Interaction of gossypol with sperm macromolecules and enzymes.

The interaction of gossypol with sperm macromolecules is an important process for the gossypol action. It is of our interests to study the nature of this interaction in order to understand the mechanism of action of gossypol. Our experimental results support the thesis that gossypol inhibits sperm motility by blocking ATP production and utilization. The drug acts on the mitochondria, suppressing oxygen consumption, inhibiting pyruvate dehydrogenase and ATPase activities and probably on the motility apparatus by blocking dynein ATPase activity and preventing protein phosphorylation. The nature of the chemical bond in the interaction of gossypol and macromolecules is through the Schiff base formation and by the hydrophobic and nucleophilic attraction.