High impact information on Kcnn1

• Differential distribution of three Ca(2+)-activated K(+) channel subunits, SK1, SK2, and SK3, in the adult rat central nervous system [1].
• By contrast, SK1 and SK2 mRNAs were below the threshold limit of detection [2].
• The small-conductance calcium activated potassium channel (SK channel) blocker dequalinium was ineffective [3].
• Dopamine neurons in the substantia nigra pars compacta often fire in an irregular, single spike mode in vivo, and a similar firing pattern can be observed in vitro when small conductance calcium-activated potassium channel blockers are applied to the bath [4].
• Presynaptic localization of the small conductance calcium-activated potassium channel SK3 at the neuromuscular junction [5].

Biological context of Kcnn1

• Large-conductance calcium-activated potassium (BK) channel currents contribute to action potential (AP) repolarization; small-conductance calcium-activated potassium channel currents generate an apamin-sensitive medium AHP (mAHP) after each AP; and bursts of APs generate long-lasting slow AHPs (sAHPs) attributable to apamin-insensitive currents [6].

Anatomical context of Kcnn1

• Using whole-cell patch-clamp experiments in transfected cell lines, we found that the compound blocks SK1, SK2 and SK3 currents with equal potency: its mean IC(50)s were 1.2, 0.8 and 1.8 microM, respectively [7].
• In normal adult animals, mRNAs for Na alpha I, and SK1, SK2, and SK3 channels were found in several brainstem regions including the lateral, medial, superior and inferior vestibular nuclei and the facial nuclei [8].
• Immunohistochemistry revealed a restricted distribution of SK1 and SK2 protein with highest densities in subregions of the hippocampus and neocortex [9].
• Immunohistological experiments were also performed and confirmed the presence of small conductance calcium-activated potassium channel type 3 protein in medial habenular nucleus, locus coeruleus and dorsal raphe [10].
• The sensitivity of EFS-induced relaxations to apamin (a small conductance calcium activated potassium channel blocker) disappeared between day 6-23 PI for both jejunum and ileum [11].

Associations of Kcnn1 with chemical compounds

• The BK channel blockers iberiotoxin and charybdotoxin blocked the response, as did the potassium channel blockers tetraethylammonium and 4-aminopyridine; the small-conductance calcium-activated potassium channel blocker apamin did not affect the response [12].

Analytical, diagnostic and therapeutic context of Kcnn1

• Specific sodium (Na alpha I, Na alpha III) and potassium (SK1, SK2, SK3) radioactive oligonucleotides were used to probe sections of rat vestibular and facial nuclei by in situ hybridization methods [8].
• Following unilateral inner ear lesion in rats, the medial vestibular nuclei were probed with Na alpha I, Na alpha III, SK1, SK2 and SK3 oligonucleotide probes: autoradiography indicated no difference between the two sides, at any of the times studied [8].

References