Sökning: "leak current"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden leak current.

  1. 1. Applying the Pump and Leak Hypothesis. An experimental and theoretical investigation of the principles of ion regulation and excitability in the crustacean stretch receptor neuron

    Författare :Sten Theander; Människan i rörelse: hälsa och rehabilitering; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Neurology; neuropsychology; lobster; stretch receptor neuron; leak current; Q-current; K-Cl cotransporter; A-current; mathematical model; excitability; GABA channel; neurophysiology; ion regulation; neuropsykologi; Neurologi; neurofysiologi;

    Sammanfattning : An invertebrate nerve cell preparation, the lobster stretch receptor neuron, was investigated with respect to maintenance of its resting voltage, intracellular ion concentrations and excitability using voltage clamp technique and ion-selective microelectrodes. It was found that the resting voltage (-65 mV) of microelectrode impaled cells is caused by (a) a homogenous population of K+ channels which we denoted as leak channels (b) an electrogenic and voltage-dependent Na-K pump current and (c) an inward microelectrode-induced "impalement" current carried mainly by Na+. LÄS MER

  2. 2. Chloride Homeostasis in Central Neurons

    Författare :Tushar Yelhekar; Staffan Johansson; Michael Druzin; Merab Kokaia; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; chloride concentration; current-voltage relation; interpolation; voltage ramp; reversal potential; [Cl–]i recovery; KCC2; extracellular matrix; GABAA receptor; chloride leak conductance; neurosteroid; fysiologi; Physiology;

    Sammanfattning : The overall aim of the present thesis is to clarify the control of intracellular chloride homeostasis in central neurons, because of the critical role of chloride ions (Cl–) for neuronal function. Normal function of the central nervous system (CNS) depends on a delicate balance between neuronal excitation and inhibition. LÄS MER

  3. 3. Neuromodulation within a spinal locomotor network : Role of metabotropic glutamate receptor subtypes

    Författare :Petronella Kettunen; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; mGluR1; mGluR5; spinal cord; modulation; glutamate; NMDA; leak channel; locomotion; endocannabinoids; lamprey.;

    Sammanfattning : The metabotropic glutamate receptors, mGluRs, are G-protein coupled receptors. They consist of eight cloned subtypes, which are divided into three groups depending on the amino acid sequence similarity, pharmacology and their signal pathways. LÄS MER

  4. 4. The role of sarcoplasmic calcium in skeletal muscle training adaptation

    Författare :Niklas Ivarsson; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP;

    Sammanfattning : Current research shows a clear correlation between strong mitochondrial capacity, healthy muscle and general public health. A sedentary lifestyle increases the risk of a whole host of so called ‘western diseases’, while an active lifestyle reduce the risk of said diseases. Thus, well-functioning muscles are a necessity for general health. LÄS MER

  5. 5. K+ channels and the regulation of synaptic transmission

    Författare :Evanthia Nanou; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP;

    Sammanfattning : Neuronal excitability is highly regulated by K+ channels that are activated by a voltage change across the plasma membrane or by a rise in intracellular Na+ or Ca2+ concentration. The main focus of this thesis has been to characterize the Na+-activated K+ (KNa) and the Ca2+-activated K+ (KCa) channels and to determine their role in regulating synaptic transmission in the lamprey spinal cord. LÄS MER