Figure 1: Dose- and time-dependent effects of annexin A5 (A5) on testosterone production in rat Leydig cells. The cells were treated with various concentrations of annexin A5 for 24 h ( a ) or cells were treated with 1 nmol l−1 of annexin A5 for different time points ( b ), then culture medium was collected and assayed for testosterone production by chemiluminescence assay. The data are presented as mean ± s.d. from three independent experiments performed in triplicate. **P < 0.01, compared with the control.