Fig. 5. Distribution of NKCC during the ontogeny of Dicentrarchus labrax. (A-F) Longitudinal section (A) and transverse sections (B-D) of 30-day-old larvae; (A) Predominant basolateral staining in branchial filamentary and opercular chloride cells (CC) (longitudinal section). (A') Larger magnification of a CC showing that the apical pit (arrow) presents no or weak immunostaining. (B,C,D,D',E,F) Apical immunostaining of the anterior (B) and posterior (C,D) intestine (I), of the collecting ducts (CD) and of the dorsal part of the urinary bladder (UB) (D,D',E,F). CT, collecting tubule; F, filament; L, lamellae; M, muscle; TI, tegumentary ionocyte. Scale bars, 5 µm (A'), 10 µm (A), 15 µm (D'), 20 µm (B,C,E,F), 50 µm (D).