Search for dissertations about: "potassium channel"

Showing result 16 - 20 of 85 swedish dissertations containing the words potassium channel.

  2. 16. The interplay of ions in the stimulation of the pancreatic -cell

    Author : Michael Eberhardson; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; diabetes; pancreatic β-cells; cytoplasmic calcium; oscillations; glucose; tetrodotoxin; tolbutamide; veratridine; tetraethylammonium; quinine; cesium; H2DIDS; furosemide; transients; microfluorometry; fura-2; MQAE; calcium channels; potassium channels; sodium channels; chloride channels; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

    Abstract : Glucose stimulation of insulin release is mediated by depolarisation of the pancreatic β-cells with accompanying entry of Ca2+ through voltage-dependent channels. An important feature of the glucose-induced depolarisation is its rhythmicity causing oscillations of the cytoplasmic Ca2+ concentration ([Ca2+]i), which trigger pulsatile release of insulin. READ MORE

  4. 17. Aspects on the modulation of potassium channels in insulin-producing beta-cells

    Author : Zuheng Ma; Karolinska Institutet; Karolinska Institutet; []
    Keywords : islets of Langerhans; over-stimulation; diazoxide; exocytosis; proteasome; microarray; Kv1.1.;

    Abstract : This thesis attempts to further clarify mechanisms behind the negative effects of overstimulation and the beneficial effect of β-cell rest. For this purpose diazoxide - opener of K+-ATP channels, which reversibly inhibits glucose-induced insulin secretion, was used as a probe. READ MORE

  5. 18. Role of the hERG-channel in arrhythmia and teratogenicity : studies in animal models and the human embryonic heart

    Author : Christian Danielsson; Karolinska Institutet; Karolinska Institutet; []
    Keywords : ;

    Abstract : Background: Drugs that inhibit cardiac repolarization are associated with potentially life threatening side effects in the form of ventricular arrhythmias in humans. Animal studies show that this mechanism also is relevant for the embryo, and that the circulatory depression results in hypoxia with embryotoxicity in the form of malformations and death as a consequence. READ MORE

  6. 19. Teratogenicity as a consequence of drug-induced embryonic cardiac arrhythmia : Common mechanism for almokalant, sotalol, cisapride, and phenytoin via inhibition of IKr

    Author : Anna-Carin Sköld; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutical biosciences; IKr; delayed rectifying K channel; embryonic cardiac arrhythmia; teratogenicity; Farmaceutisk biovetenskap; Biopharmacy; Biofarmaci; Toxicology; toxikologi;

    Abstract : During the last years, drugs that prolong the repolarisation phase of the myocardial action potential, due to inhibition of the rapid component of the delayed-rectifying potassium channel (IKr) have been in focus. In addition to arrhythmogenic potential, selective Ikr-blockers have also been shown to be embryotoxic and teratogenic in animal studies. READ MORE

  7. 20. Studies of individual pancreatic -cells : Electrophysiological analysis of rhythmic behaviour and development of new techniques

    Author : Staffan Dryselius; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cell biology; Diabetes; pancreatic beta-cells; insulin release; signal transduction; cytoplasmic calcium; oscillations; patch clamp; ATP-regulated potassium channels; voltage-dependent calcium channels; metabolism; calcium ion; strontium ion; manganese ion; wavelets; de-noising; pattern recognition; superfusion; solution changes; microscopic labelling; Cellbiologi; Cell biology; Cellbiologi; medicinsk cellbiologi; Medical Cell Biology;

    Abstract : The insulin concentration in blood varies periodically, which is believed to prevent down-regulation of the hormone receptors. Loss of the regular insulin oscillations is considered to be an early sign of developing diabetes. READ MORE