Organelle calcium-derived voltage oscillations in pacemaker neurons drive the motor program for food-seeking behavior in Aplysia

An atypical neuronal pacemaker mechanism, based on rhythmic intracellular calcium store release in an identified pair of interneurons (B63) and resulting oscillation of the neurons’ membrane potential, acts as an autonomous releaser for the irregular occurrences of the motor program for food-seeking behavior in Aplysia. The rhythmic variations of the membrane potential in B63 neurons were analyzed by Fast Fourier Transform (FFT) analysis in a cycle period bandwidth of 512 s to 8 s. The resulting power spectral density periodograms were used to identify oscillation periods of peak magnitude. The periodograms were computed from the FFT frequency spectrograms by converting the frequency band (in Hz) to its reciprocal, period (in secs). These analysis were performed in isolated buccal ganglia preparations bathed in artifical sea water (ASW), in ‘Low Ca+Co’ saline to block chemical synapses, or in ‘Low Ca+Co’ saline and after an intracellular injection of organelle membrane calcium channel b...