Fig. 6.

P2Y₁ is expressed by dorsal spinal cord astrocytes. a, Result of RT-PCR performed on mRNA from embryonic spinal cord and dorsal spinal cord cultures using primers complementary to the rat P2Y₁ purinoceptor. PCR was performed on plasmid P2Y₁ as a positive control and on water RT-embryonic cord [−RT (e.c.)] and spinal cord cultures [−RT (c.c.)] as negative controls.b, Record of [Ca²⁺]_i in a neuron. 2-MeSADP (10 μm, 10 sec) was directly applied as indicated by the bottom black bar. The cell was then bathed in extracellular solution containing veratridine (10 μm) and no added TTX as indicated by the white bar. c, Record of [Ca²⁺]_i in an astrocyte onto which 2-MeSADP (10 μm, 10 sec) was directly applied (bottom black bar). After the return of [Ca²⁺]_i to the baseline level, veratridine (10 μm) was bath-applied as indicated by thewhite bar.