Dantrolene sodium increases calcium binding by human recombinant cardiac calsequestrin and calcium loading by sheep cardiac sarcoplasmic reticulum.

Aim: Dantrolene interacts with ryanodine receptors in skeletal and cardiac muscle affecting sarcoplasmic reticulum calcium release. Since dantrolene is lipophilic it could also affect intra-sarcoplasmic reticulum calcium handling proteins such as calsequestrin. This study investigated whether dantrolene (1-30 µmol/L) alters the polymerization state and the calcium binding capacity of recombinant cardiac calsequestrin and cardiac sarcoplasmic reticulum calcium handling.

The effects of Suramin on Ca activated force and sarcoplasmic reticulum Ca release in skinned fast-twitch skeletal muscle fibers of the rat.

Suramin has long been used in the treatment of various human diseases. Intravenous infusions of Suramin are commonly administered to patients over extended periods of time but there are a number of significant contraindications with peripheral muscle weakness being one of the most frequently reported. Previous work has shown that even after a single infusion (300 mg kg) Suramin remains in skeletal muscle in effective concentrations (11.