Inclusion Criteria:

• Patients diagnosed to have UC in the active stage based on clinical symptoms and findings from endoscopy
• Patients with pancolitis type or left-sided colitis type lesion of 15 cm or longer observed endoscopically
• Patients with Mayo score between 5 and 10
• Patients with Mayo sub-score (findings from flexible sigmoidoscopy) of 2 or 3
• Patients not having received any corticosteroids (referred to as steroids) (p.o., i.v., enema, suppository) within the past 6 weeks

Exclusion Criteria:

• Patients with a difficulty in peripheral vascular access
• Patients having received ACE inhibitor (at least 10 times of its half-life time for interval needed before initiating the treatment)
• Patients with toxic megacolon
• Patients with a malignant disease or its experience
• Patients with a severe cardiovascular disease (grade III or IV by the Classification of heart functions of the New York Heart Association (NYHA))
• Patients with a liver or kidney disease (AST(GOT) or ALT(GPT) or total bilirubin or creatinine level which is 2 or more times higher than the upper limit of normal (abbreviated as ULN, hereinafter)
• Patients suspected to have or having HBV or HCV or HIV or pathogenic bacteria
• Patients on anticoagulant therapy or with abnormality in the blood coagulation system (PT or PTT levels which are 1.5 or more times higher than ULN
• Pregnant women or patients with possible pregnancy
• Breast feeding women
• Patients weighing 40 kg or less
• Patients with hemoglobin level of less than 6.5 mmol/L (10.5 g/dL)
• Patients with platelet count of less than 150 x 103/mm3, 150 x 109/L (15 x 104/mm3)
• Patients with white blood cell count of less than 3.5 x 109/L (3,500/mm3)
• Patients with hypotension (with systolic blood pressure of 80 mmHg or less)