Figure 8
Serotonin immunoreactivity in the brain of Godzilliognomus frondosus. (A-F’) Maximum projections of horizontal vibratome sections (100 μm) triple labeled for serotonin immunoreactivity (5HT-IR; green), synapsin immunoreactivity (SYN-IR; magenta) and nuclear marker (NUC; blue). (A, D) Overview of the protocerebrum (A) and deutocerebum (D) of G. frondosus showing the positions of 5HT-ir cell groups sA1, sA2, sB1, sB2, sD1, sD2, sE1, sE2. In the protocerebrum, sB2 (B) and sA1 (C) show the same projection patterns as in Speleonectes tulumensis (arrows; compare to Figure 5). A conspicuous unpaired midline domain is situated in the center of the protocerebrum in the same position as in S. tulumensis (sd 2; C). (E) In the deutocerebral paired lateral antenna 1 neuropil 2 (LAN2) strong 5HT-IR can be detected and are interconnected by a 5HT-ir commissure (arrows) originating from a single 5HT-ir neuron (sE1) (arrowheads in F’). (F, F’) Additionally, neurites from eight 5HT-ir neurons (sD2) grow out anteriorly into the core of the olfactory neuropils (ONs), where they ramify to a dense meshwork as in S. tulumensis (arrows; compare to Figure 5). Abbreviations: GLO: olfactory glomerulus; HE: hemiellipsoid body; LAN2: lateral antenna 1 neuropil 2; MAN: medial antenna 1 neuropil; ON: olfactory neuropil; sA1, sA2, sB1, sB2, sD1, sD2, sE1, sE2: 5HT-ir cell groups; sd1-9, sd11-15: 5HT-ir domains.