Also found in: Medical.
substances of plant, animal, or microbial origin that injure the membranes of red blood cells and cause them to undergo hemolysis. Hemotoxins are mainly enzymes like lecithinases or phospholipases, which split phospholipids in the membranes of red blood cells, or saponin-like substances that act on another component of the membrane, cholesterol. Hemotoxins may be of microbial origin (from staphylococci, streptococci, and so forth), plant origin (tox-albumins, ricin, crotin, saponin, and abrin), or animal origin. The latter include arachnolysins of certain spiders (such as Latrodectus, Atrax, and Lycosa), hemotoxins of parasitic worms (Dibothriocephalus), and snake venoms, especially those of snakes from the families Viperidae and Crotalidae. The red blood cells of different animal species vary in sensitivity to the same hemotoxin. For example, snake venoms (like cobra venom) lyse the red blood cells of guinea pigs, dogs, and man but not those of cattle, sheep, and goats. Lecithins and cholesterol in large doses block the action of hemotoxins.
KH. KH. PLANEL’ES