Table 1.

Effect of a P2Y₁ receptor antagonist MRS2500, a P2 receptor antagonist suramin, a PKC inhibitor staurosporine, and depletion of extracellular Ca²⁺ on (a) 2-MeSADP- or (b) UDP-induced transient [Ca²⁺]_i rise in the mouse islet and beta-TC6 cells

	+MRS2500		+Suramin	+Staurosporine	No extracellular Ca2+
	10 μM	30 μM	100 μM	1 μM
a
	% of control (100 μM 2-MeSADP alone)
Mouse islet	49 ± 11 (n = 6)*	23 ± 8 (n = 5)*	15 ± 7 (n = 5)*	80 ± 13 (n = 3)	80 ± 11 (n = 7)
Beta-TC6 cells	35 ± 4 (n = 14)*	24 ± 3 (n = 16)*	49 ± 10 (n = 31)*	113 ± 11 (n = 24)	51 ± 12 (n = 30)*
b
	% of control (200 μM UDP alone)
Mouse islet			11 ± 6 (n  = 4)*	120 ± 28 (n = 5)	112 ± 23 (n = 6)
Beta-TC6 cells			51 ± 6 (n = 15)*	82 ± 9 (n = 32)	65 ± 9 (n = 24)*

MRS2500 and suramin were added with the nucleotides simultaneously to the culture of the islet or to beta-TC6 cells in the presence of 5.5 mM glucose. The islet and beta-TC6 cells were preincubated with staurosporine for 20 min (mean ± SE)

*P < 0.05