Bisprasin, a Novel Ca2+ Releaser with Caffeine-Like Properties from a Marine Sponge, Dysideaspp., Acts on Ca2+-Induced Ca2+ Release Channels of Skeletal Muscle Sarcoplasmic Reticulum

Suzuki, Atsuko and Matsunaga, Kimihiro and Shin, Heejae and Tabudravu, Jioji N. and Shizuri , Yoshikazu and Ohizumi, Yasushi (2000) Bisprasin, a Novel Ca2+ Releaser with Caffeine-Like Properties from a Marine Sponge, Dysideaspp., Acts on Ca2+-Induced Ca2+ Release Channels of Skeletal Muscle Sarcoplasmic Reticulum. The Journal of Pharmacology and Experimental Therapeutics, 292 (2). pp. 725-730. ISSN 0022-3565

PDF - Published Version Restricted to Repository staff only Download (174kB) | Request a copy

Abstract

Bisprasin, a unique bromotyrosine derivative containing a disulfide linkage, was isolated from a marine sponge of Dysideaspp. This compound caused a concentration-dependent (from 10 to 30 μM) increase in the 45Ca2+ release from the heavy fraction of skeletal muscle sarcoplasmic reticulum (HSR) of rabbit skeletal muscle in the same way as does caffeine. The 50% effective concentrations of bisprasin and caffeine were approximately 18 μM and 1.2 mM, respectively, indicating that the45Ca2+-releasing activity of bisprasin was approximately 70 times more potent than that of caffeine in HSR. The bell-shaped profile of Ca2+ dependence for bisprasin was almost the same as that for caffeine. Typical blockers of Ca2+-induced Ca2+ release channels, such as Mg2+, procaine, and ruthenium red, inhibited markedly bisprasin- and caffeine-induced 45Ca2+ release from HSR. This compound, like caffeine, significantly enhanced [3H]ryanodine binding to HSR. Scatchard analysis of [3H]ryanodine binding to HSR revealed that bisprasin and caffeine decreased the KD value without affecting the Bmax value, suggesting that both the drugs facilitate the opening of ryanodine receptor channels. The bisprasin- and caffeine-induced increases in [3H]ryanodine binding were further enhanced by adenosine-5′-(β,γ-methylene)triphosphate. These results suggest that the pharmacological properties of bisprasin are almost similar to those of caffeine, except for its 70-fold higher potency. Here, we present the first report on the pharmacological properties of bisprasin, which, like caffeine, induces Ca2+ release from skeletal muscle SR mediated through the ryanodine receptor.

Item Type:	Journal Article
Subjects:	Q Science > QD Chemistry R Medicine > R Medicine (General)
Divisions:	Faculty of Science, Technology and Environment (FSTE) > School of Biological and Chemical Sciences
Depositing User:	Repo Editor
Date Deposited:	05 Jun 2017 22:27
Last Modified:	05 Jun 2017 22:28
URI:	https://repository.usp.ac.fj/id/eprint/9943

Actions (login required)

View Item