Renal morphology of the euryhaline flounder (Platichthys flesus): distribution of arginine vasotocin receptor.

The current study characterized tubular segmentation of the European flounder nephron and localized the vasotocin receptor expression by immunohistochemistry. Flounder nephron was shown to comprise a prominent renal corpuscle, short neck segment, proximal tubule I, proximal tubule II, collecting tubule, and collecting duct. Using specific antibodies raised against flounder vasotocin receptor, specific V(1) receptor staining was detected within the glomeruli, the endothelial surface of the afferent and efferent arterioles, and the capillaries surrounding the collecting duct system. Immunostaining for the receptor was exclusively vascular and there did not appear to be a tubular component.