Antibiotics contain (0.4 g procaine benzyl penicillin, 0.5 g dihydrostreptomycin sulphate (Norbrook Laboratories, UK) were administered prophylactically for three days post-surgery. Post-surgical analgesia was maintained with intramuscular injection of flunixin meglumine (1 mg/kg; Mavlab, Brisbane, Australia) at the start of surgery, and then 4 and 16 hours post-surgery.Experiments commenced at least two weeks after surgery and were conducted on conscious sheep. On the day prior to the experiments, arterial and venous cannulae were inserted as described previously [7,8]. Cannulae were connected to pressure transducers (CDX III. Cobe, Denver, CO, USA) tied to the wool on the sheeps’ backs. Pressures were adjusted to account for the height of the transducers above the heart.

A bladder catheter was inserted for urine collection.Data from the flow probes were collected via flow-meters (Transonic Systems Inc., Ithaca, NY, USA). The use of chronically implanted transit-time flow probes for the accurate measurement of regional blood flow has been described previously [15,16]. Analog signals for mean arterial pressure (MAP), central venous pressure (CVP), cardiac output (CO) and RBFs were collected at 100 Hz for 10 seconds at 1 minute intervals throughout the experiment on a computer using custom written software. For the figures, data were grouped into means values for every 15 minutes.Experimental protocolBaseline measurements were collected for a 120 minute control period before the induction of sepsis by intravenous injection of live Escherichia coli (3 �� 109 colony forming units) over five minutes at 01.

00 AM. Approximately 8 to 12 hours after the initial bolus, animals typically reached the pre-defined cardiovascular criteria for randomization (hyperdynamic sepsis): 10% decrease in MAP, 50% increase in heart rate and 30% increase in CO.After reaching the criteria for septic shock, animals were observed for a 120 minute pre-treatment period before being randomly assigned to receive a six-hour intravenous infusion of either Ang II (55 �� 78 ng/kg/min, range 4.25 to 450 ng/kg/min) or vehicle (saline). The dose of Ang II was titrated to maintain MAP at the pre-sepsis control level, with two of the sheep requiring increases in infusion rate during the treatment period to maintain MAP.

Blood samples were taken the day before the induction of sepsis, at the end of the sepsis control period, and every two hours during the six-hour treatment period. Urine was collected and sampled every two hours throughout the experiment from the bladder catheter using an automated fraction collector. The creatinine clearance (CreatinineUrine/CreatininePlasma Anacetrapib �� UrineVolume/time) and fractional excretion of sodium (SodiumUrine/SodiumPlasma �� CreatininePlasma/CreatinineUrine �� 100) were calculated.