Table 1.
Action of cannabinoids on ionotropic cannabinoid receptorsa
| Cannabinoid | Type | Action on ICR | MCR | Currentb |
|---|---|---|---|---|
| Anandamide | Endogenous | TRPV1 [21] | CB1; CB2 | 200–500 pA |
| >0.3 μMc | >10 nM | |||
| NADA | Endogenous | TRPV1 [61] | CB1; CB2 | 300–700 pA |
| >10 nM | >100 nM | |||
| 5′,6'-EA | Endogenous | TRPV4 [62] | NAd | 20–50 pA |
| >1 μM | ||||
| ACEA | Synthetic | TRPV1 [4,23] | CB1 | 300–700 pA |
| >5 μM | >1 nM | |||
| Δ9-THC | Plant | TRPV2 [63]; TRPA1 [30] | CB1; CB2 | 100–200 pA |
| >10 μM | >10 nM | |||
| Cannabinol | Plant | TRPV2 [63]; TRPA1 [30] | NAd | 50–100 pA |
| >10 μM | ||||
| Cannabidiol | Plant | TRPV2 [63]; TRPA1 [30] | NAd | 50–100 pA |
| >10 μM | ||||
| Cannabigerol | Plant | TRPM8 [46] | NAd | NA |
| NA | ||||
| AM404 | Synthetic | TRPV1 [64,65] | AEA-trans | 200–500 pA |
| >1 μM | NA | |||
| WIN55212 | Synthetic | TRPA1 [4] | CB1; CB2 | 200–300 pA |
| >5 μM | >10 nM | |||
| AM1241 | Synthetic | TRPA1-TRPV1e | CB2 | 100–200 pA |
| >25 μM | >1 nM |
a
Abbreviations: Δ9-THC, delta(9)-tetrahydrocannabinol; 5',6'-EA, 5',6'-epoxyeicosatrienoic acid; AEA-trans, antagonist for putative anandamide transporter; ICR, ionotropic cannabinoid receptor; MCR, metabotropic cannabinoid receptor; NA, non-applicable; NADA , N-arachidonoyl-dopamine.
b
Approximate value of current magnitudes in sensory neurons.
c
Approximate threshold concentrations of cannabinoids to activate receptors.
d
Cannabinoid-like compounds do not activate CB1 and CB2.
e
Activation of TRPA1 and TRPV1 co-expressing cells.