Group I and II metabotropic glutamate receptor expression in cultured rat spinal cord astrocytes

We have examined the development of expression of group I and II metabotrop ic glutamate receptors (mGluRs) in pure rat spinal cord astrocyte cultures, using immunocytological and calcium imaging techniques. mGluR1 alpha and m GluR2/3 antibodies were found to label roughly 10% of the total astrocyte p opulation at all time points examined, whereas mGluR5 was poorly expressed in our culture system. Results from intracellular Ca2+ imaging experiments, measured using fura-2 ratio imaging, suggest that 20% of these cultured as trocytes express functional group I mGluRs (mGluR1 and/or 5). Our results c ontrast with previously published work in cultured cortical astrocytes wher e mGluR5 and not mGluR1 is expressed, suggesting that cultured astrocytes f rom different parts of the CNS exhibit different patterns of mGluR expressi on. (C) 1999 Elsevier Science ireland Ltd. All rights reserved.