TY - JOUR
T1 - Ca2+ dependence of inositol 1,4,5-trisphosphate 3-kinase activity in the cytosol fraction of pig coronary artery
AU - Yamaguchi, Koji
AU - Hirata, Masato
AU - Ishimatsu, Toyohiro
AU - Kuriyama, Hirosi
N1 - Funding Information:
Acknowledgements-This studyw ass upporteidn part by the funding from the Naito Foundation and bv a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan. We thank M. Ohara for reading the manuscript.
PY - 1989
Y1 - 1989
N2 - 1. The activity of inositol 1,4,5-trisphosphate 3-kinase in subcellular fractions of smooth muscles of the pig coronary artery was examined. 2. Incubation of [3H]inositol 1,4,5-trisphosphate (IP3) with muscle homogenates produced more polar 3H-radioactivity (probably as inositol 1,3,4,5-tetrakisphosphate, IP4) than IP3, in the Mg2+- and ATP-dependent manner, thereby indicating the presence of IP3 3-kinase activity in homogenates of the muscle. 3. Most of the kinase activity was present in the cytosol fraction. The enzyme activity was reversibly activated by Ca2+ with a half-maximal effective concentration of 2.5 × 10-7 M. 4. The calmodulin antagonists, W-7 and chlorpromazine inhibited the Ca2+-activated enzyme activity.
AB - 1. The activity of inositol 1,4,5-trisphosphate 3-kinase in subcellular fractions of smooth muscles of the pig coronary artery was examined. 2. Incubation of [3H]inositol 1,4,5-trisphosphate (IP3) with muscle homogenates produced more polar 3H-radioactivity (probably as inositol 1,3,4,5-tetrakisphosphate, IP4) than IP3, in the Mg2+- and ATP-dependent manner, thereby indicating the presence of IP3 3-kinase activity in homogenates of the muscle. 3. Most of the kinase activity was present in the cytosol fraction. The enzyme activity was reversibly activated by Ca2+ with a half-maximal effective concentration of 2.5 × 10-7 M. 4. The calmodulin antagonists, W-7 and chlorpromazine inhibited the Ca2+-activated enzyme activity.
UR - http://www.scopus.com/inward/record.url?scp=0024508221&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024508221&partnerID=8YFLogxK
U2 - 10.1016/0742-8413(89)90220-X
DO - 10.1016/0742-8413(89)90220-X
M3 - Article
AN - SCOPUS:0024508221
SN - 1367-8280
VL - 92
SP - 163
EP - 166
JO - Comparative biochemistry and physiology. C, Comparative pharmacology and toxicology
JF - Comparative biochemistry and physiology. C, Comparative pharmacology and toxicology
IS - 1
ER -