Ventral nerve cord in <i>L. satsuma</i>.

<p><b>A–C:</b> Double stain against SYNORF1 (green) and anti-serotonin (magenta) immunoreactivities from the posterior end of the vestimental region to the anterior end of the trunk shows localizations of neuropil and serotonergic neurons of the ventral nerve cord. <b>D–F:</b> Double stain with anti-acetylated tubulin (green) and DAPI (blue) of the anterior part of the ventral nerve cord in the trunk shows the metameric organization of the nerve cord. The anterior is shown on the left. Yellow arrowheads indicate commissures. <b>G:</b> Ventral view of whole-mount image of <i>elav</i> expression showing the repeated pattern of neurons (arrowheads). The anterior is on the left. <b>H–J:</b> Sectioned images of <i>syt</i> (H, I) and <i>elav</i> (J) expressions. Neurons are located on the lateral side of the ventral nerve cord. Asterisks indicate the position of giant axon. <b>K−N:</b> Sections of the ventral nerve cord at positions of ganglia (K, L) and of inter ganglia (M, N) <b>O–Q:</b> Anti-acetylated tubulin (green) and anti-serotonin (magenta) immunoreactivities in a cross section of the ventral nerve cord show ventrally located serotonergic neurons and dorsally located axons. <b>R–T:</b> Double stain against SYNORF1 (green) and anti-serotonin (magenta) immunoreactivities in the opisthosome shows that the localization of serotonergic neurons in the ventral nervous system of the opisthosome. <b>U:</b> Cross section of the opisthosome shows <i>syt</i> expression in the ventral nerve cord. Scale bars: A–H, O–T = 100 µm; I−N, Q = 50 µm.