Figure 4.

Oscillations of P2Y₁R-mediated Ca ²⁺ responses are prevented by inhibiting protein kinase C. a, Record of fura-2 emission ratios from a single cell. 2-MeSADP (10 μm, 5 sec, arrows) was applied at a rate of 1 min ^-1 before or during bath application of the Gö6850 (1 μm; white bar). The application of Gö6850 began 20 min before the start of the train of 2-MeSADP shown on the right. b, Histogram showing the average amplitude of -1, index, and +1 responses for 2-MeSADP-evoked responses without (black bars; n = 9 cells) or with bath-applied Gö6850 (white bars; n = 5 cells).*p < 0.01; Student's t test. c, Histogram showing the average amplitude of -1, index, and +1 responses for P2Y₁R-mediated responses evoked at a rate of 1 min ^-1 by submaximal concentrations of 2-MeSADP (20 nm) without (black bars; n = 25 index responses from 6 cells) or with bath-applied Gö6850 (white bars; n = 57 index responses from 4 cells).*p < 0.01; Student's t test. d, 2-MeSADP applications (10 μm, 5 sec, 1 min ^-1, arrows) made before or during bath administration of Bis. V (1 μm) are shown for another astrocyte (representative of the 3 cells tested).