Abstract
1.
A study has been made of the action of heated cobra venom, a partially purified human pancreatic phospholipase A (phosphatide acyl-hydrolase, EC 3.1.1.4) and crude sea-snake venom on the phospholipids of human red cell ghosts and intact, washed erythrocytes.
2.
Marked variations were found between the action of the phospholipase A from these different sources on red cell ghosts and their actions on intact erythrocytes.
3.
Differences were also demonstrated between these three phospholipases in their ability to attack different phospholipids in the intact erythrocyte membrane.
4.
The pffect of plasma on the actions of these enzyme preparations on erythrocytes has been studied.
5.
Heparin has been shown to inhibit the phospholipase A activity of cobra venom and human pancreas.
6.
The relationship of these findings to the problem of the mechanism of haemolysis is discussed.