Effects of adaptation to sea water, 170% sea water and to fresh water on activities and subcellular distribution of branchial Na+?K+-ATPase, low- and high affinity Ca++-ATPase, and ouabain-insensitive ATPase inGillichthys mirabilis

Doneen, Byron A.

doi:10.1007/bf00782593

Cited by 33 publications

(20 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lasserre (1971) Lasserre & Gallis (1975) and Gallis & Bourdichon (1976) reported that Chelon lubrosus showed strongly increased gill Na+-K' ATPase activity in FW, with values twice those in SW, as we observed for M. cephalus juveniles, while results for Liza rumada were discordant. Furthermore, a high Na'-K' ATPase activity in FW has been reported in several marine euryhaline species (Kirschner 1968, Towle et al 1977, Doneen 1981, Stagg & Shuttleworth 1982. A reverse pattern has been observed in other species (De Renzis & Bornancin 1984).…”

Section: Discussionmentioning

confidence: 83%

Acclimation trial ofMugil cephalus juveniles to freshwater: morphological and biochemical aspects

et al. 1995

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 83%

Acclimation trial ofMugil cephalus juveniles to freshwater: morphological and biochemical aspects

et al. 1995

View full text Add to dashboard Cite

“…[35][36][37] (6,38), although conflicting evidence exists (14). Perry (6)(7)(8)(9)(10)(11)(12), although the possibility of other active transport pathways has not been ruled out. Although the resent study does not address the mechanism(s) ofactive Ca + uptake, the methods used should prove useful in determining both the mechanism(s) and the regulation of Ca2`transport.…”

Section: Discussionmentioning

confidence: 99%

Calcium uptake in the skin of a freshwater teleost.

McCormick

Hasegawa

Hirano

1992

Proc. Natl. Acad. Sci. U.S.A.

128

View full text Add to dashboard Cite

The skin, particularly the opercular membrane of some teleosts, contains mitochondrion-rich "chloride" cells and has been widely used as a model to study branchial salt-extrusion mechanisms in seawater fish. Skin isolated from the operculum of the freshwater Nile tilapia (Oreochromis nilotcus) can transport Ca2' against an ionic and electrical gradient. Adaptation of Nile tilapia to a low-Ca21 environment increased the capacity ofthe opercular membrane to transport Ca2+. The density of mitochondrion-rich cells increased in parallel with Ca2' transport capacity. The results demonstrate net Ca2+ uptake by vertebrate skin and strongly implicate mitochondrion-rich cells as the site of Ca2+ uptake in fresh water.Calcium is necessary for a variety of functions in animals, including bone and scale growth, muscle contraction, transmission of nerve impulses, hormone secretion, and intracellular signaling. In animals living in fresh water, calcium can be obtained from food or from the surrounding medium. Freshwater fish have the capacity to maintain normal blood Ca2+ levels (2-4 mM) in a wide range of external Ca2+ concentrations (<0.01 mM), even when food is withheld for long periods (1-3). Although the gills (4-12) and skin (5, 13) have both been implicated as sites of Ca2`uptake in teleosts, net Ca2' uptake in isolated skin or gill tissue has not, to our knowledge, previously been demonstrated. The present study was undertaken to determine whether net Ca2' uptake occurs in fish skin in vitro and whether mitochondrion-rich (MR) cells are involved in Ca2+ uptake. MATERIALS AND METHODSThe Nile tilapia Oreochromis niloticus is an Old World cichlid endemic to the freshwater lakes of the Rift Valley of Africa. Juvenile Nile tilapia, weighing 40-60 g and previously reared in fresh water, were kept in 33-liter tanks maintained at 24 + 1°C with charcoal filtration and aeration. Fish were kept in either freshwater (FW: 0.77-1.04 mM Na+/0.54-0.58 mM Ca2+) or low-Ca2+ freshwater (LCFW: deionized water supplemented with NaCl, 0.50-0.97 mM Na+, and 0.003-0.011 mM Ca2+). Fish were maintained under experimental conditions for at least 2 weeks before sampling and were fed a maintenance ration of commercial trout chow (0.5% body weight per day). Water samples were taken intermittently from tanks containing fish to determine environmental [Na+] and [Ca2W]. Although LCFW solution contains normal, freshwater concentrations of Na+ and Cl-, it has low levels of other ions; we explicitly assume that the results obtained are due to decreased Ca2+; absence of other divalent ions does not cause morphological changes in teleost gills (14). Environmental and total plasma [Na+] and [Ca2+] were measured by atomic absorption spectrophotometry. Two-thirds of the tank volume in each group was replaced every other day. Food was withheld for 24 hr before sampling of individual fish. Fish were killed by cranial concussion and pithing and were bled from the caudal vessels into heparinized syringes. Plasma was isolated by centrifugation and sto...

show abstract

“…It should be noted that the "background" activities measured by for eels adapted to tap water (0.45 mM Ca 2 +) are comparable to the values obtained in the present study for ouabain insensitive activities in LCa group studied at the same Mg 2 + concentrations. Doneen (1981) observed a greater Mg 2 + ATPase activity in Gillichthys in FW than in fish adapted to 170% SW. The enzyme may play a physiological role in cellular homeostasis or in transferring Mg 2 + to the blood but if it is associated with the basolateral membrane of the CC the increase in activity may simply reflect an increase in the number of the CC in the gill.…”

Section: Effect Of Acclimation On Ouabain-insensitive Enzyme and A Tpmentioning

confidence: 90%

“…Fenwick (1979) reported that freshwater adapted eels had a higher Ca 2 + enzyme activity than seawater adapted fish. Doneen (1981) on the other hand did not observe any difference in the low affinity Ca 2 + ATPase between fresh and seawater Gillichthys. No changes were observed in the activity of the enzyme after transfer of fish from fresh to seawater (Ma 1976).…”

Section: Introductionmentioning

confidence: 92%

“…Mayer-Gostan et al (1983) considered that they had measured a high affinity enzyme because the Km was about 17 tM. Doneen (1981) showed that in fact two enzymes were present, one with an even lower Km (2.9 M). However, in these studies no chelating agents were present in the incubation mixture so that Ca 2 + concentrations were not carefully controlled.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of ambient ion concentrations on gill ATPases in fresh water eel,Anguilla anguilla

Mayer-Gostan

Naon

1992

Fish Physiol Biochem

View full text Add to dashboard Cite

Branchial activities of Na(+),K(+)-ATPase (ouabain sensitive), Mg(2+) ATPase (ouabain insensitive) and kinetic analysis of high and low affinity Ca(2+) ATPase were measured inAnguilla anguilla that had been acclimated to demineralized water (DW, Ca < 10 μM), freshwater (FW, Ca = 2 mM), and Low calcium freshwater (L-Ca, Ca = 0.9 mM). Na(+),K(+)-ATPase activity decreased while ouabain insensitive activity increased when ambient Ca(2+) decreased. Two kinetic forms of Ca(2+) ATPase could be resolved in each environmental condition. The stimulation coefficients of both sites or enzymes were not affected by ambient Ca(2+) concentrations. The maximal velocity of both the high and the low affinity Ca(2+) ATPase was increased when external Ca(2+) was decreased during acclimation. The low affinity Ca(2+) ATPase and the Mg(2+) stimulated enzyme could be a non specific enzyme accepting either Ca(2+) or Mg(2+). Results are compared with previous results in the literature and in relation to the branchial morphology and ionic exchanges in fish.

show abstract

Effects of adaptation to sea water, 170% sea water and to fresh water on activities and subcellular distribution of branchial Na+?K+-ATPase, low- and high affinity Ca++-ATPase, and ouabain-insensitive ATPase inGillichthys mirabilis

Cited by 33 publications

References 57 publications

Acclimation trial ofMugil cephalus juveniles to freshwater: morphological and biochemical aspects

Acclimation trial ofMugil cephalus juveniles to freshwater: morphological and biochemical aspects

Calcium uptake in the skin of a freshwater teleost.

Effects of ambient ion concentrations on gill ATPases in fresh water eel,Anguilla anguilla

Contact Info

Product

Resources

About