Snake venom cardiotoxin can rapidly induce actin polymerization in intact platelets.
The action of Taiwan cobra (Naja naja atra) venom cardiotoxin on rabbit platelets at 37 degrees C was characterized by observing cytoskeletal alterations and cell lysis. At a concentration of 21.4 microM the toxin produced no cell lysis within 30 s, and less than 5% of the total lactate dehydrogenase activity of intact cells was detected in the suspending medium after the interaction had proceeded for 3 min. The extent of cell lysis was proportional to toxin concentration and interaction time. Before cell lysis, the toxin caused rapid incorporation of actin monomers into cross-linked actin filaments. The actin incorporation could be inhibited by either the presence of cytochalasin B or increased CaCl2 concentration in the suspending medium. However, addition of indomethacin did not influence the toxin-induced cytoskeletal change.
Liou
R F
RF
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China.
Chang
W C
WC
Chu
S T
ST
Chen
Y H
YH
D000199:Actins / Q000378:metabolism*; D000818:Animals; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D004179:Cobra Cardiotoxin Proteins / Q000494:pharmacology*; D003432:Cross-Linking Reagents / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D007700:Kinetics; D011108:Polymers; D011817:Rabbits
D000199:Actins; D004179:Cobra Cardiotoxin Proteins; D003432:Cross-Linking Reagents; D011108:Polymers