Table 1.
Keywords used for searches related to pain modulators and their molecular targets
| Number | Topic | Keywordsa used in addition to “pain” or “pain and migraine” |
|---|---|---|
| 1 | Purinergic receptors | Purinergic receptors, adenosine receptors, A1, A2, A3, P2Y, P2X |
| 2 | Serotoninb | Serotonin |
| 3 | Bradykinin | Bradykinin |
| 4 | Substance P | Substance P, NK-1 |
| 5 | TRP channels | Transient receptor potential channels, TRPV1, TRPA1, capsaicin |
| 6 | Calcium channels | Calcium channels, T-type, N-type, CaV2.2, CaV3.2 |
| 7 | Cholecystokinin | Cholecystokinin |
| 8 | Cytokines | Cytokines, chemokine, TNF-α, IL-1β |
| 9 | GABAb | GABA, gabapentin, pregabalin |
| 10 | Glutamateb | Excitatory amino acid agonists, glutamate, AMPA, NMDA, kainate |
| 11 | Botulinum toxinsb | Botulinum toxins, Botox |
| 12 | Cannabinoids | Cannabinoids, CB1, CB2 |
| 13 | CGRPb | Calcitonin gene-related peptide, CGRP, RAMP1 |
| 14 | Neurotrophins | Nerve growth factors, BDNF, GDNF, TrkA |
| 15 | Nitric oxide synthaseb | Nitric oxide synthase, iNOS |
| 16 | Protein kinases | Protein kinases, PKA, PKC, MAPK, ERK |
| 17 | VGSC | Voltage-gated sodium channels, NAV1.3, NAV1.7, NAV1.8 |
Notes:
a
A keyword was included if its addition increased the total number of articles by ≥2%;
b
topic was searched with “migraine” added to “pain” term. As a result, the popularity index of a topic marked by “b” can be slightly lower compared with popularity of a topic not marked by “b”, despite the similar number of articles for these two topics.
Abbreviations: TRP, transient receptor potential; GABA, gamma aminobutyric acid; CGRP, calcitonin gene-related peptide; VGSC, voltage-gated sodium channels.