PMID: 8967964Dec 1, 1996Paper

Activation of the skeletal muscle ryanodine receptor by suramin and suramin analogs

Molecular Pharmacology
M HoheneggerM Freissmuth

Abstract

Ca2+ release from skeletal muscle sarcoplasmic reticulum is activated by adenine nucleotides and suramin. Because suramin is known to interact with ATP-binding enzymes and ATP receptors (P2-purinergic receptors), the stimulation by suramin has been postulated to occur via the adenine nucleotide-binding site of the ryanodine receptor/Ca2+-release channel. We tested this hypothesis using suramin and the following suramin analogs: NF037, NF018, NF023, and NF007. The suramin analogs stimulate the binding of [3H]ryanodine binding to sarcoplasmic reticulum membranes with the following rank order of potency: suramin (EC50 = approximately 60 microM) > NF037 (EC50 = approximately 150 microM) > NF018 > NF023 > NF007. The suramin-induced stimulation occurs via a myoplasmic binding site on the ryanodine receptor as confirmed by binding experiments and single-channel recordings with the purified protein. This binding site is different than that for ATP, a conclusion that is supported by the following observations: (i) Suramin stimulates the association rate and inhibits the dissociation rate of [3H]ryanodine, whereas ATP analogs increase only the on-rate. (ii) In the presence of suramin but not of ATP analogs, [3H]ryanodine binding is resis...Continue Reading

Related Concepts

Related Feeds

Anthelmintics (ASM)

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. Discover the latest research on anthelmintics here.

African Trypanosomiasis

African trypanosomiasis, also known as sleeping sickness, is an insect-borne parasitic disease of humans and other animals. It is caused by protozoa of the species Trypanosoma brucei and almost invariably progresses to death unless treated. Discover the latest research on African trypanosomiasis here.

Anthelmintics

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. Discover the latest research on anthelmintics here.