Open AccessThe Mode of Inhibitory Action of a-Mangostin, a Novel Inhibitor, on the Sarcoplasmic Reticulum Ca2+-Pumping ATPase from Rabbit Skeletal Muscle
Author(s) -
KenIchi Furukawa,
Kazuki Shibusawa,
Nattaya Chairungsrilerd,
Tomihisa Ohta,
Shigeo Nozoe,
Yasushi Ohizumi
Publication year - 1996
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.71.337
Subject(s) - endoplasmic reticulum , inhibitory postsynaptic potential , rabbit (cipher) , atpase , skeletal muscle , chemistry , microbiology and biotechnology , pharmacology , endocrinology , biology , biochemistry , enzyme , computer science , computer security
alpha-Mangostin, the principal ingredient of the fruit hull of Garcinia mangostana, caused a concentration-dependent decrease in the activities of both Ca(2+)-ATPase and Ca(2+)-transport of the sarcoplasmic reticulum from rabbit skeletal muscle with an IC50 value of 5 microM. Neither Ca2+ release nor other enzyme activities were affected by alpha-mangostin. Kinetic analysis of the inhibitory effects of alpha-mangostin on Ca(2+)-ATPase suggests that the inhibition of the ATPase is a noncompetitive-type with respect to ATP or Ca2+. alpha-Mangostin may become a useful pharmacological tool for clarifying the physiological functions of Ca(2+)-pumping ATPase and sarcoplasmic reticulum.