Effect of porcine gastric inhibitory polypeptide on beta-cell function in type I and type II diabetes mellitus.
The effect of highly purified natural porcine GIP on C-peptide release was examined in six type I (insulin-dependent) diabetics (IDD) with residual beta-cell function, six type II non-insulin-dependent) diabetics (NIDD), and six normal subjects. All subjects were normal weight. From -120 minutes to 180 minutes glucose or insulin was infused IV to achieve a constant plasma glucose level of 8 mmol/L. On two separate days GIP (2 pmol/kg/min) or isotonic NaCl at random were infused from 0 to 30 minutes. After 10 minutes of GIP infusion plasma IR-GIP concentrations were in the physiologic postprandial range. At 30 minutes a further increase in IR-GIP to supraphysiologic levels occurred. In all subjects plasma, C-peptide increased more after 10 minutes of GIP infusion (IDD, 0.48 +/- 0.05; NIDD, 0.79 +/- 0.11; normal subjects, 2.27 +/- 0.29 nmol/L) than on the corresponding day with NaCl infusion (IDD, 0.35 +/- 0.03; NIDD, 0.62 +/- 0.08; normal subjects, 1.22 +/- 0.13 nmol/L, P less than .05 for all). The responses of the diabetics were significantly lower than that of the normal subjects (P less than .001 for both groups). No further increase in C-peptide occurred during the remaining 20 minutes of the GIP infusion in the diabetic subjects (IDD, 0.49 +/- 0.05; NIDD, 0.83 +/- 0.10 nmol/L). In the presence of a plasma glucose concentration of 8 mmol/L, physiologic concentrations of porcine GIP caused an immediate but impaired beta-cell response in IDD and NIDD patients.
Krarup
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Saurbrey
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Moody
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AJ
Kühl
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Madsbad
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D000328:Adult; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000097:blood / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000097:blood; D007515:Islets of Langerhans / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D013552:Swine
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide