Description
5-(N,N-hexamethylene)-Amiloride (HMA) is a derivative of amiloride with diverse biological activities. It is an allosteric antagonist of adenosine A
2A receptors (K
i = 3.3 μM). HMA inhibits the cation-selective ion channel formed by the HIV-1 viral protein Vpu when used at a concentration of 50 μM, as well as budding of virus-like particles in HeLa cells expressing the HIV-1 proteins Gag and Vpu when used at a concentration of 10 μM. It also blocks the cation-selective ion channels formed by the hepatitis C virus (HCV) protein p7. HMA (40 μM) induces necrosis in and reduces the viability of MCF-7, MDA-MB-231, T47D, SK-BR-3, Met-1, and NDL breast cancer cells but not cardiomyocytes or uterine, pulmonary, and renal epithelial cells. HMA protects against post-ischemic contractile dysfunction and reduces coronary effluent creatine phosphokinase activity in a model of ischemia-reperfusion injury using isolated rat right ventricular free walls.
Uses
5-(N,N-Hexamethylene)-amiloride (Hexamethylene amiloride) derives from an amiloride and is a potent Na+/H+ exchanger inhibitor, which decreases the intracellular pH (pHi) and induces apoptosis in leukemic cells. 5-(N,N-Hexamethylene)-amiloride (Hexamethylene amiloride) is also an inhibitor of the HIV-1 Vpu virus ion channel and inhibits mouse hepatitis virus (MHV) replication and human coronavirus 229E (HCoV229E) replication in cultured L929 cells with EC50s of 3.91 μM and 1.34 μM, respectively[1][2].
Definition
ChEBI: A member of the class of pyrazines that is amiloride in which the two amino hydrogens at position N-5 are replaced by a hexamethylene moiety, resulting in the formation of an azepane ring.
Biochem/physiol Actions
Inhibitor of Na+/H+ antiport.
in vivo
5-(N,N-Hexamethylene)-amiloride (2.5 mg/kg; i.v.; single dose) shows short half-life and lowly oral bioavailability of 4.5%[3].
In vivo pharmacokinetics in mice or rat model[3]
Dosage: 2.5 mg/kg
Administration: Intravenous injection; single does; collected 10 min and 60 min after treatment.
| t1/2 (h) | Plasma CLint (mL/min/kg) | Plasma Vss (L/kg) | Plasma AUC0-inf (h·μM) | B/P ratio | Blood CL (mL/min/kg) | Blood Vss (L/kg) |
| Female Balb/c mice | 0.62 | 86 | 2.0 | 1.5 | 1.5 | 59 | 1.4 |
| Sprague Dawley rats | 3.2 | 83.5 | 5.3 | 1.6 | 1.8 | 46.2 | 2.9 |
| % IV dose excreted in urine (0-24 h) | Renal Blood CL (mL/min/kg) | Non-Renal Blood CL (mL/min/kg) | | | | |
| Sprague Dawley rats | 0.5 | 0.2 | 46.0 | | | | |
Note: B/P means blood-to-plasma partitioning ratio; female Balb/c mice (17-27 g, non-fasted); male Sprague Dawley rats (238-325 g, overnight-fasted).
References
[1] Rich IN, et al. Apoptosis of leukemic cells accompanies reduction in intracellular pH after targeted inhibition of the Na(+)/H(+) exchanger. Blood. 2000 Feb 15;95(4):1427-34. PMID:10666221
[2] Wilson L, et al. Hexamethylene amiloride blocks E protein ion channels and inhibits coronavirus replication. Virology. 2006 Sep 30;353(2):294-306. Epub 2006 Jul 3. DOI:
10.1016/j.virol.2006.05.028[3] Buckley BJ, et al. Systematic evaluation of structure-property relationships and pharmacokinetics in 6-(hetero)aryl-substituted matched pair analogs of amiloride and 5-(N,N-hexamethylene)amiloride. Bioorg Med Chem. 2021 May 1;37:116116. DOI:
10.1016/j.bmc.2021.116116
