Coughlan et al. [105] did not find an effect of progesterone on BDNF expression in the brain of mice who received a single progesterone dose of 8 mg/kg at the onset of a stroke; Cekic et al. [106] reported that levels of BDNF, pro-BDNF, and TrkB were reduced in the brains of rats treated with an 8mg/kg intraperitoneal injection of progesterone at 1 h, as well as subcutaneous injections at 6 and 24 h, continuing every 24 h post-injury. This evidence concerns the gene BDNF and stroke disorder.