On the Mechanism of Action of Aminopterin.∗

  title={On the Mechanism of Action of Aminopterin.∗},
  author={Charles A. Nichol and Arnold deM. Welch},
  journal={Proceedings of the Society for Experimental Biology and Medicine},
  pages={403 - 411}
  • C. A. Nichol, A. D. Welch
  • Published 1 June 1950
  • Biology
  • Proceedings of the Society for Experimental Biology and Medicine
Summary Rat liver slices form from synthetic folic acid (PGA) a factor (CF) utilized for growth by Leuconostoc citrovorum; this conversion is inhibited by aminopterin. In rats given PGA, a similar inhibition of the synthesis of CF is shown by a marked decrease in the urinary excretion of CF following the administration of aminopterin. The antagonist not only prevents the metabolic alteration of PGA but also competes with the product (CF) derived from PGA. The lethal action in rats of… 

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