Effect of octreotide on experimental diabetic renal and glomerular growth: importance of early intervention.
IGF-I acts as a renotropic factor in early streptozotocin-induced diabetes. Somatostatin analogue (octreotide) treatment initiated at the onset of diabetes prevents kidney IGF-I accumulation and renal growth. Seven days of octreotide treatment initiated after 3, 5, 7 or 9 days of untreated diabetes was investigated. Diabetic renal hypertrophy was followed by renal hyperplasia. Compared with placebo-treated diabetic rats, the earliest octreotide intervention was followed by a greater reduction in renal growth compared with intervention later on (days 3 to 10, 12%; days 5 to 12, 10%; days 7 to 14, 9%; days 9 to 16, 6%; P < 0.05). Octreotide treatment was unable to reduce protein accumulation and kidney DNA increase consistently. No difference in glomerular volume fraction or total glomerular volume was observed between placebo- and octreotide-treated diabetic rats. Octreotide treatment was followed by reduced kidney and serum IGF-I especially following early intervention, while no effect over that of diabetes was observed in the later intervention periods. The results confirm the notion that initial renal IGF-I accumulation is a prerequisite for early diabetic kidney hypertrophy in rats and show that delayed octreotide treatment cannot reverse renal and glomerular growth which is already manifest.
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D003928:Diabetic Nephropathies / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D006965:Hyperplasia; D006984:Hypertrophy / Q000139:chemically induced; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D007678:Kidney Glomerulus / Q000187:drug effects / Q000473:pathology; D008297:Male; D015282:Octreotide / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D007334:Insulin-Like Growth Factor I; D015282:Octreotide