(±)-Felodipine-d5 is intended for use as an internal standard for the quantification of (±)-felodipine by GC- or LC-MS. (±)-Felodipine is an inhibitor of L-type calcium channels.1 It induces relaxation of precontracted isolated porcine coronary artery segments (EC50 = 0.15 nM), which highly express L-type calcium channels.2 (±)-Felodipine is selective for L-type calcium channels over N-, R-, and P/Q-type channels at 10 µM, as well as the T-type Cav3.2 channel (IC50 = 6.8 µM).1,3 (±)-Felodipine preferentially inhibits L-type calcium channels in isolated rat portal vein over rat left ventricle (IC50s = 33.9 and 3,981 nM, respectively).4 It decreases mean arterial blood pressure and total peripheral resistance in a rabbit model of hypertension induced by renal artery ligation when administered intravenously at doses of 30 and 100 nmol/kg.5
1.Furukawa, T., Yamakawa, T., Midera, T., et al.Selectivities of dihydropyridine derivatives in blocking Ca2+ channel subtypes expressed in Xenopus oocytesJ. Pharmacol. Exp. Ther.291(2)464-473(1999) 2.Johnson, J.D., and Fugman, D.A.Calcium and calmodulin antagonists binding to calmodulin and relaxation of coronary segmentsJ. Pharmacol. Exp. Ther.226(2)330-334(1983) 3.Perez-Reyes, E., Van Deusen, A.L., and Vitko, I.Molecular pharmacology of human Cav3.2 T-type Ca2+ channels: Block by antihypertensives, antiarrhythmics, and their analogsJ. Pharmacol. Exp. Ther.328(2)621-627(2009) 4.Ljung, B.Vascular selectivity of felodipine: Experimental pharmacologyJ. Cardiovasc. Pharmacol.15(Suppl 4)S11-S16(1990) 5.Bolt, G.R., and Saxena, P.R.Acute systemic and regional hemodynamic effects of felodipine, a new calcium antagonist, in conscious renal hypertensive rabbitsJ. Cardiovasc. Pharmacol.6(4)707-712(1984)