Structures and immunolocalization of Na⁺, K⁺‐ATPase, Na⁺/H⁺ exchanger 3 and vacuolar‐type H⁺‐ATPase in the gills of blennies (Teleostei: Blenniidae) inhabiting rocky intertidal areas

Abstract

The structure and immunolocalization of the ion transporters Na(+) ,K(+) -ATPase (NKA), Na(+) /H(+) exchanger (NHE3) and vacuolar-type H(+) -ATPase (VHA) were examined in the gills of teleosts of the family Blenniidae, which inhabit rocky shores with vertical zonation in subtropical seas. These features were compared among the following species with different ecologies: the amphibious rockskipper blenny Andamia tetradactylus, the intertidal white-finned blenny Praealticus tanegasimae and the purely marine yaeyama blenny Ecsenius yaeyamaensis. Light and electron microscopic observations indicated that thick gill filaments were arranged close to each other and alternately on two hemibranches of a gill arch in the opercular space of A. tetradactylus. Many mucous cells (MC) and mitochondrion-rich cells (MRC) were present in the interlamellar regions of the gill filament. An immunohistochemical study demonstrated that numerous NKA, NHE3 and some VHA were located predominantly on presumed MRCs of gill filaments and at the base of the lamellae. Analyses using serial (mirror image) sections of the gills indicated that only a few NKA immunoreactive cells (IRC) were colocalized with VHA on some MRCs in the filaments. In the gills of P. tanegasimae, NKA- and NHE3-IRCs were observed in the interlamellar region of the filaments and at the base of the lamellae. VHA-IRCs were located sparsely on the lamellae and filaments. In the gills of E. yaeyamaensis, the lamellae and filaments were thin and straight, respectively. MCs were located at the tip as well as found scattered in the interlamellar region of gill filaments. NKA-, NHE3- and VHA-IRCs were moderately frequently observed in the filaments and rarely on the lamellae. This study shows that the structure and distribution of ion transporters in the gills differ among the three blennid species, presumably reflecting their different ecologies.

Effect of dendritic organ ligation on striped eel catfish Plotosus lineatus osmoregulation

“…IHC results indicate that VHA was present in a subpopulation of ionocytes in the filament epithelium with a lack of consistent colocalization with NKA-IR cells. This pattern has been reported in a number of different species [ 62 , 63 , 64 ].…”

Feeding induces translocation of vacuolar proton ATPase and pendrin to the membrane of leopard shark (Triakis semifasciata) mitochondrion-rich gill cells

“…The presence of NKA and VHA in two distinct cell populations separates elasmobranchs from teleost fishes. In freshwater teleosts, simultaneous expression of NKA and VHA is thought to drive Na + uptake and NH 3 excretion during osmoregulation and nitrogen balance (Evans, 2011), and has been shown in gills from rainbow trout (Galvez et al, 2002; Lin et al, 1994; Wilson et al, 2000a), killifish (Katoh et al, 2003), mudskipper (Wilson et al, 2000b), zebrafish (Liao et al, 2009), and several species of intertidal blennies (Uchiyama et al, 2012). Marine teleost gills also have several types of NKA-rich cells and although not widely reported, NKA and VHA may co-localize in the same cell as observed in a small population of branchial MR cells from longhorn sculpin (Catches et al, 2006).…”

Repeated evolution of amphibious behavior in fish and its implications for the colonization of novel environments

“…1), many tended to exhibit the typical benthic cylindrical body shape that should facilitate terrestrial locomotion (Hsieh 2010;Gibb et al 2013) and help reduce desiccation (Horn and Riegle 1981;Sayer 2005). Critically, however, respiration for most amphibious fish continues to involve gills and to some extent occurs through the skin (Sayer 2005;Uchiyama et al 2012;Martin 2014), and the maintenance of moisture on these respiratory surfaces is needed to facilitate gaseous exchange and avoid asphyxiation. Terrestrial crustaceans have been particularly successful in evolving strategies for avoiding desiccation and maintaining effective respiration using gills (e.g., Farrelly andGreenaway 1987, 1992), but the possession of an exoskeleton has clearly been important in their establishment on land in this regard.…”