Amitriptyline inhibits voltage-sensitive sodium currents in rat gastric sensory neurons.

摘要: Recent studies indicate that peripheral mechanisms contribute to the analgesic effect of amitriptyline. We hypothesized amitriptyline inhibits voltage-dependent sodium currents in gastric sensory neurons. To label neurons, stomach was exposed male Sprague Dawley rats through a midline incision inject retrograde tracer DiI into wall. Seven days after surgery, nodose ganglia were harvested. Neurons dissociated and cultured for 4–24 hr record whole cell with patch-clamp technique. Amitriptyline reversibly inhibited voltage-sensitive an IC50 20 μM. At clinically relevant concentrations, peak current decreased by about 15%. This associated slowed recovery from inactivation, leading significantly enhanced cumulative inhibition during brief repetitive depolarizations. These findings are consistent use-dependent block channels may properties tricyclic antidepressants.