RESUMEN
Urinary kallikrein (reliable reflexion of its renal excretion) is studied in a large group of diabetic patients with and without nephropathy (again subdivided following Mogensen stages) and in hypertense non-diabetic patients. It is observed that the urinary excretion of kallikrein is independent of the type of diabetes (insulin or non-insulin dependent). There exists a clear difference in the behaviour of this enzyme, in diabetic patients with and without nephropathy, increasing in the former and decreasing in the latter (p less than 0.001). The decrease in urinary kallikrein is parallel to the existence of diabetic nephropathy with arterial hypertension. Urinary kallikrein in hypertense non-diabetic patients who are not treated with diuretics (furosemide) has a behaviour as in normal controls, but it is much higher in patients treated with captopril, being this finding of great importance since it can suggest new therapeutic approaches to diabetic nephropathy.