Lege Artis Medicinae

[ATP-sensitive potassium channels, and their modulators]

FINTA P. Ervin1, PETER Illes2

MARCH 31, 1992

Lege Artis Medicinae - 1992;2(03)

[Recently great interest has been concentrated on potassium channels inhibited by intracellular adenosine triphosphate (ATP-sensitive potassium channels), which connect the metabolic state of cells with their electrical activity. Channel closure initiates the secretion of insulin from pancreatic ß-cells; a number of hormones altering the level of blood-sugar act via these channels. The channels are present in neurones; they regulate both in the cell bodies and the nerve terminals (e. g. peripheral nerves) the excitability. The reby, in the central nervous system, they influence the neuronal activity both in the satiety center and some catecholaminergic brain nuclei. These channels mediate the effects of endogenous vasodilators in vascular smooth muscle. They have a pathophysiological role in protecting neurones and muscle cells from hypoxic damage. The ATP-sensitive potassium channels are targets of the sulphonylurea antidiabetic agents and of a new class of drugs, the potassium channel agonists. The latter compounds are investigated or used for the treatment of hypertension, angina pectoris, cardiac insufficiency, bronchial asthma, irritable bladder syndrome, chronic occlusive arterial disease and even in impotence. They are relatively well-tolerated drugs. Their adverse effects are related to their basic vasodilator profile and most commonly include headache, dizziness, palpitation or oedema. ]

AFFILIATIONS

  1. Szt. Imre Kórház, I. Belgyógyászat, Budapest
  2. Pharmakologisches Institut der Universität, Freiburg, BRD

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