PMID: 6408607Apr 1, 1983Paper

How elevated extracellular Ca2+ inhibits quantal acetylcholine release at frog neuromuscular junctions in high K+

Pflügers Archiv : European journal of physiology
W van der Kloot, R Latta

Abstract

It is known that when end-plates partially depolarized in elevated [K+]o are exposed to an increase in [Ca2+]o there is a decrease in the min.e.p.p. frequency. Two hypotheses to account for the observations are: (1) a rise in [Ca2+]i inhibits m.e.p.p. generation; (2) the divalent metal ions decrease the surface potential on the nerve terminal and thereby increase the voltage drop in the membrane, depressing Ca2+ influx. In preparations in elevated [K+]o and [Ca2+]o, the m.e.p.p. frequency is increased further by additional depolarization, by Ca2+ ionophores, by increasing the tonicity of the extracellular solution, and by replacing the NaCl in the external solution with LiCl. All of these treatments are thought to further increase [Ca2+]i. Ba2+ and Sr2+ produce effects like Ca2+. However, if the increase in [Ca2+]o is compensated by a decrease [Na+]o sufficient to leave the surface potential unchanged, there is little alteration in m.e.p.p. frequency.

References

Mar 1, 1975·The Journal of Physiology·A C Crawford
Feb 20, 1975·Nature·D I Devore, W L Nastuk
Nov 1, 1975·Life Sciences·H E Statham, C J Duncan
Aug 5, 1967·Nature·B Katz, R Miledi
Mar 1, 1974·Proceedings of the National Academy of Sciences of the United States of America·R U Muller, A Finkelstein
Jan 31, 1967·Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character·B Katz, R Miledi
Dec 1, 1971·The Journal of General Physiology·S G McLaughlinG Eisenman
Jul 1, 1980·Pflügers Archiv : European journal of physiology·Y Ohta, K Kuba

❮ 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.