A bioassay for cobra cardiotoxin activity using semi-isolated cockroach heart.
A semi-isolated cockroach heart preparation was used to rapidly determine the activity of cobra cardiotoxin, monitored as a direct response on heart rate. This preparation produced a dose-response curve in the presence of active cardiotoxin and demonstrated that cardiotoxin retained its biological activity after boiling, although cardiotoxin activity was destroyed by heating in the presence of dithiothreitol. Experiments that cross-linked radiolabeled cardiotoxin to solubilized cockroach heart membranes suggested that cardiotoxin bound specifically to a 59,000 mol. wt membrane protein in this tissue.
Klowden
M J
MJ
Division of Entomology, University of Idaho, Moscow 83843.
Vitale
A J
AJ
Trumble
M J
MJ
Wesson
C R
CR
Trumble
W R
WR
D000818:Animals; D001681:Biological Assay; D004179:Cobra Cardiotoxin Proteins / Q000032:analysis* / Q000378:metabolism / Q000494:pharmacology; D003058:Cockroaches / Q000187:drug effects*; D003432:Cross-Linking Reagents; D006339:Heart Rate / Q000187:drug effects*; D008565:Membrane Proteins / Q000378:metabolism; D008970:Molecular Weight; D009206:Myocardium / Q000378:metabolism; D013388:Succinimides
D004179:Cobra Cardiotoxin Proteins; D003432:Cross-Linking Reagents; D008565:Membrane Proteins; D013388:Succinimides; C019358:disuccinimidyl suberate