Himehabu lectin, a novel inducer of Ca2+-release from the venom of the snake Trimeresurus okinavensis, in sarcoplasmic reticulum.
The lectin himehabu lectin (HHL) has recently been isolated from crude venom of the snake Trimeresurus okinavensis. Ca2+ -electrode and fluorescent Ca2+ -indicator experiments showed that HHL induced release of Ca2+ from the heavy fraction of skeletal muscle sarcoplasmic reticulum (HSR). The release of Ca2+ induced by caffeine from HSR was abolished by ryanodine, Mg2+ and ruthenium red, typical inhibitors of Ca2+ -release channels, whereas that induced by HHL was only partially reduced by these inhibitors. HHL, unlike caffeine, had no effect on [3H]ryanodine binding to HSR. These results suggest that HHL induces release of Ca2+ which is at least partially mediated through Ca2+ -release channels with novel pharmacological properties.
Hirata
Y
Y
Department of Pharmaceutical Molecular Biology, Faculty of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
Ito
M
M
Nikai
T
T
Kato
S
S
Komori
Y
Y
Sugiura
H
H
Ohizumi
Y
Y
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D003435:Crotalid Venoms / Q000737:chemistry* / Q000494:pharmacology*; D005453:Fluorescence; D037102:Lectins / Q000494:pharmacology*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D011817:Rabbits; D012433:Ryanodine / Q000378:metabolism; D019837:Ryanodine Receptor Calcium Release Channel / Q000187:drug effects / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism; D017841:Trimeresurus; D014316:Tritium
D003435:Crotalid Venoms; D037102:Lectins; D019837:Ryanodine Receptor Calcium Release Channel; D014316:Tritium; D012433:Ryanodine; D002118:Calcium