An unusual synaptic response mediated by a serotonin neurone.
Impulse activity in an identified serotonin-containing neurone produces a delayed slow excitatory response in another identified neurone. An axon of the serotonin neurone passes very close to the follower neurone perikaryon. The synaptic response is frequently accompanied by oscillations of the membrane potential. Constant-current pulsing experiments suggest that it could result from a reduction in membrane conductance. The response is markedly voltage-sensitive, being greatly reduced at potentials in excess of about -55 mV. Serotonin, locally applied, produces a very similar effect. The response to serotonin does not involve a change in conductance to either Na+ or Cl-, but Ca2+ appears to be involved, either by virtue of its influence on K+ conductance, or directly in its transfer of charge across the membrane.
D000818:Animals; D002104:Cadmium / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D003035:Cobalt / Q000494:pharmacology; D006372:Helix, Snails / Q000502:physiology*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000502:physiology*; D012701:Serotonin / Q000502:physiology*; D013569:Synapses / Q000502:physiology*
D002104:Cadmium; D012701:Serotonin; D003035:Cobalt; D002118:Calcium