reference Archive Excitatory amino acid neurotransmitters, such as L-glutamate, act at several receptors in the brain, which are sometimes referred to as N-methyl-D-aspartate (MDA) and non-NMDA receptors. Glycine inhibited excitatory responses to kainate, quisqualate and N-methyl-aspartate (NMA). Excitatory amino acids such as L-glutamate and L-aspartate are well established as neurotransmitter candidates in the mammalian central nervous system, and three types of receptor for these substances have been proposed, characterized by the agonists N-methyl-D-aspartate (NMDA), kainate and quisqualate. www.ucl.ac.uk /~smgxt01/refarch.htm   (1760 words)

Regulation of Excitatory Input to Inhibitory Interneurons of the Dentate Gyrus During Hypoxia -- Doherty and Dingledine ... a presynaptic inhibition of excitatory input to dentate interneurons Hypoxic suppression of excitatory input to dentate interneurons is attenuated by (+)- excitatory transmission in the CA3-evoked pathway from 21 ± 5% jn.physiology.org /cgi/content/full/77/1/393   (6889 words)

[Frontiers in Bioscience, d701-718, July 20, 1998] Excitatory aminoacids (aspartate and glutamate) act through two broad classes of receptors: ion channel-linked ionotropic receptors (iGluR) and metabotropic receptors (mGluR), which are coupled with G-proteins inducing intracellular messenger cascades (12). The excitatory neurotransmitter glutamate and its large receptor family is probably the most versatile and complex signaling system in the mammalian brain, and possibly also the most susceptible for pathological disturbances. Palmer A.M., Procter A.W., Stratmann G.C. and Bowen D.M.: Excitatory amino-acid-releasing and cholinergic neurons in Alzheimer´s disease. www.bioscience.org /1998/v3/d/palmada/d701-718.htm   (9354 words)

Inhibitory neurons from fetal rat cerebral cortex exert delayed axon formation and active migration in vitro -- Hayashi ... behavior of inhibitory and excitatory neurons in vitro. branching of the axons of excitatory neurons (Fig. excitatory neurons and inhibitory neurons of the fetal rat cerebral jcs.biologists.org /cgi/content/full/116/21/4419   (5618 words)

Brain - Wikipedia, the free encyclopedia EEG measures the mass changes in electrical current from the cerebral cortex, but can only detect changes over large areas of the brain with very little sub-cortical activity. Functional magnetic resonance imaging (fMRI) measures changes in blood flow in the brain, but the activity of neurons is not directly measured, nor can it be distinguished whether this activity is inhibitory or excitatory. Similarly, a positron emission tomography (PET), is able to monitor glucose metabolism in different areas within the brain which can be correlated to the level of activity in that region. en.wikipedia.org /wiki/Brain   (3661 words)

Classics in the History of Psychology -- Hull (1934a) It is clear, however, that the first or divergent mechanism, in case the several radiating excitatory tendencies within it are antagonistic (incompatible with one another in the sense that they cannot be executed by the organism simultaneously) will give rise to a competition among themselves. With this introduction to the mechanisms of divergent and convergent excitatory tendencies, we may now turn to our main concern, which is a higher synthesis obtained by combining the two into a single functional unit. The excitatory tendency to C will be weakened according to the principle of external inhibition, whereas the inhibited tendency to go into F will suffer disinhibition, the latter reanimating the excitatory tendency to go directly to F The respective tendencies which were originally as appear on p. psychclassics.yorku.ca /Hull/Hierarchy/part1.htm   (5919 words)

Trophic Factor-Induced Excitatory Synaptogenesis Involves Postsynaptic Modulation of Nicotinic Acetylcholine Receptors ... The fl bars represent the percentage of synapses with an excitatory synaptic component that developed in different concentrations of CM [25% (n = 8), 50% (n = 8), 75% (n = 9), and 100% (n = 30)]. In addition, the CM-induced excitatory synaptic component was also blocked when pairs were incubated in CM containing a receptor tyrosine kinase inhibitor (Lav A; n = 12) but not by its inactive form (Lav B; n = 5). The loss of the excitatory component of the biphasic synapse was independent of new protein synthesis. www.jneurosci.org /cgi/content/full/22/2/505   (6975 words)

Excitatory Synaptogenesis between Identified Lymnaea Neurons Requires Extrinsic Trophic Factors and Is Mediated by ... Excitatory Synaptogenesis between Identified Lymnaea Neurons Requires Extrinsic Trophic Factors and Is Mediated by Receptor Tyrosine Kinases -- Hamakawa et al. CM-induced excitatory synapse formation is blocked, however, when paired cells are incubated in CM containing either anisomycin (protein synthesis inhibitor) or actinomycin D (protein transcription inhibitor). CM-induced excitatory synapse formation was partially or completely blocked by the addition of receptor tyrosine kinase inhibitors (lavendustin A, genistein, K252a, or KT5926) but not by inactive forms of receptor tyrosine kinase inhibitors (lavendustin B and genistin). www.jneurosci.org /cgi/content/full/19/21/9306   (5184 words)

Excitatory and Inhibitory Intensity Tuning in Auditory Cortex: Evidence for Multiple Inhibitory Mechanisms -- Sutter ... The lower suppressive band's upper edge (LBUE) and upper band's lower edge (UBLE) abut the lower and upper edge of the excitatory tuning curve, respectively, whereas the lower suppressive band's lower edge (LBLE) and upper band's upper edge (UBUE) are distant from the excitatory tuning curve. In these plots, excitatory and suppressive response domains are shown rather than the inputs, as in A and B. C: the suppressive bands are distant at higher intensities, whereas in D it abuts the excitatory domain. jn.physiology.org /cgi/content/full/90/4/2629   (8269 words)

Excitatory amino acids The ionotropic excitatory amino acid receptors can be separated further into three groups based on the sequences of receptor subunits and the agonist activity of several ligands. The receptors for excitatory amino acids elevate intracellular levels of Ca and Na through NMDA, kainate and AMPA receptors. Some of the neurotoxic effects of ischemia appear to be due to the action of excitatory amino acids, probably through an elevation in the influx of calcium. www.neurosci.pharm.utoledo.edu /MBC3320/Glutamate.htm   (783 words)

What Does the Brain Know About Blood Pressure? -- Mifflin 16 (6): 266 -- Physiology to increased excitatory baroreceptor inputs by increasing the the excitatory response of NTS neurons to an increase in pressure. There is also some reduction in baroreceptor afferent input due to receptor resetting (dotted lines), although the total level of excitatory drive remains increased compared with normotension. physiologyonline.physiology.org /cgi/content/full/16/6/266   (3508 words)

Excitatory Synaptic Transmission in Neonatal Dorsal Horn: NMDA and ATP Receptors -- Bardoni 16 (2): 95 -- Physiology Excitatory Synaptic Transmission in Neonatal Dorsal Horn: NMDA and ATP Receptors -- Bardoni 16 (2): 95 -- Physiology Excitatory Synaptic Transmission in Neonatal Dorsal Horn: NMDA and ATP Receptors a primary afferent fiber or by an excitatory interneuron. physiologyonline.physiology.org /cgi/content/full/16/2/95   (2901 words)

Regulation of excitatory neural input to longitudinal intestinal muscle by myenteric interneurons -- Grider 275 (5): ... VIP/PACAP/NOS interneurons are excitatory and regulate the activity of excitatory cholinergic/tachykinin motoneurons innervating longitudinal smooth muscle. Effects of opioids on noncholinergic excitatory responses of the guinea pig isolated ileum: inhibition of release of enteric substance P. Br. Dual excitatory and inhibitory effect of nitric oxide on peristalsis in the guinea pig intestine. ajpgi.physiology.org /cgi/content/full/275/5/G973   (3690 words)

L-Glutamate and other Excitatory Amino Acids The amino acid L-Glutamate is a neurotransmitter in many central excitatory pathways. The ionotropic receptors were the first to be classified pharmacologically, largely due to the efforts of Watkins and his colleagues, and the broad scheme of NMDA receptors and non-NMDA (AMPA/kainate) ionotropic receptors, based on responses evoked by the selective agonists NMDA, AMPA and kainate is still in use. It is noteworthy that metabotropic effects of excitatory amino acid agonists have been described which do not fit into currently known scheme of receptors: it is likely that this is due to further metabotropic receptors which remain to be discovered. www.ucl.ac.uk /~smgxt01/glutamat.htm   (1267 words)

Trophic Factor-Induced Plasticity of Synaptic Connections Between Identified Lymnaea Neurons -- Woodin et al. 6 (3): ... When DM was replaced with DM, however, neither did the excitatory synapses develop nor were the inhibitory connections eliminated (3). These inappropriate inhibitory synapses are reduced in incidence by the addition of CM-derived trophic molecules (thick fl arrow), which also induce appropriate excitatory synapse formation between the paired cells. Neurotrophins induce formation of functional excitatory and inhibitory synapses between cultured hippocampal neurons. www.learnmem.org /cgi/content/full/6/3/307   (3989 words)

Selective modulation of excitatory and inhibitory microcircuits by dopamine -- Gao and Goldman-Rakic 100 (5): 2836 -- ... on excitatory transmission are target-specific and that the axon Excitatory postsynaptic potential (EPSP) amplitudes were measured between the onset and peak of EPSP from the average of 20-40 Dopamine depolarized interneuron (NP) by 1.9 mV and induced firing in the peak of EPSP in 9 of 20 traces (45%), but the average EPSP amplitude after leaving out firing was almost identical except for a prolonged time constant in P-NP synapses. www.pnas.org /cgi/content/full/100/5/2836   (4058 words)

Apparatus and method for timing the delivery of non-excitatory ETC signals to a heart - Patent 6263242 3 which is schematic functional block diagram illustrating an implantable device 21 for pacing the heart and for delivering ETC signals to the heart using the method of timing of the non excitatory signal, in accordance with a preferred embodiment of the present invention. In the cases where the device 24 is used for delivering ETC signals to the heart, the electrodes (not shown) in the implantable leads 22 are used for sensing and for delivering ETC signals and are not used for pacing the heart. However, functionally, the sensing, pacing and ETC delivery of the ETC device 64 are similar to and may be regarded as simulating the same functions of an implanted pacemaker/ETC device, such as, for example, the functions of the pacemaker/ETC device 21 of FIG. www.freepatentsonline.com /6263242.html   (14018 words)

Stanford Encyclopedia article The neural correlate of a mental representation is activated if the neurons forming the assembly operate more actively, e.g., produce higher firing rates, than in their default mode. Figure 1: Balance between inhibitory and excitatory connections among neurons. In order to achieve a stable operation of an activated neuronal assembly, there must be a subtle balance between inhibitory and excitatory connections among neurons (cf. www.hameroff.com /StanfordEncyclopediaarticle.htm   (8846 words)

Prenatal Nicotine Exposure Recruits an Excitatory Pathway to Brainstem Parasympathetic Cardioinhibitory Neurons during ...   (Site not responding. Last check: 2007-10-24) Prenatal Nicotine Exposure Recruits an Excitatory Pathway to Brainstem Parasympathetic Cardioinhibitory Neurons during Hypoxia/Hypercapnia in the Rat: Implications for Sudden Infant Death Syndrome -- HUANG et al. In animals that were exposed to nicotine in the prenatal period, hypoxia/hypercapnia recruits an excitatory pathway to CVNs during gasping. However hypoxia/hypercapnia recruited an excitatory pathway to CVNs as inspiratory gasps evoked significant increases in excitatory post-synaptic currents (EPSC) frequency during the inspiratory activity. www.pedresearch.org /cgi/content/full/58/3/562   (3512 words)

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