Skip to main content
Fig. 6 | BMC Biology

Fig. 6

From: Ancient role of vasopressin/oxytocin-type neuropeptides as regulators of feeding revealed in an echinoderm

Fig. 6

Comparison of asterotocin and asterotocin receptor expression in A. rubens using double-labelling fluorescence immunohistochemistry. Comparison of the distribution of asterotocin immunoreactivity (Ast-ir; green) and asterotocin receptor immunoreactivity (AstR-ir; red) in A. rubens reveals ‘salt and pepper’ patterns of labelling consistent with expression largely in different, but often adjacent, populations of cells/processes. In the few instances where labelling appears yellow/orange, this could be due to the co-localisation of asterotocin and the asterotocin receptor in processes or alternatively it may simply reflect where asterotocin-containing fibres happen to be positioned directly above asterotocin receptor containing fibres. a Radial nerve cord showing Ast-ir cells (yellow arrowheads) and AstR-ir cells (white arrowheads) in the ectoneural epithelium and Ast-ir processes (yellow arrow) and AstR processes (white arrow) in the ectoneural neuropile. b Marginal nerve; AstR-ir cells (white arrowhead) in the epithelial layer and both Ast-ir processes (yellow arrow) and AstR-ir processes (white arrow) in the underlying neuropile. c Disc region of a tube foot; Ast-ir processes (yellow arrow) and AstR-ir processes (white arrow) in the basal nerve ring. d Cardiac stomach; Ast-ir processes (white arrowhead) and AstR-ir processes (blue arrow) in the basiepithelial nerve plexus and mucosa, while in the visceral muscle layer, only AstR-ir is present (white arrow). Abbreviations: BNR, basal nerve ring; BNP, basiepithelial nerve plexus; CS, cardiac stomach; CT, collagenous tissue; Ec, ectoneural; Lu, lumen; ML, mucosal layer; TF, tube foot; VML, visceral muscle layer. Scale bars: d = 30 μm; c = 20 μm; a, b = 10 μm

Back to article page