Diazoxide (Synonyms: NSC 64198, NSC 76130, SRG 95213)

Cell experiment:

Diazoxide is dissolved in DMSO to prepare 50 mM stock solution. NSC-34 cells are allowed to differentiate for 8 weeks under reduced serum conditions and then seeded in 24-well plates. Glutamate is dissolved in culture medium and added to cultures at concentration of 10 μM for 24 h. Cell treatment with 100 µM diazoxide starts 2 h before glutamate exposure. Cell viability is measured by the MTT assay[2].

Animal experiment:

Rats: Adult male Sprague-Dawley rats with induced cerebral ischemia (n=10 per group) receive an intraperitoneal injection of 0.1% DMSO (1 mL; vehicle group), diazoxide (10 mg/kg; DZ group), or diazoxide (10 mg/kg) plus 5-hydroxydecanoate (5 mg/kg; DZ + 5-HD group) 30 min after CPR. The control group (sham group, n=5) undergoes sham operation, without cardiac arrest. Mitochondrial respiratory control rate (RCR) is determined. Brain cell apoptosis is assessed using TUNEL staining. Expression of Bcl-2, Bax, and protein kinase C epsilon (PKCε) in the cerebral cortex is determined by Western blotting and immunohistochemistry[3]. Mouse: Diazoxide is prepared by diluting a 100 mM stock solution in 10% polyethoxylated castor oil in PBS. In C57BL/6 wild-type and Kir6.2(−/−) mice, a 5 μL drop of 5 mM diazoxide is topically administered to one eye of each mouse while the fellow control eye received vehicle (DMSO and 10% polyethoxylated castor oil in the same proportion as the treated eye). IOP is measured daily at 1 hour, 4 hours, and 23 hours following treatment. Treatment with diazoxide and vehicle is continued daily for 14 consecutive days[4].

References:

[1]. Coetzee WA, et al. Multiplicity of effectors of the cardioprotective agent, diazoxide. Pharmacol Ther. 2013 Nov;140(2):167-75.
[2]. Virgili N, et al. K(ATP) channel opener diazoxide prevents neurodegeneration: a new mechanism of action viaantioxidative pathway activation. PLoS One. 2013 Sep 11;8(9):e75189.
[3]. Wu H, et al. Diazoxide Attenuates Postresuscitation Brain Injury in a Rat Model of Asphyxial Cardiac Arrest by Opening Mitochondrial ATP-Sensitive Potassium Channels. Biomed Res Int. 2016;2016:1253842.
[4]. Chowdhury UR, et al. ATP-sensitive potassium (K(ATP)) channel openers diazoxide and nicorandil lower intraocular pressure in vivo. Invest Ophthalmol Vis Sci. 2013 Jul 22;54(7):4892-9.