Table 1.

Receptor antagonists tested for reversal of the inhibition of N-type calcium channel currents by α-conotoxin Vc1.1

Antagonist (concentration)Target receptorAntagonist of Vc1.1 inhibitionPercentage inhibition of IBa by Vc1.1 (n)
Mecamylamine (3 μm)nAChR29.2 ± 8.6 (3)
ACh (100 μm)nAChR28.4 ± 4.5 (7)
Atropine (1 μm)mAChR27.2 ± 10.4 (4)
Prazosin (10 μm)α1-Adrenergic41.3 ± 4.8 (3)
Yohimbine (10 μm)α2-Adrenergic35.8 ± 11.5 (3)
Naloxone (10 μm)μ-Opioid50.1 ± 12.4 (3)
Bicuculline (30 μm)GABAA32.9 ± 7.0 (10)
Phaclofen (50 μm)GABAB+4.6 ± 4.4 (9)
CGP 55845 (1 μm)GABAB+6.8 ± 4.5 (14)
CGP 54626 (1 μm)GABAB+7.4 ± 2.3 (4)
  • +, Reversal of Vc1.1 inhibition; −, no effect; mAChR, muscarinic acetylcholine receptor.