Hemolymph osmotic, ionic status, and branchial Na+/K+-ATPase activity under varying environmental conditions in the intertidal grapsid crab, Gaetice depressusd

No study has been done on the existence, biochemical characteristics, and modulation of K+-independent ouabain-insensitive Na+ ATPase activity (the second sodium pump) in the digestive tract of intertidal euryhaline crabs and moreover on the coexistence and modulation under distinct physiological and (or) environmental conditions of different sodium pumps. We determined the occurrence, characteristics, and responses at different times (0, 1, 24, 48, and 120 h) after feeding upon distinct salinities of Na+ ATPase activity and Na+/K+ ATPase in the hepatopancreas of Neohelice granulata (Dana, 1851), which is a model species. The stimulation by Na+ under total inhibition of Na+/K+ ATPase activity revealed the occurrence of Na+ ATPase activity that was totally inhibited by 2 mmol·L–1 furosemide, exhibits Michaelis–Menten kinetics for ATP (apparent Km = 0.52 ± 0.16 mmol·L–1), and highest activity at around pH 7.4. In crabs acclimated to 35 psu (osmoconforming conditions), Na+ ATPase activity was highly increased (about 15-fold) (532 ± 58 nmol Pi·mg protein−1·min−1) in the hepatopancreas 48 h after feeding. In 10 psu (hyper-regulating conditions), Na+ ATPase activity decreased in the hepatopancreas 24 h after feeding (7 ± 9 nmol Pi·mg protein−1·min−1) and recovered initial values after 48 h (24 ± 35 nmol Pi·mg protein−1·min−1). Unlike Na+ ATPase, Na+/K+ ATPase activity did not change after feeding at any salinity, suggesting the specific modulation of the second sodium pump and its role in postprandial adjustments in the hepatopancreas.

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The ATPase Activity of Hsp104, Effects of Environmental Conditions and Mutations

Journal of Biological Chemistry ◽

10.1074/jbc.273.25.15546 ◽

1998 ◽

Vol 273 (25) ◽

pp. 15546-15552 ◽

Cited By ~ 86

Author(s):

Eric C. Schirmer ◽

Christine Queitsch ◽

Anthony S. Kowal ◽

Dawn A. Parsell ◽

Susan Lindquist

Keyword(s):

Atpase Activity ◽

Environmental Conditions

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Localization of Adenosine Triphosphatase Activity in the Phleom of Nicotiana Tabacum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094401 ◽

1972 ◽

Vol 30 ◽

pp. 230-231

Author(s):

James Cronshaw ◽

Jamison E. Gilder

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Adenosine Triphosphatase ◽

Higher Plants ◽

High Surface ◽

Root Tip ◽

Animal Cells ◽

Physiological Processes ◽

Tip Cells ◽

Atpase Localization

Adenosine triphosphatase (ATPase) activity has been shown to be associated with numerous physiological processes in both plants and animal cells. Biochemical studies have shown that in higher plants ATPase activity is high in cell wall preparations and is associated with the plasma membrane, nuclei, mitochondria, chloroplasts and lysosomes. However, there have been only a few ATPase localization studies of higher plants at the electron microscope level. Poux (1967) demonstrated ATPase activity associated with most cellular organelles in the protoderm cells of Cucumis roots. Hall (1971) has demonstrated ATPase activity in root tip cells of Zea mays. There was high surface activity largely associated with the plasma membrane and plasmodesmata. ATPase activity was also demonstrated in mitochondria, dictyosomes, endoplasmic reticulum and plastids.

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A High Resolution Cytochemical Study of Nuclear ATPase in Human Spermatozoa

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116590 ◽

1975 ◽

Vol 33 ◽

pp. 594-595

Author(s):

A. Sosa ◽

L. Calzada

Keyword(s):

High Resolution ◽

Atpase Activity ◽

Nuclear Membrane ◽

Human Sperm ◽

Sperm Nucleus ◽

Human Spermatozoa ◽

Cytochemical Study ◽

Membrane Bound ◽

Sperm Nuclei ◽

Interchromatin Space

The dependence of nuclear metabolism on the function of the nuclear membrane is not well understood. Whether or not the function of the nuclear membrane is partial or totally responsible of the repressed template activity of human sperm nucleus has not at present been elucidated. One of the membrane-bound enzymatic activities which is concerned with the mechanisms whereby substances are thought to cross cell membranes is adenosintriphosphatase (ATPase). This prompted its characterization and distribution by high resolution photogrammetry on isolated human sperm nuclei. Isolated human spermatozoa nuclei were obtained as previously described. ATPase activity was demonstrated by the method of Wachstein and Meisel modified by Marchesi and Palade. ATPase activity was identified as dense and irregularly distributed granules confined to the internal leaflet of the nuclear membrane. Within the nucleus the appearance of the reaction product occurs as homogenous and dense precipitates in the interchromatin space.

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Ca++-ATPase activity in the hepatopancreas cells of Oniscus asellus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124501 ◽

1992 ◽

Vol 50 (1) ◽

pp. 820-821

Author(s):

G.M. Vernon ◽

A. Surace ◽

R. Witkus

Keyword(s):

B Cells ◽

Epithelial Cell ◽

Atpase Activity ◽

Calcium Transport ◽

Carcinus Maenas ◽

Cell Types ◽

Molt Cycle ◽

Copper And Zinc

The hepatopancreas consists of a pair of bilobed tubules comprised of two epithelial cell types. S cells are absorptive and accumulate metals such as copper and zinc. Ca++ concentrations vary between the S and B cells and during the molt cycle. Roer and Dillaman implicated Ca++-ATPase in calcium transport during molting in Carcinus maenas. This study was undertaken to compare the localization of Ca++-ATPase activity in the S and B cells during intermolt.

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Vibration Isolator System for Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017966x ◽

1990 ◽

Vol 48 (1) ◽

pp. 182-183

Author(s):

K. Ohi ◽

M. Mizuno ◽

T. Kasai ◽

Y. Ohkura ◽

K. Mizuno ◽

...

Keyword(s):

Electron Microscope ◽

Magnetic Fields ◽

Environmental Conditions ◽

Vibration Isolator ◽

Air Conditioners ◽

Vibration Isolators ◽

Large Size ◽

Electron Microscopes

In recent years, with electron microscopes coming into wider use, their installation environments do not necessarily give their performance full play. Their environmental conditions include air-conditioners, magnetic fields, and vibrations. We report a jointly developed entirely new vibration isolator which is effective against the vibrations transmitted from the floor.Conventionally, large-sized vibration isolators which need the digging of a pit have been used. These vibration isolators, however, are large present problems of installation and maintenance because of their large-size.Thus, we intended to make a vibration isolator which1) eliminates the need for changing the installation room2) eliminates the need of maintenance and3) are compact in size and easily installable.

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