Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
1. Intracellular and intercellular concentrations of sodium and potassium have been measured in pregastrular embryos of Xenopus laevis and Amblystoma mexicanum. Calcium and magnesium contents have also been determined.2. Between egg and gastrula stages of development the potassium concentration is near to 60 m-mole/l. embryo. Up to the blastula stage the sodium concentration is near to 50 m-mole/l. embryo; the amount of sodium in the embryo begins to fall just before gastrulation.3. Embryo calcium and magnesium concentrations show no significant variations prior to gastrulation. Average calcium concentrations for the different stages range from 5 to 8 m-mole/l. embryo; magnesium concentrations lie between 12.4 and 17 m-mole/l. embryo.4. The intercellular fluid contains 100 mM sodium and 1 mM potassium; the majority of the sodium is ionically active. As no net uptake of sodium or potassium occurs before gastrulation these cations must have been transferred from the cells to the cavity.5. At all developmental stages studied, the intracellular potassium concentration is close to 100 m-mole/l. cell water. Intracellular sodium falls steadily from 80 m-mole/l. cell water in eggs to 30 m-mole/l. cell water at the beginning of gastrulation.6. The intracellular sodium activity, measured with sodium sensitive intracellular micro-electrodes, is relatively constant between egg and blastula stages at about 14 mM. During each cell division cycle the intracellular sodium activity rises transiently by 2-3 mM.
ADRIAN,
The effect of internal and external potassium concentration on the membrane potential of frog muscle.
1956, Pubmed
ADRIAN,
The effect of internal and external potassium concentration on the membrane potential of frog muscle.
1956,
Pubmed
Baker,
Intracellular calcium and cell cleavage in early embryos of Xenopus laevis.
1972,
Pubmed
,
Xenbase
Baker,
Depolarization and calcium entry in squid giant axons.
1971,
Pubmed
BARTH,
Differentiation of cells of the Rana pipiens gastrula in unconditioned medium.
1959,
Pubmed
Blaustein,
The effect of cyanide on the efflux of calcium from squid axons.
1969,
Pubmed
Bosher,
Observations on the electrochemistry of the cochlear endolymph of the rat: a quantitative study of its electrical potential and ionic composition as determined by means of flame spectrophotometry.
1968,
Pubmed
Century,
The concentrations of water, sodium and potassium in the nucleus and cytoplasm of amphibian oocytes.
1970,
Pubmed
Dawid,
Deoxyribonucleic acid in amphibian eggs.
1965,
Pubmed
DESMEDT,
Electrical activity and intracellular sodium concentration in frog muscle.
1953,
Pubmed
Dick,
The activities and concentrations of sodium and potassium in toad oocytes.
1969,
Pubmed
HINKE,
The measurement of sodium and potassium activities in the squid axon by means of cation-selective glass micro-electrodes.
1961,
Pubmed
Ito,
Electrical characteristics of Triturus egg cells during cleavage.
1966,
Pubmed
JONES,
The culture of small aggregates of amphibian embryonic cells in vitro.
1963,
Pubmed
Kalt,
The relationship between cleavage and blastocoel formation in Xenopus laevis. II. Electron microscopic observations.
1971,
Pubmed
,
Xenbase
Kalt,
The relationship between cleavage and blastocoel formation in Xenopus laevis. I. Light microscopic observations.
1971,
Pubmed
,
Xenbase
KEYNES,
The intracellular calcium contents of some invertebrate nerves.
1956,
Pubmed
Kostellow,
Intracellular sodium ion concentration changes in the early amphibian embryo and the influence on nuclear metabolism.
1968,
Pubmed
Kroeger,
Regulation of gene action in insect development.
1966,
Pubmed
Kuchler,
The role of sodium and potassium in regulating amino acid accumulation and protein synthesis in LM-strain mouse fibroblasts.
1967,
Pubmed
MAENO,
Electrical characteristics and activation potential of Bufo eggs.
1959,
Pubmed
Morrill,
Water and electrolyte changes in amphibian eggs at ovulation.
1965,
Pubmed
Muir,
Variation in the nuclear sodium concentration of newt oocytes during maturation.
1972,
Pubmed
NAORA,
Some observations on differences in composition between the nucleus and cytoplasm of the frog oocyte.
1962,
Pubmed
Palmer,
Some bio-electric parameters of early Xenopus embryos.
1970,
Pubmed
,
Xenbase
PORTZEHL,
THE DEPENDENCE OF CONTRACTION AND RELAXATION OF MUSCLE FIBRES FROM THE CRAB MAIA SQUINADO ON THE INTERNAL CONCENTRATION OF FREE CALCIUM IONS.
1964,
Pubmed
Riemann,
Sodium and potassium in oocytes of Triturus cristatus.
1969,
Pubmed
Slack,
Intracellular and intercellular potentials in the early amphibian embryo.
1973,
Pubmed
,
Xenbase
Stableford,
A study of calcium in the early development of the amphibian embryo.
1967,
Pubmed
Thomas,
New design for sodium-sensitive glass micro-electrode.
1970,
Pubmed
Thomas,
Membrane current and intracellular sodium changes in a snail neurone during extrusion of injected sodium.
1969,
Pubmed
TUFT,
The uptake and distribution of water in the embryo of Xenopus laevis (Daudin).
1962,
Pubmed
,
Xenbase
Warren,
The determination of copper and magnesium in blood serum by high-resolution flame spectrophotometry.
1965,
Pubmed
Woodward,
Electrical signs of new membrane production during cleavage of Rana pipiens eggs.
1968,
Pubmed
