Infarction volume (B) by MCAO in rats (n = 8 in each group of different treatments). *The infarction volume 4 days after MCAO injury was significantly (P < 0.05) increased for MCAO-injured animals treated with an i.v. dose of normal saline (1 mL/kg) compared with MCAO sham controls. †The infarction volume 4 days after MCAO-injury was significantly decreased for MCAO-injured animals treated with an i.v. dose of agmatine (100 mg/kg) compared with vehicle controls. The photomicrograph (A) illustrates the infarction for a sham-operated rat, a MCAO rat treated with normal saline, and a MCAO rat treated with agmatine. Triphenyltetrazolium chloride staining shows severe infarctions characterized by pale TTC stains (whitish color) in the cortex and striatum on all brain sections examined.