Fig. 2.

Cellular cAMP accumulation in acutely isolated mouse IMCD. Cells were preincubated with 1 mM 3-isobutyl-1-methylxanthine (IBMX) for 30 min and then incubated with medium alone, 5 mM EGTA, or BAPTA (1, 2, and 10 μM) for 30 min, followed by addition of 1 nM arginine vasopressin (AVP) for 5 min (n = 6 each data point). *P < 0.001 vs. AVP alone.