The influence of chlorpromazine on lipoxidases.

Chlorpromazine was found to inhibit oxygen consumption by lipoxidase from soybean and from blood platelets. The inhibition of 15-lipoxidase (linoleate:oxygen oxidoreductase, EC 1.13.11.12) (from soybean) depends on substrate concentration. IC50 values for this inhibition were 50-150 muM chlorpromazine at an arachidonic acid concentration of 20-300 muM. Inhibition of crude 12-lipoxidase preparation (100 000 X g supernatant from horse platelet homogenate) was weaker than 15-lipoxidase. IC50 at the arachidonic acid concentration of 100 muM was about 1000 muM chlorpromazine.