Hydralazine-d4 (hydrochloride) (Synonyms: 1-Hydrazinophthalazine-d4)

Hydralazine-d₄ is intended for use as an internal standard for the quantification of hydralazine by GC- or LC-MS. Hydralazine is an orally bioavailable vasodilator and antihypertensive agent.¹ It decreases DNA methylation in Jurkat cells at a concentration of 10 μM and inhibits extracellular and intracellular production of reactive oxygen species (ROS) in rat macrophages activated by phorbol 12-myristate 13-acetate at a concentration of 100 μM.^2,3 Hydralazine (100 μM) also decreases nitric oxide production and expression of inducible nitric oxide synthase (iNOS) in rat macrophages activated by LPS and interferon-γ (IFN-γ).³ It reduces contraction of rat aortic arterial strips induced by potassium and norepinephrine .⁴ Hydralazine (2.6 mg/kg) lowers mean arterial blood pressure (MAP) by 41.76% in conscious rats.⁵ Formulations containing hydralazine have been used in the treatment of high blood pressure and heart failure.

1.Cohn, J.N., McInnes, G.T., and Shepherd, A.M.Direct-acting vasodilatorsJ. Clin. Hypertens. (Greenwich)13(9)690-692(2011) 2.Cornacchia, E., Golbus, J., Maybaum, J., et al.Hydralazine and procainamide inhibit T cell DNA methylation and induce autoreactivityJ. Immunol.140(7)2197-2200(1988) 3.Leiro, J.M., Alvarez, E., Arranz, J.A., et al.Antioxidant activity and inhibitory effects of hydralazine on inducible NOS/COX-2 gene and protein expression in rat peritoneal macrophagesInt. Immunopharmacol.4(2)163-177(2004) 4.Orallo, F., Gil-Longo, J., BardÁn, B., et al.Comparison of the effects of hydralazine and nifedipine on contractions and 45Ca influx of rat aortaJ. Pharm. Pharmacol.43(5)356-359(1991) 5.Siddiqui, A.A., Mishra, R., Shaharyar, M., et al.Triazole incorporated pyridazinones as a new class of antihypertensive agents: Design, synthesis and in vivo screeningBioorg. Med. Chem. Lett.21(3)1023-1026(2011)