SHORT-TERM CLINICAL-TRIAL OF ENZOYL]-4-PIPERIDYL)-3,4-DIHYDRO-2(1H)-QUINOLINONE IN PATIENTS WITH DIABETIC NEPHROPATHY - POSSIBLE EFFECTIVENESS OF THE SPECIFIC VASOPRESSIN V1 RECEPTOR ANTAGONIST FOR REDUCING ALBUMINURIA IN PATIENTS WITH NON-INSULIN-DEPENDENT DIABETES-MELLITUS

We investigated the role of arginine vasopressin (AVP) in the developm ent of diabetic nephropathy and the effect of specific vasopressin V1 receptor antagonist of {1-[4-(3-acetylaminopropoxy)-benzoyl]-4-piperid yl} -3,4-dihydro-2(1H)-quinolinone (CAS 131631-89-5, OPC-21268) on alb uminuria in patients with non-insulin dependent diabetes mellitus. Bas al levels of AVP in diabetic patients showing microalbuminuria were si gnificantly high compared to diabetics without any complications, sugg esting that in those patients abnormally high amounts of AVP seem to b e secreted. Three-week treatment with OPC-21268 demonstrated that albu minuria significantly decreased without affecting renal function. Incr eased secretion of AVP may induce proliferation of renal mesangial cel ls and modify blood flows in the glomerular capillaries. The present d ata suggest that OPC-21268 may be useful for preventing the developmen t of diabetic nephropathy, although its long-term effects should be ex amined. In conclusion, AVP may play a crucial role in the pathophysiol ogy of diabetic nephropathy and that OPC-21268 seems to prevent furthe r progression of nephropathy in non-insulin dependent diabetes mellitu s.