cAMP evokes long-term facilitation in Aplysia sensory neurons that requires new protein synthesis.
Behavioral sensitization leads to both short- and long-term enhancement of synaptic transmission between the sensory and motor neurons of the gill-withdrawal reflex in Aplysia. Serotonin (5-HT), a transmitter important for short-term sensitization, can evoke long-term enhancement of synaptic strength detected 1 day later. Because 5-HT mediates short-term facilitation through adenosine 3',5'-monophosphate (cAMP)-dependent protein phosphorylation, the role of cAMP in the long-term modulation of this identified synapse was examined. Like 5-HT, cAMP can also evoke long-term facilitation lasting 24 hours. Unlike the short-term change, the long-lasting change is blocked by anisomycin, a reversible inhibitor of protein synthesis, and therefore must involve the synthesis of gene products not required for the short-term change.
Schacher
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S
Center for Neurobiology and Behavior, Howard Hughes Medical Institute, College of Physicians and Surgeons of Columbia University, New York State Psychiatric Institute, NY 10032.
Castellucci
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VF
Kandel
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ER
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001048:Aplysia / Q000502:physiology*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000494:pharmacology*; D005071:Evoked Potentials / Q000187:drug effects; D009046:Motor Neurons / Q000502:physiology; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D014176:Protein Biosynthesis; D012701:Serotonin / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000502:physiology
C024322:8-thio-benzyl cyclic AMP; D012701:Serotonin; D000841:Anisomycin; D000242:Cyclic AMP; D015056:1-Methyl-3-isobutylxanthine