Naratriptan (hydrochloride)

Naratriptan is a potent agonist of the serotonin (5-HT) receptor subtypes 5-HT_1B and 5-HT_1D (IC₅₀s = 9.4 and 1.5 nM, respectively, in a radioligand binding assay using human recombinant receptors).¹ It is selective for 5-HT_1B and 5-HT_1D, lacking activity in rat aorta, guinea pig colon, and pig vena cava, that highly express 5-HT_2A, 5-HT₄, and 5-HT₇ receptors, respectively, at concentrations up to 10 μM.² Naratriptan induces contraction of isolated human coronary arteries (EC₅₀ = 170 nM). In vivo, naratriptan (1-300 μg/kg) induces dose-dependent vasoconstriction of the carotid vascular bed in dogs. It also inhibits plasma protein extravasation induced by electrical stimulation of the trigeminal ganglion in the dura of anesthetized rats. Formulations containing naratriptan have been used in the treatment of migraine headaches.

WARNING This product is not for human or veterinary use.

1. Doménech, T., Beleta, J., and Palacios, J.M. Characterization of human serotonin 1D and 1B receptors using [³H]-GR-125743, a novel radiolabelled serotonin 5HT1D/1B receptor antagonist. Naunyn Schmiedebergs Arch. Pharmacol. 356(3), 328-334 (1997).

2. Connor, H.E., Feniuk, W., Beattie, D.T., et al. Naratriptan: Biological profile in animal models relevant to migraine. Cephalalgia 17(3), 145-152 (1997).