Kidney IGF-I and renal hypertrophy in GH-deficient diabetic dwarf rats.
Insulin-like growth factor I (IGF-I) has been proposed as a renotropic factor in initial diabetic kidney growth. To examine the effects of an isolated growth hormone (GH) and IGF-I deficiency on diabetic renal hypertrophy, dwarf rats were made diabetic and studied over a period of 7 days. Diabetic dwarf rats treated with human GH (hGH) or insulin and diabetic rats with intact pituitary were used as controls. In diabetic control animals kidney weight had increased by day 2 (P less than 0.01), and the increase amounted to 27% after 7 days, whereas untreated diabetic dwarf rats had a slower and lesser degree of kidney weight increase, reaching significance on day 7 only, amounting to 8%. hGH administration in diabetic dwarf rats increased the kidney weight on day 7 when compared with untreated diabetic dwarf rats (P less than 0.05) and was 19% over that of insulin-treated diabetic dwarf rats. The glomerular volume had increased by 43% in untreated diabetic control rats at day 7, compared with a 29% increase in untreated diabetic dwarf rats (P less than 0.05). hGH administration in diabetic dwarf rats increased the glomerular volume by 46%, comparable to the increase seen in diabetic control animals. Kidney IGF-I was increased on day 2 by 51 and 46% in saline- and hGH-injected diabetic dwarf rats, respectively, but a significantly higher increase in kidney IGF-I amounting to 96% was seen in diabetic control rats.(ABSTRACT TRUNCATED AT 250 WORDS)
Flyvbjerg
A
A
Institute of Experimental Clinical Research, University of Aarhus, Aarhus Kommunehospital, Denmark.
Frystyk
J
J
Osterby
R
R
Orskov
H
H
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D004392:Dwarfism / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D013006:Growth Hormone / Q000172:deficiency* / Q000494:pharmacology; D006579:Heterozygote; D006984:Hypertrophy; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D007678:Kidney Glomerulus / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011922:Rats, Mutant Strains
D007328:Insulin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone