stromatoxin 1 sctx sensitive currents  (Alomone Labs)

Journal: PLoS ONE

Article Title: Chemokine Co-Receptor CCR5/CXCR4-Dependent Modulation of Kv2.1 Channel Confers Acute Neuroprotection to HIV-1 Glycoprotein gp120 Exposure

doi: 10.1371/journal.pone.0076698

Figure Lengend Snippet: A , Representative traces of I DR currents recorded from cultured rat hippocampal neurons under whole-cell voltage-clamp mode using the shown voltage protocol, without (control) or with gp120 treatment (10 nM, 30 min). Magnified views of current traces within the marked boxes in panel A (control – black, gp-120 – blue), as well as the corresponding test-potentials are shown in panel B . Current density plot ( C ) of neuronal I DR from recordings as shown in panel A . Data are presented as mean ± SEM, and ‘n’ numbers for each data group are mentioned within panels. In order to better visualize the changes in I DR current density at minimal depolarizing potentials, traces from -60 mV to -10 mV test-potentials are shown with magnification inside the cyan box inset. D , Blockade of currents through Kv2.1 with stromatoxin-1 (ScTx-1; 100 nM, 30 min) occluded the gp120-induced increase in I DR current density. Data are presented as mean ± SEM I DR current density at -60 mV, -50 mV and -40 mV test-potentials, deduced from the data shown in panel C . *p<0.05 indicates significantly different in comparison to control/untreated conditions at respective test-potentials; # p<0.05 indicates significantly different in comparison to gp120-treatment conditions at respective test-potentials (one way ANOVA with post-hoc Bonferroni’s correction).

Article Snippet: Recombinant mouse SDF-1α, RANTES, WZ811, Maraviroc, FK506, MK801, and SB203580 were purchased from R&D Systems – Tocris Bioscience (Minneapolis, MN); purified recombinant HIV-1 gp120 IIIB was from ImmunoDiagostics (Woburn, MA); stromatoxin-1 (ScTx-1), trypsin, and glutamate were from Sigma-Aldrich (St. Louis, MO); and Fura-2-AM, Hank’s balanced salt solution (HBSS), B27 growth supplement, Dulbecco’s modified Eagle’s medium (DMEM), GlutaMAX, penicillin/streptomycin and Neurobasal media were from Invitrogen (Life Technologies, Grand Island, NY).

Techniques: Cell Culture

Journal: The Journal of Biological Chemistry

Article Title: Selective Down-regulation of K V 2.1 Function Contributes to Enhanced Arterial Tone during Diabetes *

doi: 10.1074/jbc.M114.622811

Figure Lengend Snippet: Stromatoxin-sensitive IKv are suppressed in VSMCs from WT HFD mice. A and B, exemplar whole-cell IKv evoked by depolarizations from −85 to +65 mV and corresponding current-voltage relationships from cerebral and mesenteric (insets) LFD (n = 7 cerebral cells and 8 mesenteric cells from 5 mice) and HFD (n = 7 cerebral and 7 mesenteric cells from 5 mice) VSMCs before (i) and after (ii) psora-4 (500 nm) application and the resultant psora-4-sensitive component (iii). Average capacitance of mesenteric WT LFD and HFD cells is 18.8 ± 1.9 and 19.5 ± 1.5 pF, respectively. Average peak IKv at +65 mV in LFD and HFD mesenteric cells, respectively, were as follow: control, 37.4 ± 6.0 and 21.8 ± 3.2 pA/pF; +psora-4, 22.7 ± 3.0 and 11.9 ± 3.5 pA/pF; psora-4-sensitive, 17.2 ± 4.0 and 13.0 ± 2.4 pA/pF. C and D, representative IKv evoked by depolarization from −85 to +25 mV and the current-voltage relationship from cerebral and mesenteric (insets) LFD (n = 12 cerebral and 7 mesenteric cells from 7 mice) and HFD (n = 14 cerebral and 7 mesenteric cells from 5 mice) cells before (i) and after (ii) application of ScTx-1 (100 nm) and resultant ScTx-sensitive current (iii). Average capacitance of mesenteric WT LFD and HFD cells is 18.8 ± 1.9 and 19.5 ± 1.5 pF, respectively. Average peak IKv at +25 mV in LFD and HFD mesenteric cells, respectively, were as follows: control, 21.4 ± 3.3 and 11.5 ± 2.8 pA/pF; +ScTx, 5.0 ± 1.5 and 5.9 ± 2.0 pA/pF; ScTx-sensitive, 16.5 ± 2.5 and 5.9 ± 1.3 pA/pF. Psora-4- and ScTx-sensitive components were obtained by digital subtraction of currents in the presence of the specific inhibitor from the currents before application of the inhibitor (control). *, p < 0.05.

Article Snippet: Iberiotoxin was from Peptides International and ScTx-1 was from Alomone Labs. Data are expressed as mean ± S.E.

Techniques: