Polyamines and the growth of leishmanial parasites.

The relation between the grown of leishmanial parasites and polyamine biosynthesis was studied. Polyamines, mainly putrescine and spermidine, accumulated in macrophages infected with Leishmania tropica major promastigotes grown in vitro. Similar results were obtained, when tissues of BALB/C mice infected with L. tropica major were examined. A consistent increase in cellular putrescine and spermidine levels was observed in infected skin and spleen. With the accumulation of putrescine, a concomitant increase in ornithine decarboxylase activity was detected in growing leishmanial promastigotes and in macrophages supporting the growth of leishmanial amastigotes. An increase in the activity of ornithine decarboxylase was also observed in Leishmania-infected skin and spleen from BALB/C mice.