Recording of MBP, heart rate and blood flow, blood velocity, and blood mass of femoral skin during l-arginine (150 mg/kg for 30 min) infusion in one rat. Preinfusion values were recorded for >10 min before infusion to confirm stability, and the onset of recording is expressed as time 0. l-Arginine was infused from the 10-min to the 40-min period for 30 min, as indicated by the solid underbar.