GROWTH OF NAEGLERIA WITH INSULIN

The growth factor insulin was added to axenic cultures of pathogenic N aegleria fowleri and nonpathogenic Naegleria gruberi to determine whet her it would enhance the growth of amebae. The growth of N. fowleri wa s not affected by the presence of insulin; however, N. gruberi was inh ibited by 100 mug/ml insulin. Based on these results, N. fowleri could tolerate the levels of insulin in the brain and especially that of th e olfactory bulbs, the tissues invaded, which have much higher concent rations of insulin than the serum.