EFFECT OF GH IGF-I DEFICIENCY ON LONG-TERM RENAL CHANGES AND URINARY ALBUMIN EXCRETION IN DIABETIC DWARF RATS/

Growth hormone (GH) and insulin-like growth factor I (IGF-I) may play a role in early diabetic renal and glomerular growth and in the later development of experimental diabetic kidney disease. Rats from a genet ic GH/IGF-I-deficient dwarf rat strain were made streptozotocin diabet ic and were compared with nondiabetic dwarf rats. GH/IGF-I-intact rats with and without diabetes served as controls. After 6 mo of diabetes, kidney weight and total glomerular volume increased significantly in GH/IGF-I-intact diabetic rats compared with the nondiabetic GH/IGF-I-i ntact rats (P < 0.05), whereas the diabetic dwarf rats had insignifica nt changes compared with dwarf control rats. By the end of the study, urinary albumin excretion (UAE) increased from similar base levels of similar to 15-20 mu g/24 h to 473 +/- 52 (SE) mu g/24 h in GH/IGF-I-in tact diabetic rats compared with 151 +/- 32 mu g/24 h in diabetic dwar f rats (P < 0.01). In conclusion, isolated GH/IGF-I deficiency reduces the degree of renal and glomerular hypertrophy and the increase in UA E after 6 mo of experimental diabetes in GH/IGF-I-deficient rats.