Effects of ryanoids on spontaneous and depolarization-evoked calcium release events in frog muscle

Biophysical Journal
Chiu Shuen HuiKeshore R Bidasee

Abstract

The effects of ryanoids on calcium sparks and transients were studied in voltage-clamped cut frog muscle fibers with a laser scanning confocal microscope. For each ryanoid employed, several sequential effects were observed, including: a), transient increases in spontaneous spark frequency; b), conversions of sparks to long-lasting steady glows; and c), occasional interruptions of the glows. The ratio of the amplitude of the glow induced by a ryanoid to that of the precursory spark followed the order: ryanodol > ryanodine > C(10)-O(eq)-glycyl-ryanodine > C(10)-O(eq)-beta-alanyl-ryanodol. This sequence of glow amplitudes parallels that of the subconductances induced by these ryanoids in single-channel studies, suggesting that the glows reflect Ca(2+) fluxes through semiopen calcium release channels. Ryanoids also abolished depolarization-evoked sparks elicited with small pulses, and transformed the calcium release during depolarization to a uniform nonsparking fluorescence signal. The ratio of this signal, averaged spatially, to that of the control followed the order: ryanodol < ryanodine < C(10)-O(eq)-glycyl-ryanodine < C(10)-O(eq)-beta-alanyl-ryanodol, implying an inverse relationship with the amplitudes of ryanoid-induced glow...Continue Reading

References

Nov 1, 1985·Proceedings of the National Academy of Sciences of the United States of America·S FleischerE A Fleer
Sep 1, 1987·The American Journal of Physiology·E RousseauG Meissner
Jan 1, 1988·Proceedings of the National Academy of Sciences of the United States of America·L HymelH Schindler
Jan 1, 1987·The Journal of General Physiology·M IrvingW K Chandler
Feb 1, 1996·Nature·M G KleinM F Schneider
Nov 15, 1996·The Journal of Physiology·I ParkerW G Wier
Jul 1, 1997·The Journal of Physiology·N Shirokova, E Ríos
Oct 9, 1998·The Journal of Physiology·N ShirokovaE Ríos
Jul 10, 1999·Pflügers Archiv : European journal of physiology·M DiFrancoJ L Vergara
Apr 12, 2000·Proceedings of the National Academy of Sciences of the United States of America·A GonzálezE Ríos
Jun 9, 2001·Circulation Research·S O MarxA R Marks
Jul 17, 2001·The Journal of Physiology·C S HuiH R Besch
May 7, 2002·Frontiers in Bioscience : a Journal and Virtual Library·Eduardo Ríos, Gustavo Brum

❮ Previous
Next ❯

Citations

Mar 8, 2007·Pflügers Archiv : European journal of physiology·László Csernoch
Apr 27, 2010·Pflügers Archiv : European journal of physiology·Josefina Ramos-FrancoMichael Fill

❮ 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.