Journal: Vascular pharmacology

Article Title: GPR55 agonist lysophosphatidylinositol and lysophosphatidylcholine inhibit endothelial cell hyperpolarization via GPR-independent suppression of Na + -Ca 2+ exchanger and endoplasmic reticulum Ca 2+ refilling

doi: 10.1016/j.vph.2017.01.002

Figure Lengend Snippet: (A) Effect of 3 μM LPI on endothelial hyperpolarization to 2 μM Ach (n = 4). (B) Effect of 10 μM LPI on endothelial hyperpolarization to two consecutive administrations of 2 μM Ach (n = 3). The hyperpolarization to SKA-31 (10 μM) remained unaffected by LPI pre-exposure (n = 4). (C) Representative membrane potential recording from in situ mice aortic endothelium showing a failure of LPI (10 μM) to inhibit the hyperpolarization evoked by 10 μM SKA-31 (n = 3).

Article Snippet: Materials LPC16:0 (1-palmitoyl-2-hydroxy- sn - glycero -3-phosphocholine) was purchased from Avanti Polar Lipids, LPI from Sigma Aldrich, paxilline and SKA-31 were purchased from Alomone Labs, KB-R7943 was purchased from TCI Chemicals.

Techniques: In Situ

Journal:

Article Title: Naphtho[1,2- d ]thiazol-2-ylamine (SKA-31), a New Activator of KCa2 and KCa3.1 Potassium Channels, Potentiates the Endothelium-Derived Hyperpolarizing Factor Response and Lowers Blood Pressure S⃞

doi: 10.1124/mol.108.051425

Figure Lengend Snippet: SKA-31 and SKA-20 are potent KCa channel activators. A, chemical structures of SKA-31 and SKA-20. B, concentration-response curves for riluzole (▪), SKA-31 (▵), and SKA-20 (○) on hKCa2.1, rKCa2.2, hKCa2.3, and hKCa3.1 stably expressed in HEK-293 cells (n = 3-6 per data point). KCa2.1: riluzole: EC50, 21 ± 3 μM, nH, 2.5; SKA-20: EC50, 430 ± 100 nM; nH, 1.7; SKA-31: 2.9 ± 0.4 μM; nH 2.3; KCa2.2: riluzole: EC50, 12.8 ± 0.7 μM; nH, 2.3; SKA-20: EC50, 1.9 ± 0.3 μM; nH, 1.8; SKA-31: EC50, 1.9 ± 0.4 μM; nH, 1.7; KCa2.3: riluzole, EC50, 12.5 ± 1.2 μM; nH, 2.4; SKA-20: EC50, 1.2 ± 0.4 μM; nH, 1.9; SKA-31: 2.9 ± 0.7 μM; nH 1.7; KCa3.1: riluzole: EC50, 1.9 ± 0.3 μM; nH, 2.3; SKA-20: EC50, 115 ± 24 nM; nH, 1.6; SKA-31: EC50, 260 ± 40 nM; nH, 1.8.

Article Snippet: For intraperitoneal application, SKA-31 was dissolved at 10 mg/ml in Miglyol 812 neutral oil (caprylic/capric triglyceride; Neebee M5, Spectrum Chemicals, Gardena, CA).

Techniques: Concentration Assay, Stable Transfection

Journal:

Article Title: Naphtho[1,2- d ]thiazol-2-ylamine (SKA-31), a New Activator of KCa2 and KCa3.1 Potassium Channels, Potentiates the Endothelium-Derived Hyperpolarizing Factor Response and Lowers Blood Pressure S⃞

doi: 10.1124/mol.108.051425

Figure Lengend Snippet: A, blockade of hKCa3.1 currents activated with 2.5 μM SKA-31 by increasing concentrations of TRAM-34 or charybdotoxin. B, blockade of hKCa2.3 currents activated with 10 μM SKA-31 by increasing concentrations of apamin and NS8593. Note that the IC50 values of the pore blockers TRAM-34 (∼20 nM), charybdotoxin (∼5 nM), and apamin (∼1 nM) are unchanged, whereas the IC50 value of the negative gating modulator NS8593 is shifted roughly 10-fold to the right indicating competition. All experiments were performed with an aspartate-based pipette solution containing 250 nM free Ca2+. The external solution is aspartate Ringer.

Article Snippet: For intraperitoneal application, SKA-31 was dissolved at 10 mg/ml in Miglyol 812 neutral oil (caprylic/capric triglyceride; Neebee M5, Spectrum Chemicals, Gardena, CA).

Techniques: Transferring

Journal:

Article Title: Naphtho[1,2- d ]thiazol-2-ylamine (SKA-31), a New Activator of KCa2 and KCa3.1 Potassium Channels, Potentiates the Endothelium-Derived Hyperpolarizing Factor Response and Lowers Blood Pressure S⃞

doi: 10.1124/mol.108.051425

Figure Lengend Snippet: Pharmacokinetics of SKA-31. A, total SKA-31 plasma concentrations (mean ± S.D.) after intravenous administration of 10 mg/kg in Cremophor EL/PBS to male Sprague-Dawley rats (n = 4). The inset shows the first 24 h. The data are best-fitted as triexponential decay in keeping with a three-compartment model. B, total SKA-31 plasma concentrations after administration of 10 and 30 mg/kg i.p. in Miglyol 812 (1 μl per gram of body weight) to male Sprague-Dawley rats (n = 3). C, table showing plasma and tissue concentrations at 2 h after administration of 10 mg/kg i.p. SKA-31 to male Sprague-Dawley rats (n = 3). D, total SKA-31 plasma concentration after administration of 10 mg/kg i.p. in peanut oil (2 μl per gram of body weight) to mice (n = 5-8).

Article Snippet: For intraperitoneal application, SKA-31 was dissolved at 10 mg/ml in Miglyol 812 neutral oil (caprylic/capric triglyceride; Neebee M5, Spectrum Chemicals, Gardena, CA).

Techniques: Concentration Assay

Journal:

Article Title: Naphtho[1,2- d ]thiazol-2-ylamine (SKA-31), a New Activator of KCa2 and KCa3.1 Potassium Channels, Potentiates the Endothelium-Derived Hyperpolarizing Factor Response and Lowers Blood Pressure S⃞

doi: 10.1124/mol.108.051425

Figure Lengend Snippet: SKA-31 potentiates EDHF-type vasodilations and lowers blood pressure in mice. A, effect of increasing concentrations of SKA-31 on native KCa3.1 or KCa2.3 in mouse CAEC. KCa3.1 currents we recorded from WT mice with KCa2.3 blocked by 1 μM UCL1684; KCa2.3 currents were recorded from KCa3.1(-/-) CAEC. B, SKA-31 potentiates carotid artery dilation (EDHF-type) in response to 100 nM ACh in WT mice (KCa3.1(+/+); n = 3-7 arteries per data point) but not in KCa3.1(-/-) mice (n = 2-5 arteries per data point). C, telemetry: single injections of SKA-31 at 1, 10, and 30 mg/kg i.p. lower MAP over 24 h in normotensive WT mice (+/+) but not in KCa3.1(-/-) mice (-/-). Control, baseline MAP over 24 h before SKA-31 injection [WT (9 animals): control 99.5 ± 1.0 mm Hg (14 measurements); 1 mg/kg SKA-31 99.0 ± 2.0 mm Hg (two measurements); 10 mg/kg SKA-31 95.8 ± 1.3 mm Hg (seven measurements, P = 0.006 versus control); 30 mg/kg SKA-31 94.1 ± 1.3 mm Hg (five measurements, P = 0.0003); KCa3.1(-/-) (5 animals): control 103.7 ± 1.1 mm Hg (five measurements, P = 0.006 versus WT); 10 mg/kg SKA-31 104.3 ± 1.5 mm Hg (five measurements, P, not significant); 30 mg/kg SKA-31 102.9 ± 0.6 mm Hg (three measurements)]. After a washout period of 3 to 6 days, some animals were reused to test a second higher dose of 10 or 30 mg/kg SKA-31. D, SKA-31 (30 mg/kg i.p.) lowers MAP in angiotensin-II-induced hypertension (Ang-II) [WT (five animals): control 132 ± 3 mm Hg (n = 5); SKA-31 120 ± 4 mm Hg (n = 5, P = 0.0038)]. *, P < 0.05; **, P < 0.01.

Article Snippet: For intraperitoneal application, SKA-31 was dissolved at 10 mg/ml in Miglyol 812 neutral oil (caprylic/capric triglyceride; Neebee M5, Spectrum Chemicals, Gardena, CA).

Techniques: Injection

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Scatter plot displaying the relation between observed changes in left ventricular stroke work (SW) and mean aortic pressure (mPAO) following infusions of saline, vehicle, SKA-31 and SNP. Percent changes in mPAO, along with accompanying percent changes in SW, were first calculated in response to each infusion utilized in a given experiment. Data points from all 7 animals were then plotted against each other in a pair-wise fashion, as depicted by the individual symbols on the graph. The straight line through the symbols represents a linear regression fit to the pooled data points (r2 value = 0.82; P < 0.001).

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Representative data from one pig demonstrating the rapid and reversible effects of SKA-31 and sodium nitroprusside (SNP) following acute intravenous infusion on mean aortic pressure (mPAO) (panel A), systemic vascular conductance (panel B), measured conductance in coronary, carotid and renal arteries (panel C) and heart rate (panel D). In each panel, the sections of continuous data points displayed represent 5-min epochs that were extracted from the master data record and illustrate the basal levels and evoked changes in the measured parameters in response to the infusions. The horizontal bars and labels provided beneath each panel specify the experimental infusion for the 5-min section of data appearing immediately above each description. Note that all displayed data were acquired simultaneously during the experiment. Individual infusions were separated by a 15–20 min recovery period (indicated by the breaks between the sections of data points) and control hemodynamic data were acquired for the first 1–2 min period immediately prior to a given infusion, once a steady baseline was clearly apparent (not shown).

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Quantification of mean aortic pressure (mPAO) under control conditions and following acute infusion of SKA-31 (0.1 – 5.0 mg/ml/kg) and SNP (5.0 μg/ml/kg) (panel A). Panel B quantifies the drug-evoked changes in mPAO relative to the preceding control value for each experimental condition. N = 7 animals for both panels A and B.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Quantification of the time to maximal change in mean aortic pressure (mPAO) following intravenous infusion of either SKA-31 (0.1 – 5.0 mg/ml/kg) or SNP (5.0 μg/ml/kg). Administration of either saline or drug vehicle did not evoke measurable changes in mPAO. The response evoked by 5.0 mg/ml/kg SKA-31 was significantly faster than that elicited by SNP, as determined by two-way ANOVA; P < 0.05, n = 7 animals.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Lack of effect of SKA-31 (0.1 – 5.0 mg/ml/kg) on mean inferior vena cava pressure (mPIVC) following acute administration. Histogram displays mPIVC values recorded in response to infusions of saline, drug vehicle and the indicated dosages of SKA-31 and SNP. Values for baseline mPIVC (control) immediately preceding each infusion are designated by the black bars.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Acute administration of SKA-31 and sodium nitroprusside (SNP) reduce systemic vascular resistance (SVR). Panel A displays absolute values for SVR recorded prior to a given drug infusion and following SKA-31 and SNP infusions at the indicated dosages. For the latter data, measurements were taken during the peak change in SVR. Panel B displays the calculated percentage change in systemic vascular resistance under each infusion condition compared with the preceding control.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Quantification of evoked changes in arterial conductance calculated for the carotid, coronary and renal arteries in response to infusions of saline, drug vehicle, SKA-31 (0.1 – 5.0 mg/ml/kg) and SNP (5.0 μg/ml/kg). Histogram displays the percentage change in conductance in each artery evoked by administered drugs relative to the preceding control value for each infusion. Asterisks indicate a statistically significant difference compared with the baseline conductance value preceding a given infusion.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques:

Journal: Vascular pharmacology

Article Title: A Pharmacologic Activator of Endothelial KCa Channels Increases Systemic Conductance and Reduces Arterial Pressure in an Anesthetized Pig Model

doi: 10.1016/j.vph.2015.07.016

Figure Lengend Snippet: Quantification of the effects of acute administration of saline, drug vehicle, SKA-31 (0.1 – 5.0 mg/ml/kg) or SNP (5.0 μg/ml/kg) on left ventricular stroke volume and heart rate (panel A). No significant changes were noted for either stroke volume or heart rate in response to a given infusion compared with the values measured during the preceding control period. The histogram in panel B displays the percentage changes in left ventricular area (ALVED) and stroke work (SW), relative to the baseline values measured during the control period preceding each indicated infusion.

Article Snippet: The volume of SKA-31 distribution (Vol D ) was calculated as follows: Vol D = SKA - 31 dosage/C 0 2.5 Statistical analysis Statistical comparisons were performed using SigmaPlot (Systat Software, Inc. 2012).

Techniques: