Figure 3From: Multiple P2Y receptors couple to calcium-dependent, chloride channels in smooth muscle cells of the rat pulmonary arteryThe amplitude and frequency of oscillating currents induced by P2Y receptor agonists. (a) The mean amplitude of oscillating currents induced by ATP, UTP and UDP (10-4 M) was measured over successive 30 s intervals for 4 min in smooth muscle cells isolated from SPA and voltage-clamped at -50 mV. 0.5 = the first 30 s of agonist application, 1 = 30 – 60 s, and so on. (b) The frequency of the oscillations in the same cells was measured over successive 1 min intervals. 1 = the first min of agonist application, 2 = the second min, and so on. Vertical bars represent s.e.mean. The number of cells for each agonist is shown in parentheses. * P < 0.05 for amplitude of peak current at 30 s versus that at 2:30, 3:00, 3:30 and 4:00 min; ** P < 0.01 for 30 s versus 3:30 and 4:00 min.Back to article page