The glia-glia, glia-neuron interactions are very complex and have not yet been clearly understood. Microglia gain reactivity in almost every type of brain insult and by affecting astrocytes and neurons, they determine the fate of damaged brain. In the present study we aimed to see the effect of stimulated microglia on nNOS and iNOS expression of astrocytes. The microglia cultures were stimulated with zymosanA and astrocytes were treated with the medium of microglia for 48 h. The results revealed that the astrocytes treated with microglia medium expressed more nNOS and iNOS than the ones treated with normal medium.