RESPONSE TO ORAL PROTEIN LOAD IN DIABETIC S WITH EARLY NEPHROPATHY AND PATIENTS WITH GLOMERULONEPHRITIS

In this study, we assessed glomerular filtration rate (GFR) renal plas ma flow (RPF), renal functional reserve (RFR) and hormonal response be fore and after an oral lactoprotein load (OPL) in 7 healthy young volu nteers with normal renal function, 13 patients with secondary glomerul oscelerosis and 8 type 1 diabetics with incipient nephropathy (microal buminuria 30-300 mg/24 hours in most determinations). Inulin and para- aminohippuric clearances and RFR were determined. Plasma levels of ren in, aldosterone, glucagon, HGH, cortisol, atrial natriuretic peptide, vasopressin and PGE2 were mesured. After OPL live observed a significa nt increase of GFR in healthy controls and in secondary glomeruloscler osis with RFR of 28 mil/min in both, but no increase in diabetic patie nts with RFR of 12 ml/min. Basal fraction filtration was significantly higher in incipient diabetic nephropathy, than in the control group a nd did not increase after OPL. Basal glucagon was significantly higher in diabetic patients but it did not increase after OPL as in healthy control and glomerulosclerosis patients. The OPL significantly increas ed GFR in controls and glomerulosclerosis patients but not in incipien t diabetic nephropathy. Diabetic patients have a higher filtration fra ction than controls or patients with glomerulosclerosis indicating glo merular hyperfiltration. Glucagon was significantly higher in diabetic patients and did not increase after OPL, contrary to what was observe d in the other two groups suggesting it may play an important role in glomerular hyperfiltration.