Enalapril Maleate (MK-421 Maleate), an angiotensin-converting enzyme (ACE) inhibitor, is utilized in the treatment of hypertension, chronic heart failure , and diabetic nephropathy.

Enalapril在经过酯水解作用快速转化为enalaprilat，后者是一种强效的ACE抑制剂；而Enalapril本身只是一种较弱的ACE抑制剂。Enalapril能降低外周血管阻力，但不会引起心率增加。[1]

Enalapril治疗能够消除eNOS缺乏对血压(BP)、动脉粥样硬化和肾功能障碍在nnee小鼠中的不良影响。[2] Enalapril在mdx小鼠中引起剂量依赖性的前肢力量增强。Enalapril还能剂量依赖性地减少mdx小鼠胫骨前肌中超氧阴离子的生成，这一点通过二氢乙菲啶染色观察到。Enalapril (5 mg/kg) 减少了胃肠肌肉和膈肌中肌肉坏死面积，对非肌肉区域无显著影响。[3] 阳性对照化合物Enalapril Maleate导致在链脲佐菌素(STZ)诱导的糖尿病(STZ-DM)大鼠中肾重显著增加，尿蛋白、N-乙酰-β-D-葡萄糖胺酶(NAG)和血清ET-1浓度增高，与非糖尿病大鼠相比，ET-1在肾脏中的浓度趋于增加。Enalapril Maleate还会增加糖尿病大鼠肾脏中系膜细胞增殖、基质扩张和系膜面积的扩大。将STZ-DM大鼠尿蛋白和NAG浓度降至对照值，同时对电镜下所见的变化略有改善。[4]

Single displacement binding assay: The binding assay is based on the competitive displacement of [125I]351A by Enalaprilat performed on whole endothelial cells. Subconfluent HUVECs in 6-well plates are rinsed with 2 mL binding buffer (140 mM NaCl, 2.7 mM KCl, 1.8 mM CaCl2, 1.03 mM MgCl2, 0.42 mM NaH2PO4, 10 mM HEPES, 2 mM sodium pyruvate and 5 mM glucose, pH 7.4), and the culture medium is replaced with 2.5 mL fresh binding buffer containing 5% fetal bovine serum (FBS). The Enalaprilat (2.5-12.5 μL, 0.1-50 nM) or equivalent volumes of diluent are added to the binding buffer. A saturating amount of [125I]351A (10 μL, typically 106 cpm) is then added to each sample and the plates are incubated at 37 °C for 2 hours in a thermostatic bath. The cells are then rinsed twice with 1.5 mL binding buffer. Finally, the cells are extracted with 0.5 mL NaOH 1 N, incubated for 5 minutes, and the radioactivity is counted with a gamma counter. The ratio of specific [125I]351A bound to total bound activity (B/B0) is calculated, and the inhibitory potency of Enalaprilat expressed as the concentration of ACE inhibitors able to displace 50% of the bound radioligand, i.e. the IC50.