Given an abstract from a research paper, your task is to identify and label relationships between chemical compounds and genes mentioned in the abstract.

The relationship type must be one of ['DOWNREGULATOR', 'SUBSTRATE', 'INDIRECT-REGULATOR', 'PART-OF', 'MODULATOR-ACTIVATOR', 'REGULATOR', 'INHIBITOR', 'COFACTOR', 'UPREGULATOR', 'ACTIVATOR', 'ANTAGONIST', 'NOT', 'INDIRECT-DOWNREGULATOR', 'SUBSTRATE_PRODUCT-OF', 'INDIRECT-UPREGULATOR', 'AGONIST', 'PRODUCT-OF', 'MODULATOR', 'DIRECT-REGULATOR', 'UNDEFINED', 'AGONIST-INHIBITOR', 'AGONIST-ACTIVATOR', 'MODULATOR-INHIBITOR'].

Please format your output as a JSON array. Each entry in the array should express a single relation, formatted as ["<Entity_A>", "<RELATION_A_B>", "<Entity_B>"]. If no relations can be found, please output an empty JSON array [].

Abstract:

Characterisation of the 5-HT receptor binding profile of eletriptan and kinetics of [3H]eletriptan binding at human 5-HT1B and 5-HT1D receptors. The affinity of eletriptan ((R) -3- (1-methyl-2-pyrrolidinylmethyl) -5-[2- (phenylsulphonyl) ethyl]-1H-indole) for a range of 5-HT receptors was compared to values obtained for other 5-HT1B/1D receptor agonists known to be effective in the treatment of migraine. Eletriptan, like sumatriptan, zolmitriptan, naratriptan and rizatriptan had highest affinity for the human 5-HT1B, 5-HT1D and putative 5-ht1f receptor. Kinetic studies comparing the binding of [3H]eletriptan and [3H]sumatriptan to the human recombinant 5-HT1B and 5-HT1D receptors expressed in HeLa cells revealed that both radioligands bound with high specificity (> 90%) and reached equilibrium within 10-15 min. However, [3H]eletriptan had over 6-fold higher affinity than [3H]sumatriptan at the 5-HT1D receptor (K (D)): 0.92 and 6.58 nM, respectively) and over 3-fold higher affinity than [3H]sumatriptan at the 5-HT1B receptor (K (D): 3.14 and 11.07 nM, respectively). Association and dissociation rates for both radioligands could only be accurately determined at the 5-HT1D receptor and then only at 4 degrees C. At this temperature, [3H]eletriptan had a significantly (P<0.05) faster association rate (K (on) 0.249 min (-1) nM (-1)) than [3H]sumatriptan (K (on) 0.024 min (-1) nM (-1)) and a significantly (P<0.05) slower off-rate (K (off) 0.027 min (-1) compared to 0.037 min (-1) for [3H]sumatriptan). These data indicate that eletriptan is a potent ligand at the human 5-HT1B, 5-HT1D, and 5-ht1f receptors and are consistent with its potent vasoconstrictor activity and use as a drug for the acute treatment of migraine headache.
[["Eletriptan", "DIRECT-REGULATOR", "5-ht1f"], ["sumatriptan", "DIRECT-REGULATOR", "5-ht1f"], ["zolmitriptan", "DIRECT-REGULATOR", "human 5-HT1B"], ["eletriptan", "DIRECT-REGULATOR", "5-HT receptors"], ["[3H]eletriptan", "DIRECT-REGULATOR", "human 5-HT1B"], ["[3H]sumatriptan", "DIRECT-REGULATOR", "5-HT1B"], ["R) -3- (1-methyl-2-pyrrolidinylmethyl) -5-[2- (phenylsulphonyl) ethyl]-1H-indole", "DIRECT-REGULATOR", "5-HT receptors"], ["naratriptan", "DIRECT-REGULATOR", "5-ht1f"], ["rizatriptan", "DIRECT-REGULATOR", "human 5-HT1B"], ["[3H]sumatriptan", "DIRECT-REGULATOR", "5-HT1D"], ["[3H]eletriptan", "DIRECT-REGULATOR", "5-HT1D"], ["naratriptan", "DIRECT-REGULATOR", "5-HT1D"], ["[3H]eletriptan", "DIRECT-REGULATOR", "human recombinant 5-HT1B"], ["Eletriptan", "DIRECT-REGULATOR", "5-HT1D"], ["eletriptan", "DIRECT-REGULATOR", "5-HT receptor"], ["sumatriptan", "DIRECT-REGULATOR", "human 5-HT1B"], ["zolmitriptan", "DIRECT-REGULATOR", "5-HT1D"], ["zolmitriptan", "DIRECT-REGULATOR", "5-ht1f"], ["[3H]sumatriptan", "DIRECT-REGULATOR", "human recombinant 5-HT1B"], ["rizatriptan", "DIRECT-REGULATOR", "5-ht1f"], ["naratriptan", "DIRECT-REGULATOR", "human 5-HT1B"], ["rizatriptan", "DIRECT-REGULATOR", "5-HT1D"], ["sumatriptan", "DIRECT-REGULATOR", "5-HT1D"], ["[3H]eletriptan", "DIRECT-REGULATOR", "5-HT1B"], ["Eletriptan", "DIRECT-REGULATOR", "human 5-HT1B"]]