Forskolin activation of an identified peptide-sensitive motoneurone in Aplysia

Activation of a physiological response by the adenylate cyclase activator, forskolin, has been suggested as a new criterion for testing the role of cyclic AMP. In Aplysia, motoneurone B16, which innervates muscle 15, is activated by the peptide egg-laying hormone (ELH). In high magnesium-low calcium medium, used to block synaptic activity, forskolin produced a similar response to ELH. Forskolin, at a concentration of 100 microM, consistently activated the ELH-sensitive neurone; vehicle produced no response while 30 microM forskolin usually produced lower levels of activity than 100 microM. The data are consistent with cyclic AMP mediation of the ELH response.