Figure 5
Layered distribution of the GABA-IS area and the tropomyosin (TM)-IS muscle of PP of 5-day post metamorphosis juvenile. (A) Oral side view of the juvenile. (B1–B3) Higher magnification image of a PP indicated by a box (b) in (A). (B1) GABA-IS outermost layer on the luminal epithelium with a weak IS gap in between (arrow). (B2) An immuno-negative dark layer (arrow) surrounds the TM-IS layer on the outer surface of the luminal epithelium. (B3) Merged image between (B1) and (B2) positions the central luminal epithelium, TM-IS layer, and the outermost GABA-IS layer (arrow). (C) Three-D image of a PP by Amira. Arrows; GABAAR-IS projections. White arrowheads; circumoral TM-IS muscle ring. Red arrowhead; TM-IS peripheral area of the distal disc (disc). (D) Three-D reconstructed optical cross-section of a PP by Amira at the gaiter region indicated by a dotted line (d) in (C) shows the concentric distribution of TM-IS muscle layer and the GABAAR-IS layer on the luminal epithelium (asterisk). (E) Concentric distribution of GABAAR layer and GABA-IS layer on the luminal epithelium (asterisk) via an immuno-negative space (arrow) shown by a stacked confocal laser scanning micrograph of an optical cross-section of a PP. Two IS areas are partially overlapped (yellow arrow). (F) Schematic summary of a PP cross-section shows the concentric distribution of the GAD/GABA-IS layer (light brown), GABAAR-IS layer (red) and TM-IS muscle layer (orange). Dark-blue; luminal epithelium. Gray; lumen of PP. Light blue; the outer most epithelium of PP. Scale bars = 100 μm (A), 30 μm (B1), 25 μm (C,E).
