Increased kidney and liver insulin-like growth factor II/mannose-6-phosphate receptor concentration in experimental diabetes in rats.
Diabetic renal hypertrophy is preceded by a transient increase in kidney insulin-like growth factor I and insulin-like growth factor binding protein concentration suggesting a renotropic function in diabetic kidney growth. In order to further examine the possible involvement of the insulin-like growth factor system in initial diabetic kidney growth, we have studied the expression of the kidney insulin-like growth factor II/mannose-6-phosphate receptor during the first 4 days after induction of diabetes in rats. Using a specific antiserum (#3637) raised against the insulin-like growth factor II/mannose-6-phosphate receptor of rat chondrosarcoma a specific band with an apparent molecular weight of 220 kDa was identified in Western blotting experiments with kidney and liver protein extracts. In untreated diabetic rats a transient increase of the kidney and liver insulin-like growth factor II/mannose-6-phosphate receptor concentration was measured 24-48 h after the induction of diabetes (mean increase in kidney 140% and liver 112%, n = 5). This increase was followed by a subsequent decrease in the insulin-like growth factor II/mannose-6-phosphate receptor protein concentration after 3-4 days of diabetes. Insulin treatment prevented the rise both in kidney and liver tissue. Kidney weight in untreated diabetic rats increased by 25% after 4 days. In conclusion, the present study shows a transient increase of insulin-like growth factor II/mannose-6-phosphate receptor concentration in hypertrophying diabetic kidneys and in diabetic livers, contemporarily with the previously described increase in kidney insulin-like growth factor I and insulin-like growth factor binding protein content.(ABSTRACT TRUNCATED AT 250 WORDS)
Flyvbjerg
A
A
Institute of Experimental Clinical Research, Aarhus Kommunehospital, Denmark.
Kessler
U
U
Kiess
W
W
D000818:Animals; D001345:Autoradiography; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D015151:Immunoblotting; D007328:Insulin / Q000097:blood; D007668:Kidney / Q000378:metabolism*; D008024:Ligands; D008099:Liver / Q000378:metabolism*; D008297:Male; D009929:Organ Size; D051381:Rats; D017208:Rats, Wistar; D017527:Receptor, IGF Type 2 / Q000378:metabolism*
D001786:Blood Glucose; D007328:Insulin; D008024:Ligands; D017527:Receptor, IGF Type 2