[125I]-Bolton Hunter Substance P Specific Binding Sites on Cortical Astrocytes from New Born Mouse in Primary Culture

The presence of substance P (SP) receptors has been demonstrated in adult mammalian CNS in binding studies performed with synaptosomes or membranes using 3H-SP or 125I-Bolton Hunter SP (125I-BHSP) (1,2). Moreover, the precise regional localisation of these sites has been shown by microdissection and by autoradiography (3,4,5,6). On the other hand, 125I-BHSP binding sites were found on intact cells from the brain of embryonic mouse or rat. Particular culture conditions allowed to reveal the occurrence of 125I-BHSP binding sites on neurons. However, these studies did not exclude a localisation of these binding sites on astrocytes as well. The present study was performed to look for the existence of SP receptors on glial cells (astrocytes) in primary culture from new-born mice.