Cyclic Guanosine Monophosphate in Primary Cultures of Glial Cells

Abstract

CGMP was found in glial cell primary cultures obtained by newborn mouse brain hemisphere dissociation. Its basal level (0.52 pmol/mg cell protein) was as high as that in adult mouse brain cortex but 10 times lower than in cerebellum. When glia were grown in the presence of dB[dibutyryl]cAMP, astrocytes changed their morphology; cGMP level increased and reached about 8-10 times the basal value. This increase was dose dependent with cAMP and was enhanced by the presence of 5mM theophylline. Two hypotheses are discussed: a direct action of cAMP on glial cGMP metabolism or an indirect one on the protein activator of cGMP phosphodiesterase.