Insulin-like growth factor-I in non-insulin-dependent diabetic monkeys: basal plasma concentrations and metabolic effects of exogenously administered biosynthetic hormone.
Plasma insulin-like growth factor-I (IGF-I) concentrations and the effects of exogenous IGF-I administration were determined in 26 rhesus monkeys; each animal was well characterized regarding its degree of obesity, plasma glucose and insulin levels, and glucose tolerance (KG). Five separate groups were identified: lean normal, obese normoinsulinemic and normoglycemic, obese hyperinsulinemic with normal glucose tolerance, impaired glucose tolerant, and spontaneously diabetic (type II, non-insulin-dependent diabetes mellitus [NIDDM]). Basal plasma IGF-I levels in all monkeys ranged from 249 to 1,093 ng/mL and were strongly associated with age (r = -.66; P less than .001) and KG (r = .59; P less than .001), but not with body weight, body fat, or fasting plasma glucose or insulin levels. In addition, the acute insulin-like effects of exogenously administered IGF-I on glucose disappearance were studied in vivo in a dose-response comparison to insulin (subcutaneous administration of IGF-I at doses of 50, 100, or 200 micrograms/kg v insulin at 0.3 U/kg). Five hyperinsulinemic normoglycemic monkeys (fasting plasma glucose, 67 +/- 2 mg/dL; insulin, 163 +/- 42 microU/mL) and overt type II diabetic monkeys (fasting plasma glucose, 201 +/- 13 mg/dL; insulin, 38 +/- 6 microU/mL) each underwent a series of three to five experiments to determine the time course and degree of hypoglycemia induced by IGF-I as compared with insulin or with control (saline) injection.(ABSTRACT TRUNCATED AT 250 WORDS)
Obesity and Metabolism Laboratory, University of Maryland, School of Medicine, Baltimore 21201.
N L
NL
Bodkin
R
R
Sportsman
R D
RD
DiMarchi
B C
BC
Hansen
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D003920:Diabetes Mellitus / Q000097:blood / Q000235:genetics / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000235:genetics / Q000503:physiopathology; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000494:pharmacology; D008253:Macaca mulatta; D009765:Obesity / Q000097:blood / Q000235:genetics / Q000503:physiopathology; D009994:Osmolar Concentration
D001786:Blood Glucose; D007328:Insulin; D007334:Insulin-Like Growth Factor I