The Effect of Ethanol on the Membrane Permeability to Sodium and Potassium Ions in Frog Muscle Fibres

2009 ◽  
Vol 25 (1) ◽  
pp. 54-64 ◽  
Author(s):  
E. Knutsson ◽  
S. Katz
Keyword(s):  
Membrane Permeability ◽  
Frog Muscle ◽  
Muscle Fibres ◽  
Potassium Ions ◽  
Sodium And Potassium

Binding of calcium ions to cell membrane isolated from bullfrog skeletal muscle

1964 ◽  
Vol 207 (2) ◽  
pp. 509-512 ◽  
Author(s):  
K. Koketsu ◽  
R. Kitamura ◽  
R. Tanaka
Keyword(s):  
Skeletal Muscle ◽  
Membrane Potential ◽  
Cell Membrane ◽  
Membrane Permeability ◽  
Calcium Ions ◽  
Cytoplasmic Membrane ◽  
Muscle Fibers ◽  
Potassium Ions ◽  
Chloroform Methanol ◽  
Sodium And Potassium

The membrane fragments of bullfrog skeletal muscle fibers were isolated by a modification of the method of Kono and Colowick (1961). Radiocalcium ions were bound to these isolated membrane fragments, and the binding of calcium ions was impeded by both sodium and potassium ions. The extractable portion of the isolated membrane fragments with chloroform-methanol mixture bound calcium ions whereas no appreciable binding of calcium ions was observed with the extracted residue. The results suggested that the binding of calcium ions takes place on the lipid or lipoprotein of the so-called cytoplasmic membrane which plays an important role in regulating the membrane permeability and the membrane potential.

scholarly journals Potentiometric measurement of membrane action potentials in frog muscle fibres

1966 ◽  
Vol 183 (1) ◽  
pp. 152-166 ◽  
Author(s):  
B. Frankenhaeuser ◽  
B. D. Lindley ◽  
R. S. Smith
Keyword(s):  
Action Potentials ◽  
Frog Muscle ◽  
Muscle Fibres ◽  
Membrane Action ◽  
Potentiometric Measurement

scholarly journals Changes in the Membrane Permeability of Frog's Sartorius Muscle Fibers in Ca-Free EDTA Solution

1963 ◽  
Vol 47 (2) ◽  
pp. 379-392 ◽  
Author(s):  
H. Kimizuka ◽  
K. Koketsu
Keyword(s):  
Membrane Permeability ◽  
Chloride Content ◽  
Chloride Ions ◽  
Sartorius Muscle ◽  
Constant Field ◽  
Sodium Influx ◽  
Sodium Potassium ◽  
Edta Solution ◽  
Frog Sartorius ◽  
Sodium And Potassium

The changes in the membrane permeability to sodium, potassium, and chloride ions as well as the changes in the intracellular concentration of these ions were studied on frog sartorius muscles in Ca-free EDTA solution. It was found that the rate constants for potassium and chloride efflux became almost constant within 10 minutes in the absence of external calcium ions, that for potassium increasing to 1.5 to 2 times normal and that for chloride decreasing about one-half. The sodium influx in Ca-free EDTA solution, between 30 and 40 minutes, was about 4 times that in Ringer's solution. The intracellular sodium and potassium contents did not change appreciably but the intracellular chloride content had increased to about 4 times normal after 40 minutes. By applying the constant field theory to these results, it was concluded that (a) PCl did not change appreciably whereas PK decreased to a level that, in the interval between 10 and 40 minutes, was about one-half normal, (b) PNa increased until between 30 and 40 minutes it was about 8 times normal. The low value of the membrane potential between 30 and 40 minutes was explained in terms of the changes in the membrane permeability and the intracellular ion concentrations. The mechanism for membrane depolarization in this solution was briefly discussed.

Sodium and Potassium Fluxes in the Abdominal Nerve Cord of the Cockroach, Periplaneta Americana L

1961 ◽  
Vol 38 (2) ◽  
pp. 315-322
Author(s):  
J. E. TREHERNE
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Nerve Cord ◽  
Periplaneta Americana ◽  
Unit Area ◽  
Potassium Ions ◽  
Sodium Ions ◽  
Nerve Sheath ◽  
The Central Nervous System ◽  
Sodium And Potassium

1. The influx of sodium and potassium ions into the central nervous system of Periplaneta americana has been studied by measuring the increase in radioactivity within the abdominal nerve cord following the injection of 24NA and 42K. into the haemolymph. 2. The calculated influx of sodium ions was approximately 320 mM./l. of nerve cord water/hr. and of potassium ions was 312 mM./l. of nerve cord water/hr. These values are very approximately equivalent to an influx per unit area of nerve cord surface of 13.9 x 10-2 M cm. -2 sec.-1 for sodium and 13.5 x 10-12 M cm. -2 sec.-1 for potassium ions. 3. The relatively rapid influxes of these ions are discussed in relation to the postulated function of the nerve sheath as a diffusion barrier. It is suggested that a dynamic steady state rather than a static impermeability must exist across the sheath surrounding the central nervous system in this insect.

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