China
Africa
Explore chapters and articles related to this topic
Hypobaric Hypoxia: Adaptation and Acclimatization
Published in Anthony N. Nicholson, The Neurosciences and the Practice of Aviation Medicine, 2017
John H. Coote, James S. Milledge
Such reactions are involved in learning and memory which involve the neocortex and structures in the medial temporal lobe including the hippocampus. In the hippocampus, transmission has been shown to be enhanced for a long time following a brief burst of stimuli in a process termed long-term potentiation (LTP). Long-term potentiation is thought to be a neural process underlying learning and memory, and such an event at the synapse includes activation of a type of glutamate receptor known as the N-methyl-D-aspartate (NMDA) receptor on the post-synaptic membrane. After activation by a neurotransmitter, this receptor only allows a limited amount of calcium entry into the post-synaptic cell, initially causing a small membrane depolarization that then leads to activation of a second class of glutamate receptor, the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor. As a consequence, more calcium channels open and there is a large increase in calcium-dependent post-synaptic currents, a strong depolarization of the membrane and action potential generation.
Biomedical Applications of Organic Conducting Polymers
Published in John R. Reynolds, Barry C. Thompson, Terje A. Skotheim, Conjugated Polymers, 2019
Alexander R. Harris, Paul J. Molino, Caiyun Wang, Gordon G. Wallace, Zhilian Yue
Neurotransmitters can be eluted from a conducting polymer to alter cell behaviour. Electrical stimulation of overoxidised PEDOT soaked in GABA, glutamate or aspartate could induce a neural response [122]. 2-amino-5-phosphonopentanoate (AP5) or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) have been used as dopants in PPy. These compounds act as inhibitors of NMDA and AMPA-type glutamate receptors. Reduction of PPy ejected the dopant ions and blocked neural activity [123]. An electronic ion pump has also been used to deliver glutamate in the cochlea, leading to a shift in the auditory brainstem response [124].
Computational Neuroscience and Compartmental Modeling
Published in Bahman Zohuri, Patrick J. McDaniel, Electrical Brain Stimulation for the Treatment of Neurological Disorders, 2019
Bahman Zohuri, Patrick J. McDaniel
Note that, the N-methyl-D-aspartate receptor (also known as the NMDA receptor or NMDAR), is a glutamate receptor and ion channel protein found in nerve cells. The NMDA receptor is one of three types of ionotropic glutamate receptors, the others being the AMPA and kainate receptors. It is activated when glutamate and glycine (or D-serine) bind to it, and when activated it allows positively charged ions to flow through the cell membrane.99 The NMDA receptor is very important for controlling synaptic plasticity and memory function.100
Neurophysiological and molecular approaches to understanding the mechanisms of learning and memory
Published in Journal of the Royal Society of New Zealand, 2021
Shruthi Sateesh, Wickliffe C. Abraham
LTP can be generated through several intracellular signal transduction pathways, triggered by both ionotropic and metabotropic receptor activation at the relevant synapses. The major excitatory neurotransmitter in the hippocampus is glutamate, which binds to three types of ionotropic receptors: α-amino-3-hyroxy-5-methyl-isoxazole-propionic acid receptors (AMPAR), kainate receptors, and N-methyl-D-aspartate receptors (NMDAR), as well as a range of metabotropic glutamate receptors (mGluR). AMPA receptors mediate the majority of the fast excitatory synaptic transmission, while NMDA receptors are critical for the induction of most forms of LTP and LTD, expressed as changes in the AMPA receptor-mediated transmission.