Extracellular potassium accumulation in voltage-clamped frog ventricular muscle

The Journal of Physiology
L Cleemann, M Morad

Abstract

1. Application of voltage clamp pulses (1--10 sec) to frog ventricular strips causes temporary changes in the extracellular K concentration. 2. The changes in the extracellular K concentration can be estimated from (a) slowly decaying post-clamp after-potentials, (b) changes in the action potential duration, and (c) measurements with a K-selective micro-electrode. 3. The depolarization of the resting potential and the shortening of the action potential are present in approximately the same proportions during voltage-clamp induced extracellular K accumulation and during perfusion with a K-ricn Ringer solution but small consistent differences are noticed. 4. The measurements of the after-potential, the action potential shortening, and the K-electrode response were analysed as indicators of extracellular K+ activity and it was concluded that the after-potential provides the most convenient and reliable estimate of the absolute magnitude of the voltage-clamp induced extracellular K accumulation. 5. The depolarizing after-potentials decay more slowly than the hyperpolarizing after-potentials but it is found that this reflects the selectivity of the membrane to K+ concentrations as predicted by the Nernst or the Goldman equations. 6....Continue Reading

Citations

Jan 1, 1986·The Journal of Membrane Biology·Y Tourneur
Jul 1, 1982·IEEE Transactions on Bio-medical Engineering·J P Drouhard, F A Roberge
Sep 1, 1980·Pflügers Archiv : European journal of physiology·D DiFrancescoW Trautwein
Apr 1, 1980·Pflügers Archiv : European journal of physiology·J VereeckeE Carmeliet
Sep 1, 1983·Pflügers Archiv : European journal of physiology·T Klitzner, M Morad
Oct 1, 1985·Pflügers Archiv : European journal of physiology·L Tung, M Morad
Oct 1, 1980·Circulation Research·A VleugelsE Carmeliet
Dec 1, 1984·Pflügers Archiv : European journal of physiology·D DiFrancescoS Visentin
Aug 12, 1999·Clinical and Experimental Allergy : Journal of the British Society for Allergy and Clinical Immunology·Y G Yap, A J Camm
Sep 1, 1983·Pflügers Archiv : European journal of physiology·T Klitzner, M Morad

❮ 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.

Hereditary Sensory Autonomic Neuropathy

Hereditary Sensory Autonomic Neuropathies are a group of inherited neurodegenerative disorders characterized clinically by loss of sensation and autonomic dysfunction. Here is the latest research on these neuropathies.

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.

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.

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.

Landau-Kleffner Syndrome

Landau Kleffner syndrome (LKS), also called infantile acquired aphasia, acquired epileptic aphasia, or aphasia with convulsive disorder, is a rare childhood neurological syndrome characterized by the sudden or gradual development of aphasia (the inability to understand or express language) and an abnormal electroencephalogram. Discover the latest research on LKS 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.

Regulation of Vocal-Motor Plasticity

Dopaminergic projections to the basal ganglia and nucleus accumbens shape the learning and plasticity of motivated behaviors across species including the regulation of vocal-motor plasticity and performance in songbirds. Discover the latest research on the regulation of vocal-motor plasticity here.