• The objective of this study was to investigate the contribution of small or intermediate conductance calcium-activated potassium channels (SKca & IKca) in modulating vascular function of MA in this model. (pacific.edu)
  • The remaining EDV to ACh which is referred to as the L-NAME/Indo-insensitive component, or EDHF-type relaxation was subsequently blocked by inhibiting intermediate (but not small) conductance calcium-activated potassium channels in MA of diabetic model. (pacific.edu)
  • The blocker of ATP-modulated potassium channels (K(ATP)), glibenclamide (10 microM), and of small conductance calcium-activated potassium channels (SK(Ca)), apamin (30 nM), each failed to affect ODQ-sensitive or -resistant relaxations to DEA NONOate (n=3). (ox.ac.uk)
  • Small-conductance calcium-activated potassium (KCa2) channels happen to be implicated in synaptic plasticity, cognition, and addiction, and modulating these channels can enrich the extinction understanding of food-seeking and dread behaviors. (adenosine-kinase.com)
  • Discovery of Novel Activators of Large-Conductance Calcium-Activated Potassium Channels for the Treatment of Cerebellar Ataxia. (harvard.edu)
  • Case Report on: Very Early Afterdepolarizations in HiPSC-Cardiomyocytes-An Artifact by Big Conductance Calcium Activated Potassium Current (Ibk,Ca). Cells. (harvard.edu)
  • Apamin-sensitive calcium-activated potassium currents in rabbit ventricles with chronic myocardial infarction. (harvard.edu)
  • The small conductance (SK) channels inhibitor, apamin, that selectively blocks I(A)(HP), reduced the AHP in neurons from trained, naïve, and pseudotrained rats to a similar extent, thus maintaining the difference in AHP amplitude between neurons from trained rats and controls. (nih.gov)
  • In control animals, however, incubation of MA with apamin (a SKca inhibitor) led to a further reduction of EDV. (pacific.edu)
  • nitro-L-arginine methyl ester, a nitric oxide (NO) synthase inhibitor], NPPB[5-nitro-2-(3-phenylpropylamino) benzoic acid, an ANO1 (anoctamin 1) channel inhibitor] and apamin [a small conductance Ca2+-activated K+ channel 3 (SK3) channel inhibitor].elution, the effects of Res on spontaneous contraction of colonic smooth muscle strips before and after pretreatment were recorded and compared. (shsmu.edu.cn)
  • The cytochrome P450 mono-oxygenase inhibitor ketoconazole (10 μM) had no effect in the presence of apamin. (lu.se)
  • The large-conductance Ca 2+ -activated K + channel (Maxi K + channel) inhibitor iberiotoxin significantly prevented the relaxations induced by lower concentrations (3 and 10 µmol/l) of nicorandil. (karger.com)
  • The hyperpolarization response was decreased to a similar extent by either inhibition of SK3 channel with the selective SK antagonist, apamin, or by inhibition of the BK channel with the selective antagonist, iberiotoxin (IbTX). (elsevierpure.com)
  • Apamin, a selective blocker of the SK channels responsible for part of the slow afterhyperpolarisation reduced, but did not abolish, the amplitude of the post-burst afterhyperpolarisation. (ox.ac.uk)
  • Later experiments, in which six different calmodulin-inhibitory drugs were tested on the Ca-activated K conductance of human RBCs, showed that all were potent inhibitors of this conductance and that their effect showed a correlation coefficient of 0.98 with that found on RBC Ca-ATPase, a membrane enzyme known to be activated by calmodulin ( Lackington and Orrego, 1981 ). (conicyt.cl)
  • Background: Small-conductance Ca 2+ -activated K + (SK)-channel inhibitors have antiarrhythmic effects in animal models of atrial fibrillation (AF), presenting a potential novel antiarrhythmic option. (ku.dk)
  • 2. The IK(Ca) inhibitors clotrimazole (3 μM) and 2-chlorophenyl-bisphenyl-methanol (3 μM) strongly depressed EDHF relaxations when each of them was combined with apamin (300 nM). (lu.se)
  • Thus it is probably mediated by reduction in conductance of the other calcium-dependent potassium current, sI(AHP). (nih.gov)
  • Such AHP reduction is caused by decreased conductance of one or more of the calcium-dependent potassium currents, I(AHP) and sI(AHP), that mediate the medium and slow AHPs. (nih.gov)
  • 75, 526, (1997) Johnson, S.W., Seutin, V., Bicuculline methiodide potentiates NMDA-dependent burst firing in rat dopamine neurons by blocking apamin-sensitive Ca2+-activated K+ currents. (timtec.net)
  • The rate of terminal repolarization (phase 3) is enhanced after the plateau phase due to the increasing conductance of the rapid delayed rectifier K + currents (I kr ) and the inward rectifier K + current (I k1 ). (alomone.com)
  • Notably the L-type Ca(2+) channel antagonist, nifedipine, was more effective than apamin at reducing the post-burst afterhyperpolarisation. (ox.ac.uk)
  • We suggest that Ca(2+) entry through L-type channels during an epileptiform event is selectively coupled to both apamin-sensitive and -insensitive Ca(2+) activated K(+) channels. (ox.ac.uk)
  • Furthermore, the Pi4 binds to SK channels, small conductance Ca2+-activated potassium channels. (wikipedia.org)
  • Pharmacological characterization of small-conductance Ca2+-activated K+ channels stably expressed in HEK 293 cells. (timtec.net)
  • Based on differences in unitary conductances, sensitivity to drugs, and voltage-dependence, this allowed the classification of the channels as small (SK), with unitary conductances of 4 - 14 pS that are blocked by apamin and are insensitive to voltage. (conicyt.cl)
  • Intermediate (IK) channels, on the other hand, have conductances of 11- 40 pS, are voltage-independent, may be blocked by iberiotoxin and charybdotoxin (Ch Tx), and are found in red and white blood cells, colon, lung, pancreas, and other tissues. (conicyt.cl)
  • Scorpion α-toxins (α-NaTx) inhibiting the inactivation of voltage-gated sodium channels (Nav ) are a well-studied family of small proteins. (bvsalud.org)
  • Involvement of cyclic GMP and potassium channels in relaxation evoked by the nitric oxide donor, diethylamine NONOate, in the rat small isolated mesenteric artery. (ox.ac.uk)
  • In addition, TTX, atropine, L-NAME, NPPB and apamin had no effect on the inhibitory effect of Res on spontaneous contraction of colonic smooth muscle. (shsmu.edu.cn)
  • Pi4 competes with apamin, another SK-channel toxin. (wikipedia.org)
  • Methods: Apamin-sensitive SK-channel current (I SK ) and action potentials were recorded in human right-atrial cardiomyocytes from sinus rhythm control (Ctl) patients or patients with (long-standing persistent) chronic AF (cAF). (ku.dk)
  • To enhance the genetic findings, we examined the flexibility of apamin, a KCa2 channel allosteric inhibi. (adenosine-kinase.com)
  • Finally, rapid electrical activation (5 Hz, 10 minutes) of Ctl-cardiomyocytes promoted SK2 membrane-localization, increased I SK and reduced action potential duration, effects greatly attenuated by apamin. (ku.dk)
  • Their relaxant effects on high K + -contracted preparations were smaller than those on methacholine-contracted muscle. (karger.com)
  • Western * blotting revealed the protein expression of greek small letter * alpha-subunits for both large-conductance Ca2+-activated K+ * (BKCa) channel and Na+ channel (Nav1.5) in these cells. (nih.gov)
  • By contrast, the ISK blocker apamin (100 nM) had no effect on whole-cell current, at any set [Ca2+]i (~100-450 nM). (gla.ac.uk)
  • Selective suppression of SK3 expression by dietary doxycycline (DOX) decreased SK current density in isolated myocytes, increased phasic contractions of isolated urinary bladder smooth muscle strips and exposed high affinity effects of the blocker apamin of the SK isoforms (SK1-3), suggesting an additional participation from SK2 channels. (elsevierpure.com)
  • This effect was inhibited by PACAP-(6-38), PACAP receptor antagonist, and by apamin, blocker of small-conductance Ca2+-activated K+-channels. (unipa.it)
  • In control rats, (1) I(Kv) was larger in RCSMCs than that in SCSMCs and LCSMCs, (2) I(Kv) inactivation occurred at more negative voltages in SCSMCs than those in RCSMCs and LCSMCs, (3) I(Kir) was smaller in SCSMCs than that in RCSMCs and LCSMCs, and (4) I(BKCa) did not differ between branches. (bvsalud.org)
  • In conclusion, our results suggest that PACAP controls smooth muscle contractility, acting directly on the muscle cells through PACAP-27 preferring receptors coupled to apamin-sensitive Ca2+-dependent K+-channels and indirectly through the stimulation of NO production. (unipa.it)
  • Colchicine alters apamin receptors, electrical activity, and skeletal muscle relaxation. (shengsci.com)
  • In single smooth muscle cells of the rat and rabbit portal veins, K channel openers produced an outward current sensitive to glibenclamide, 4-AP, and TEA (1 mM), but insensitive to apamin and charybdotoxin. (elsevierpure.com)
  • charybdotoxin (CTX 5 μm) + apamin (APA 10 μm) abolished CVD reversibly. (cancerrealitycheck.com)
  • Application of apamin to regions of the brain alters physiologically important processes, such as sleep patterns and learning and memory. (grantome.com)
  • While the sAHP in most neurons is apamin-sensitive, in some neurons such as hippocampal pyramidal cells, the sAHP is apamin-insensitive, shows a slower time course, and is modulated by activation of protein kinase A (PKA). (grantome.com)
  • Modern approaches of venomics have allowed for the discovery of venom constituents that have proven to be of pharmacological significance and have opened the way to optimization of therapeutic strategies through the use of active components such as melittin and apamin. (mdpi.com)
  • Subtypes of SK channels may be distinguished by different sensitivities to the bee venom peptide toxin apamin. (grantome.com)
  • Exogenous NO, given as sodium nitroprusside (SNP), induced a concentration-dependent suppression of the phasic contractions, which was unaffected by apamin but reduced by either PACAP-(6-38) or TTX. (unipa.it)
  • Probe Set ID Ref Seq Protein ID Signal Strength Name Gene Symbol Species Function Swiss-Prot ID Amino Acid Sequence 1367452_at NP_598278 16.8 small ubiquitin-related modifier 2 precursor Sumo2 Rattus norvegicus " Ubiquitin-like protein that can be covalently attached to proteins as a monomer or as a lysine-linked polymer. (nih.gov)
  • Nomega-nitro-L-arginine methyl ester (L-NAME), nitric oxide (NO) synthase inhibitor, reduced the PACAP-inhibitory response, and the joint application of apamin plus L-NAME produced additive effects. (unipa.it)
  • In human atrial myocytes, neither 1 μM ICAGEN (at [Ca2+]i ~ 100-450 nM), nor 100 nM apamin ([Ca2+]i ~ 250 nM) affected whole-cell current (5-10 cells, 3-5 patients/group). (gla.ac.uk)
  • Simulation studies * also unraveled that both decreased conductance of INa and increased * conductance of IK(Ca) utilized to mimic riluzole actions in * skeletal muscle cells could combine to decrease the amplitude * of action potentials and increase the repolarization of action * potentials. (nih.gov)
  • CCS cells cultured in Matrigel invasion wells demonstrated a tiny amount of invasion in the clear presence of fresh serum containing growth media. (plapathway.com)
  • Does the small conductance Ca2+-activated K+ current ISK flow under physiological conditions in rabbit and human atrial isolated cardiomyocytes? (gla.ac.uk)
  • Giommi, A. , Gurgel, A. R. B. , Smith, G. L. and Workman, A. J. (2023) Does the small conductance Ca2+-activated K+ current ISK flow under physiological conditions in rabbit and human atrial isolated cardiomyocytes? (gla.ac.uk)
  • Background: The small conductance Ca2+-activated K+ current (ISK) is a potential therapeutic target for treating atrial fibrillation. (gla.ac.uk)
  • Riluzole (10 uM) also effectively increased * Ca2+-activated K+ current (IK(Ca)) which could be reversed by * iberiotoxin (200 nM) and paxilline (1 uM), but not by apamin * (200 nM). (nih.gov)
  • Strikingly, the partial depletion of SRSF1 leads to expression changes in only a small proportion of disease-altered transcripts, indicating that not all RNA alterations need normalization and that the gene therapeutic approach is safe in the above preclinical models as it does not disrupt globally gene expression. (biomedcentral.com)
  • Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. (mdpi.com)
  • [ 31 ] Amiodarone is the most effective drug for the treatment of AF and has little ventricular proarrhythmic effects but is associated with significant extra-cardiovascular toxicity. (medscape.com)