腹足類における摂食リズムパターン発現の神経機構

抄録

Generation mechanisms of the rhythmic firing patter in the feeding motoneurons innervating the buccal muscles have been studied in several gastropods. The motoneurons are classified into three types depending on their firing phase (P, R1 or R2 phase) during a feeding cycle. It has become apparent that these firing patterns are generated by more than three types of interneurons showing their spike activity during one of the three phases and mediating their excitatory or inhibitory outputs to the motoneurons. Moreover, these interneurons show mutual interactions, suggesting that the basic firing patterns are produced by the interneuronal network. On the other hand, some electrically coupled bursting neurons have been reported in the interneuronal network, suggesting that the basic feeding rhythm is generated by these bursting neurons. Therefore, the neural network of the central pattern generator for gastropod feeding is probably composed of these interneurons and burstiag neurons.