Plasma levels of adrenomedullin, a vasoactive peptide, in type 2 diabetic patients with and without retinopathy

Department of Clinical Sciences, University of Rome La Sapienza, Rome, Italy.
Minerva endocrinologica (Impact Factor: 1.46). 06/2007; 32(2):73-8.
Source: PubMed


The aim of this study was to investigate whether adrenomedullin (AM) secretion is modified in type 2 diabetic patients with and without retinopathy.
The study was performed on 92 patients with type 2 diabetes, 65 of whom had uncomplicated diabetes, 27 had retinopathy, and 40 had mild to moderate hypertension. Patients with serum creatinine levels >1.2 mg/dL, were excluded. Circulating AM was assayed using a specific radioimmunoassay.
AM concentrations were significantly higher in type 2 diabetic patients (25+/-2.1 pg/mL) than in the 31 normal subjects (11+/-0.8 pg/mL) (P<0.001). Type 2 diabetic patients with retinopathy had significantly greater AM levels (30.8+/-3.4 pg/mL) than both controls (P<0.001) and type 2 diabetic patients without retinopathy (25.2+/-2 pg/mL same as previous value) (P<0.001). No statistical difference was found between diabetic patients with pre-proliferative retinopathy (27.3+/-4.7 pg/mL) and proliferative retinopathy (24+/-3.1 pg/mL) (P=0.543). In type 2 diabetic patients, a significant correlation between plasma AM levels and HbA1c values (r=0.467; P<0.01) was found.
Our findings indicate that circulating AM is increased in type 2 diabetic patients and that increase correlates with poor glucose metabolic control and presence of retinopathy.

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Available from: Enzo Maria Vingolo
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