Potassium ( K + ) Channels

The K+ Channel, A New Hope For a Better Understanding The axons of our neurons are the pathway for the communication that exists in our nervous system. This communication takes the form of an electric signal, also called an action potential. The action potential occurs due to a change in voltage across the membrane of the axon. The change in voltage is achieved by a change in the concentrations of the ions, Na+, Ca+, and K+(1) . The cell starts with a large concentration of potassium ions, K+

Small Molecule Modulation of Voltage Gated Sodium Channels Vincenzo Carnevale and Michael L. Klein Institute for Computational Molecular Science, Department of Chemistry, Temple University, Philadelphia, PA 19122 Abstract Voltage gated sodium channels are fundamental players in animals physiology. By triggering the depolarization of the lipid membrane they enable generation and propagation of the action potential. The involvement of these channels in numerous pathological conditions makes them

Abstract Voltage gated sodium channels are fundamental players in animals physiology. By triggering the depolarization of the lipid membrane they enable generation and propagation of the action potential. The involvement of these channels in numerous pathological conditions makes them relevant target for pharmaceutical intervention. Therefore, modulation of sodium conductance via small molecule binding constitutes a promising strategy to treat a large variety of diseases. However, this approach entails

of potassium channel diversity in the brain. Introduction Brain is the most complex organ in the human body. Brain and spinal cord made up part of the nervous system called central nervous system (CNS). The cerebral cortex which is the largest part of human brain has more than 100 billion of neurones, and each connected by synapses that communicate to other neurons (Pelvig DP, et al., 2008). There are several types of ion channels present along the neurons, one of these is potassium channels. Potassium

threshold potential. (2) If the threshold of excitation is reached, all Na+ channels open and the membrane depolarizes. (3) At the peak action potential, K+ channels open and K+ begins to leave the cell. At the same time, Na+ channels close. (4) The membrane becomes hyperpolarized as K+ ions continue to leave the cell. The hyperpolarized membrane is in a refractory period and cannot fire. (5) The K+ channels close and the Na+/K+ transporter restores the resting potential. Action potentials are

Research & Methods Concerning Potassium Channels in the Cardiovascular System Response to Diabetes Mellitus and Hypertension ABSTRACT Research concerning the functional role of potassium ions in the cardiovascular system with respect to hypertension and diabetes mellitus has boomed in the past decade. Through a series of experiments, data has been gathered which shows the diverse response of K+ channels in the cardiovascular system when exposed to these diseases. In elevated glucose

favorable gradient moving potassium from the intracellular to the extracellular environment. Inwardly rectifying potassium-selective (Kir), channels encoded by the KCNJ gene family are constitutively active and favor the influx of potassium more readily than its efflux from the cells, thereby maintaining potassium homeostasis. Kir channels are also known as IRK or KCNJ channels. Fifteen mammalian KCNJ gene products have been described which result in seven distinct Kir channels (Hibino et al., 2010;

Batter syndrome is inherited autosomal recessive thick ascending loop disorder that is characterized by following clinical features: • metabolic alkalosis • hyperreninemia • hyperaldosteronism • hypokalemia (low level of plasma potassium ion) • hypomagnesaemia (high level of excreted magnesium level) • hypocalcaemia (excessive urinary losses of calcium ion) • excess production of prostaglandin E2 (PGE2). Bartter syndrome is divided to two types: neonatal and classic. In case of neonatal Bartter syndrome

Answer each of the following questions and the separate parts of each question as completely and directly as possible. Do not go off-track or give “fluff” answers, as that could count against you. 1. (6pts) Diagram a neuron and label its components. In what ways are neurons specialized for communication? How do these specializations distinguish neurons from other types of cells? The structure of a neuron consist of four main components dendrites, cell body also known as soma, synapse and axon

properties of ion channels in the membrane, and can affect synaptic integration, subthreshold