Membrane electrical properties of frog slow muscle fibres

The Journal of Physiology
W F Gilly, C S Hui

Abstract

1. Pyriformis slow (and sartorius twitch) fibres from Rana temporaria were studied with a three-micro-electrode voltage-clamp technique to obtain an approximate measurement of membrane current density at a fibre end. In most experiments, a modified Ringer solution containing 2H20 and 230 mM-sucrose was used to reduce movement. 2. Linear membrane properties of slow fibres obtained with this method are consistent with results from previous studies. Measured Cm (microF/cm2) increases with fibre diameter in a manner consistent with a tubular location of part of the fibre capacitance. 3. Voltage steps to -50mV and more positive potentials result in outward membrane currents in both slow and twitch fibres. These currents develop along similar sigmoid time courses and are blocked by tetraethylammonium (TEA+) ions. The reversal potential for delayed current channels in slow fibres varies with external K+ concentration, suggesting that the delayed current in slow fibres, as in twitch, is carried by K+ ions. 4. Maximum GK,GK, in slow fibres is an order of magnitude smaller than twitch fibres. The steady-state GK-V curve of slow fibres is very broad (e-fold for approximately 15 mV), saturating at very positive voltages, whereas the GK of ...Continue Reading

Citations

Jun 5, 2003·Experimental Neurology·Miguel HuertaBenjamin Trujillo-Hernández
Dec 6, 2001·Brain Research. Brain Research Protocols·C VásquezB Trujillo-Hernández
Jan 1, 1985·Progress in Biophysics and Molecular Biology·J CailléO Rougier
Apr 1, 1988·Journal of Ultrastructure and Molecular Structure Research·V VermaH P Richter
Sep 1, 1989·Pflügers Archiv : European journal of physiology·L SzczupakO D Uchitel
Jan 1, 1990·Journal of Neurobiology·A A Herrera, M J Werle
Jan 1, 1997·The American Journal of Physiology·M HuertaC Vásquez

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.