Exp Mol Med.  1999 Mar;31(1):25-29.

Effect of amino acids on inhibition of lactate dehydrogenase-X by gossypol

• Javed MH
• Khan MA

Abstract

Gossypol acetic acid (GAA) has been shown to have male antifertility effects, but there are pronounced differences among animal species. In the search of endogenous effector molecules, which interfere with the functions of GAA, we have studied the in vitro effect of various amino acids on the inhibition of the purified LDH-X by GAA. Histidine, cysteine and glycine were shown to block the effect of GAA. The effects of these amino acids were concentration dependent. Histidine and glycine protection was found to be complex type in which both the Km and Vmax were decreased compared to control. Arginine, glutamic acid, phenylalanine and valine were found to be ineffective against the inhibitory action of GAA.

Keyword

amino acids; goat; gossypol acetic acid; LDH-X; testes

MeSH Terms

Amino Acids/pharmacology*
Animal
Enzyme Inhibitors/pharmacology*
Goats
Gossypol/pharmacology
Gossypol/analogs & derivatives*
Isoenzymes
Lactate Dehydrogenase/antagonists & inhibitors*
Male
Spermatocidal Agents/pharmacology*
Testis/enzymology