A 25-year-old woman complained of edema on her face and legs, rise of blood pressure up to 160/100 mm Hg and weakness. She fell ill 3 weeks after recovering from angina. Urinalysis data: protein of 0,5 g/l, erythrocytes of 17-20/field, leukocytes of 2-3/field, erythrocyte casts. What treatment should be initiated after specifying the diagnosis?