The presence of non-neuronal cells influences somatostatin release from cultured cerebral cortical cells.
We examined the effect of non-neuronal cells on somatostatin release from cultured cerebral cortical cells. Three culture models were used: (1) neuron-enriched cultures obtained from cortex of 17-day-old rat embryos and exposed to 10 microM cytosine arabinoside (Ara C) for 48 h between days 3 and 5 after plating; (2) whole cell cultures obtained by using the same protocol but untreated with Ara C; (3) glial primary cultures obtained from newborn rats. We studied: (i) the cellular composition of the cultures by using two astroglial markers: vimentin and glial fibrillary acidic protein (GFAP); (ii) the spontaneous and forskolin-stimulated somatostatin release. In 8-day-old cultures morphological data revealed that Ara C treatment reduced glial cells to 6%. At 7 and 10 days of culture somatostatin spontaneously released from Ara C-treated cells was higher than that measured from untreated cells. On the 17th day of culture, neuron-enriched cultures contained a lower amount of somatostatin than whole cell cultures. Forskolin elicited a dose-dependent release of somatostatin from whole cell cultures, but had no effect on neuron-enriched cultures. Astroglial released media (ARM) from glial primary cultures exposed to forskolin for 20 min induced somatostatin release from neuron-enriched cultures. HPLC analysis of endogenous amino acids of ARM showed that glutamate, glutamine, glycine and alanine were significantly increased after forskolin stimulation. Our results suggest a functional interaction between glial cells and neurons secreting somatostatin.
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D005576:Colforsin / Q000494:pharmacology; D003470:Culture Media; D003561:Cytarabine / Q000494:pharmacology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D009457:Neuroglia / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D013004:Somatostatin / Q000378:metabolism*; D013997:Time Factors; D014746:Vimentin / Q000032:analysis
D000596:Amino Acids; D003470:Culture Media; D005904:Glial Fibrillary Acidic Protein; D014746:Vimentin; D003561:Cytarabine; D005576:Colforsin; D013004:Somatostatin