scholarly journals Ionic basis of membrane potential in developing ectoderm of the Xenopus blastula.

1987 ◽  
Vol 393 (1) ◽  
pp. 525-544 ◽  
Author(s):  
C Baud
Keyword(s):  
Membrane Potential ◽  
Ionic Basis

scholarly journals The Ionic Basis of the Resting Potential in a Cross-Striated Muscle of the Aquatic Snail Lymnaea Stagnalis

1984 ◽  
Vol 108 (1) ◽  
pp. 305-314
Author(s):  
B. L. BREZDEN ◽  
D. R. GARDNER
Keyword(s):  
Membrane Potential ◽  
Lymnaea Stagnalis ◽  
Striated Muscle ◽  
Potassium Concentration ◽  
Muscle Cells ◽  
Resting Potential ◽  
Extracellular Potassium ◽  
Heart Ventricle ◽  
Sodium Permeability ◽  
Ionic Basis

The mean resting potential in the heart ventricle muscle cells of the freshwater snail Lymnaea stagnalis was found to be −61.2±3.5 (˙˙) mV (ranging from −56mV to −68mV). The average intracellular potassium concentration was estimated to be 51.5±14.6(˙˙) m (ranging from 27.8 m to 77.3 m). The membrane of the heart ventricle muscle cells appears to be permeable to both potassium and chloride, as changes in the extracellular concentration of either of these ions resulted in a change in the membrane potential. A ten-fold change in the extracellular potassium concentration was associated with a 50.4±3.8(˙˙) mV slope when the potassium concentration was above about 6 m. Deviations from the straight-line relation predicted for a potassium electrode could be accounted for by introducing a term for sodium permeability. The ionic basis of the membrane potential in these cells can be described by a modified form of the Goldman-Hodgkin- Katz equation.

scholarly journals K+ currents regulate the resting membrane potential, proliferation, and contractile responses in ventricular fibroblasts and myofibroblasts

2005 ◽  
Vol 288 (6) ◽  
pp. H2931-H2939 ◽  
Author(s):  
L. Chilton ◽  
S. Ohya ◽  
D. Freed ◽  
E. George ◽  
V. Drobic ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Reversal Potential ◽  
Mechanical Activity ◽  
Resting Membrane Potential ◽  
Whole Cell Patch Clamp ◽  
Voltage Dependent ◽  
Primary Determinant ◽  
Inwardly Rectifying ◽  
Low K ◽  
Ionic Basis

Despite the important roles played by ventricular fibroblasts and myofibroblasts in the formation and maintenance of the extracellular matrix, neither the ionic basis for membrane potential nor the effect of modulating membrane potential on function has been analyzed in detail. In this study, whole cell patch-clamp experiments were done using ventricular fibroblasts and myofibroblasts. Time- and voltage-dependent outward K+ currents were recorded at depolarized potentials, and an inwardly rectifying K+ (Kir) current was recorded near the resting membrane potential (RMP) and at more hyperpolarized potentials. The apparent reversal potential of Kir currents shifted to more positive potentials as the external K+ concentration ([K+]o) was raised, and this Kir current was blocked by 100–300 μM Ba2+. RT-PCR measurements showed that mRNA for Kir2.1 was expressed. Accordingly, we conclude that Kir current is a primary determinant of RMP in both fibroblasts and myofibroblasts. Changes in [K+]o influenced fibroblast membrane potential as well as proliferation and contractile functions. Recordings made with a voltage-sensitive dye, DiBAC3(4), showed that 1.5 mM [K+]o resulted in a hyperpolarization, whereas 20 mM [K+]o produced a depolarization. Low [K+]o (1.5 mM) enhanced myofibroblast number relative to control (5.4 mM [K+]o). In contrast, 20 mM [K+]o resulted in a significant reduction in myofibroblast number. In separate assays, 20 mM [K+]o significantly enhanced contraction of collagen I gels seeded with myofibroblasts compared with control mechanical activity in 5.4 mM [K+]o. In combination, these results show that ventricular fibroblasts and myofibroblasts express a variety of K+ channel α-subunits and demonstrate that Kir current can modulate RMP and alter essential physiological functions.

The ionic basis of the membrane potential in a rat glial cell line

1976 ◽  
Vol 104 (1) ◽  
pp. 71-92 ◽  
Author(s):  
Gary Kukes ◽  
Rafael Elul ◽  
Jean De Vellis
Keyword(s):  
Membrane Potential ◽  
Cell Line ◽  
Glial Cell ◽  
Ionic Basis

scholarly journals Ionic basis of resting membrane potential in frog taste cells.

1984 ◽  
Vol 34 (6) ◽  
pp. 973-983 ◽  
Author(s):  
Toshihide SATO ◽  
Kumiko SUGIMOTO ◽  
Yukio OKADA ◽  
Takenori MIYAMOTO
Keyword(s):  
Membrane Potential ◽  
Resting Membrane Potential ◽  
Taste Cells ◽  
Ionic Basis

scholarly journals Ionic Basis for Membrane Potential Resonance in Neurons of the Inferior Olive

Cell Reports ◽  
2016 ◽  
Vol 16 (4) ◽  
pp. 994-1004 ◽  
Author(s):  
Yoshiko Matsumoto-Makidono ◽  
Hisako Nakayama ◽  
Miwako Yamasaki ◽  
Taisuke Miyazaki ◽  
Kazuto Kobayashi ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Inferior Olive ◽  
Ionic Basis
Sign in / Sign up

Export Citation Format

Share Document