ENDOTHELINS URINARY-EXCRETION IS INCREASED IN SPONTANEOUSLY DIABETIC RATS - BB BB/

Previously we reported (1) an increase of endothelin-1,2 (ET) content, in urine of rats made diabetic with streptozotocin (STZ), starting th ree days and up to 20 weeks from diabetes induction. The increased ET excretion was considered as an early marker of endothelial damage. To ascertain if this phenomenon was present also in a strain of spontaneo usly diabetic rats, endothelin-1,2 urinary excretion was determined in BB/BB diabetic rats, and their control (BB/WB), at different times af ter the onset of diabetes, (two, four, six and twelve weeks). BB/BB di abetic rats showed elevated urinary excretion of endothelins as compar ed to BB/WB control rats, starting two weeks after diabetes onset, and up to twelve weeks. In the same animals, Nerve Conduction Velocity (N CV), was monitored at the same time as an index of the occurrence of a diabetes complication (peripheral neuropathy). NCV resulted to be imp aired in the BB/BB diabetic rats as compared to control rats; however the increase of ET in urine, is earlier in comparison to peripheral ne uropathy. These data suggest the hypothesis that endothelial damages p receed the overt manifestations of peripheral neuropathy associated to diabetes.