“…Serotonin (5-hydroxytriptamine: 5-HT) is contained in the central nervous system (CNS) of gastropod molluscs, particularly in the buccal and cerebral ganglia, and is involved in the control of feeding behavior (Elekes, 1992;Gietzen et al, 1992;Kemenes, 1997;Hatakeyama and Ito, 1999;Proekt and Weiss, 2003;Jacklet et al, 2006;Martínez-Rubio et al, 2009). In the pond snail Lymnaea stagnalis, a pair of serotonergic giant interneurons called the cerebral giant cells (CGCs) are found in the cerebral ganglia, and are homologous to neurons sometimes called the metacerebral cells in other gastropod molluscs; the CGCs play key roles in the feeding system of the CNS (McCrohan and Benjamin, 1980b;Kyriakides and McCrohan, 1989;Kojima et al, 1997Kojima et al, , 2001Elliott and Vehovszky, 2000;Straub et al, 2007;Yeoman et al, 2008).…”