Effects of semax and its Pro-Gly-Pro fragment on calcium homeostasis of neurons and their survival under conditions of glutamate toxicity.

Semax (100 microM) and its Pro-Gly-Pro fragment (20 and 100 microM) delayed the development of calcium dysregulation and reduction of the mitochondrial potential in cultured cerebellar granule cells under conditions of glutamate neurotoxicity. Incubation with these peptides improved neuronal survival by on average 30%. The neuroprotective effect of semax in cerebral ischemia/hypoxia can be due to improvement of mitochondrial resistance to "calcium" stress.