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