tram34  (Alomone Labs)

Journal: PLoS ONE

Article Title: Ovariectomy-Induced Reductions in Endothelial SK3 Channel Activity and Endothelium-Dependent Vasorelaxation in Murine Mesenteric Arteries

doi: 10.1371/journal.pone.0104686

Figure Lengend Snippet: Ovariectomy reduces SK3 channel current density in endothelial cells. A : Representative traces recorded using conventional whole-cell recording on endothelial cells isolated from mesenteric arteries obtained from control mouse. Cells were voltage clamped at their resting membrane potential and a 200 ms voltage ramp from of −80 to +60 mV was delivered to elicit whole cell currents before (control) and after subsequent bath application of apamin (apamin) and apamin+tram34 (tram34). B : SK3 and IK1 current densities isolated from digital subtraction of the traces shown in (A) for control endothelial cells. C : Representative whole-cell current density obtained from ovx endothelial cells. D : SK3 and IK1 current densities isolated from digital subtraction of the traces in (C) for ovx endothelial cells. E : Summarized whole-cell SK3 and IK1 current densities from control (black) and ovx (grey) endothelial cells measured at +30 mV. F : Normalized SK3/IK1 ratios for control (black) and ovx (grey) recordings showing reduced SK3 channel activity in ovx endothelial cells. Asterisk (*) indicates statistical significance from control (P

Article Snippet: Further, blocking IK1 channels alone with 1 µM tram34 had little effect on control and ovx arteries (control: 2.7±0.9; ovx: 8.0±1.8; n = 8; P > 0.05; ).

Techniques: Isolation, Mass Spectrometry, Activity Assay

Journal: PLoS ONE

Article Title: Ovariectomy-Induced Reductions in Endothelial SK3 Channel Activity and Endothelium-Dependent Vasorelaxation in Murine Mesenteric Arteries

doi: 10.1371/journal.pone.0104686

Figure Lengend Snippet: Reduced ACh-induced vasorelaxation due to decreased SK3 channel contribution in ovx vessels. A : (left panel) Representative force myograph recording showing tension (mN) plotted against time (s) using a mesenteric vessel obtained from control mouse. Addition of 3 µM PE increased tension and 1 µM ACh caused 64% vasorelaxation, normalized to the PE-induced tension. (right panel) Following bath washout, PE was added to pre-contract the vessel ∼50%, followed by the addition of 100 µM L-NAME and 1 µM ACh. L-NAME-induced 61% increase in PE-induced contraction and ACh reduced tension by 34%. B : Representative force myograph trace obtained from an ovx artery. C and D : Summarized results for (A and B) and for other selective inhibitors to block different vasorelaxation pathways to study their ( C ) change in tone and ( D ) contribution to ACh-induced relaxation for both control (black bars) and ovx (grey bars) vessels. C : Change in tone was obtained from tension increase in the presence of inhibitors normalized to the baseline tension (eg. 61% and 34% increase in the presence of L-NAME for control and ovx vessels, respectively, as shown in A and B). D : Contribution to ACh-induced relaxation was calculated from the difference in ACh relaxation before and after inhibitor treatment, normalized to the control (before) ACh relaxation. L-NAME blocks nitric oxide (NO) pathway; indomethacin blocks prostacyclin (PGI 2 ) pathway; apamin (apa) and tram34 (tram) together block the EDH pathway.

Article Snippet: Further, blocking IK1 channels alone with 1 µM tram34 had little effect on control and ovx arteries (control: 2.7±0.9; ovx: 8.0±1.8; n = 8; P > 0.05; ).

Techniques: Blocking Assay

Journal: PLoS ONE

Article Title: Ovariectomy-Induced Reductions in Endothelial SK3 Channel Activity and Endothelium-Dependent Vasorelaxation in Murine Mesenteric Arteries

doi: 10.1371/journal.pone.0104686

Figure Lengend Snippet: IK1 channel activity mediates TRPV4-induced vasorelaxation in ovx vessels. A : Summarized results from studies using 500 nM HC067047 (HC), a TRPV4 channel antagonist, on change in tone (left panel) and contribution to ACh-induced relaxation (right panel) using vessels obtained from both control (black) and ovx (grey) mice. B : Summarized results from studies using 300 nM GSK1016790, a TRPV4 channel agonist, on changes to vascular tension in the absence and presence of apamin (apa) and/or tram34 (tram). These studies were performed in the presence of L-NAME and indomethacin. Asterisk (*) denotes statistical significance (P

Article Snippet: Further, blocking IK1 channels alone with 1 µM tram34 had little effect on control and ovx arteries (control: 2.7±0.9; ovx: 8.0±1.8; n = 8; P > 0.05; ).

Techniques: Activity Assay, Mouse Assay

Journal: Frontiers in Cellular Neuroscience

Article Title: Differential Expression of Large-Conductance Ca2+-Activated K Channels in the Carotid Body between DBA/2J and A/J Strains of Mice

doi: 10.3389/fncel.2011.00019

Figure Lengend Snippet: For patch clamp experiments, undissociated CBs were used . The setup (A) and the image of the CB (B) are shown. Examples of K current records and mean I – V relationships in the DBA/2J (C) and the A/J mouse (D) are presented. Whole current traces were evoked by voltage steps from −80 to +60 mV with 10 mV increments for 100 ms. To construct a current–voltage curve, the mean current measured between 93 and 97 ms from the start of each voltage step. Mean currents were plotted versus the test pulse. Bars represent SEM. No statistical differences were seen between the strains. (E) The effect of iberiotoxin (a BK channel blocker; 200 nM) on outward current in GCs. The outward current was evoked by a test pulse from −80 to +20 mV for 100 ms. Iberiotoxin significantly and reversibly decreased outward current in GCs of the DBA/2J mice. However, K current in the A/J mice was not significantly affected by iberiotoxin. *, Significantly different from control and recovery. The amplitudes of K current (control and recovery) were significantly larger in GCs of the DBA/2J mice. Cont, control; Ibx, iberiotoxin; Rec, recovery.

Article Snippet: To examine the BK channel component, a single step protocol was applied with or without iberiotoxin (200 nM; Alomone Laboratories), a selective blocker for BK channels.

Techniques: Patch Clamp, Construct, Mouse Assay