The purpose of this study is to examine whether the inhibition of aldosterone will result in lower excretion of protein via urine. The hypothesis is that if loss of protein is lowered, progression of renal disease with be slower than otherwise expected.

Patients with chronic renal disease are likely to progress to end stage renal disease with the need for renal replacement therapy. It is accepted that proteinuria is a surrogate measurement for progression. If proteinuria can be lowered we hope to prolong patients pre-dialysis phase. Our theory is that aldosterone inhibition will lead to this.

For a period of 8 weeks patients will be randomized to either aldosterone receptor inhibition with the drug eplerenone or control without. Blood pressures will be kept at the same level using other drugs.

Inclusion Criteria:

• Proteinuria > 500 mg/24 hours
• Hypertension or anti-hypertensive treatment

Exclusion Criteria:

• Diabetic nephropathy
• GFR< 20 ml/min
• P-potassium between 3,5 mmol/l and 5,0 mmol/l