title: Erythrocyte sodium-hydrogen antiport activity is not a predictor of diabetic nephropathy.
abstract: Erythrocyte sodium-hydrogen antiport activity was measured by Orlov's method in 36 healthy volunteers (18 with negative, 18 with positive family history of hypertension) and 52 subjects with type 1 insulin-dependent diabetes mellitus: 29 patients were without known diabetic complications, 23 patients with microangiopathy (10 with diabetic retinopathy, 13 with 'incipient' diabetic nephropathy). Normotensive healthy adults had similar antiport activities independently of a positive or negative family history of hypertension (6.45 +/- 2.61 vs. 5.80 +/- 3.07 mmol/l of cells per h, respectively). Sodium-hydrogen antiport resulted 8.38 +/- 3.91 mmol/l of cells per h in the 29 uncomplicated diabetic patients, significantly higher (p < 0.05) compared to healthy subjects, both without and with family hypertension. Complicated diabetics confirmed to have an exchange rate higher than healthy controls (8.18 +/- 2.50 mmol/l of cells per h, p < 0.01): patients with retinopathy showed the highest antiport activity (8.96 +/- 2.95 mmol/l of cells per h, p < 0.01), while patients with nephropathy had milder antiport overactivity (7.58 +/- 2.02 mmol/l of cells per h), not significantly different from either uncomplicated diabetics or healthy controls. Thus, an increased sodium-hydrogen exchange rate in peripheral erythrocytes does not seem to be an early indicator of diabetic nephropathy.
authors.affiliation: Istituto di Clinica Medica II, Università degli Studi di Pisa, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Matteucci
authors.forename: O
authors.initials: O
authors.lastname: Giampietro
mesh_terms: D000328:Adult; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism; D003929:Diabetic Neuropathies / Q000378:metabolism*; D004912:Erythrocytes / Q000737:chemistry*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000378:metabolism; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D011507:Proteinuria; D011522:Protons; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism*; D018709:Statistics, Nonparametric
chemical_list: D011522:Protons; D017923:Sodium-Hydrogen Exchangers