1,2,3,4-Tetrahydro-β-carboline is a serotonin reuptake inhibitor (IC50 = 7.4 µM in rat brain homogenates) and metabolite of tryptamine .1 In vivo, 1,2,3,4-tetrahydro-β-carboline (20 and 40 µg/animal, i.c.v.) reduces serotonin levels in rat forebrain. It induces serotonin-mediated hyperactivity syndrome (HHS) in rats (ED50 = 48 mg/kg).2 1,2,3,4-Tetrahydro-β-carboline (6.25-75 mg/kg) also reduces acetic acid-induced writhing in rats.3
1.Rommelspacher, H., Bade, P., Coper, H., et al.Inhibition of the reuptake of serotonin by tryptolineNaunyn Schmiedebergs Arch. Pharmacol.292(1)93-95(1976) 2.Pannier, L., and Rommelspacher, H.Actions of tetrahydronorharmane (tetrahydro-β-carboline) on 5-hydroxytryptamine and dopamine mediated mechanismsNeuropharmacology20(1)1-8(1981) 3.Rommelspacher, H., Kauffmann, H., Cohnitz, C.H., et al.Pharmacological properties of tetrahydronorharmane (tryptoline)Naunyn Schmiedebergs Arch. Pharmacol.298(2)83-91(1977)