Interactive effects of serotonin and acetylcholine on neurite elongation.
Serotonin (5-HT) inhibits elongation of neurites of specific identified neurons. Here we report a novel, growth-enabling action of another neurotransmitter, acetylcholine (ACh). When applied simultaneously with serotonin, ACh prevents the inhibition of Helisoma neuron B19 neurite elongation that would occur in response to application of 5-HT alone. We also report that ACh prevents the rise in growth cone Ca2+ that would occur in response to application of 5-HT alone and that ACh blocks the electrical excitatory effect of 5-HT on neuron B19. These results support the hypothesis that growth cone motility and neurite elongation can be regulated by voltage-gated Ca2+ fluxes and suggest that the dynamics of neurite morphology may be complexly regulated by an array of neurotransmitters, as is functional electrical activity.
McCobb
D P
DP
Department of Biology, University of Iowa, Iowa City 52242.
Cohan
C S
CS
Connor
J A
JA
Kater
S B
SB
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology*; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D005456:Fluorescent Dyes; D016257:Fura-2; D005724:Ganglia / Q000502:physiology; D007700:Kinetics; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology*; D012908:Snails; D013050:Spectrometry, Fluorescence
D001572:Benzofurans; D005456:Fluorescent Dyes; D012701:Serotonin; D000109:Acetylcholine; D002118:Calcium; D016257:Fura-2