Effect of lixisenatide treatment on apoptosis and contractility of isolated cardiomyocytes. (A) Caspase-3/7 activity is reduced in cardiomyocytes incubated with either insulin or lixisenatide (each at 100 nM). (B, C) Lixisenatide (Lixi) but not GLP-1 (6–36)-amide increases fractional shortening. Isoprenaline (Iso, 1nM) served as positive control. (D). Cardiomyocytes isolated from GLP-1 receptor knockout mice respond to lixisenatide. Mean values and SEM are given. In the fractional shortening experiments, n > 18 single cardiomyocytes were measured for each group.