Figure 3. H9c2 cell Response to Vasopressin (VP).

A typical cell responding to a 1 nM VP increases [Ca²⁺]_i (A) to reach a peak [Ca²⁺]_i (B). [Ca²⁺]_i then begins an exponential recovery phase until reaching a plateau of increased [Ca²⁺] (C), that may or may not show a second [Ca²⁺]_i peak. The total Ca²⁺ response to agonist can be estimated by calculating the area under the Ca²⁺ trace (D, shaded black).