caa a22 4500 46912850X CHVBK 20180323133157.0 cr unu---uuuuu 170328e19920901xx s 000 0 eng 10.1007/BF00573484 doi (NATIONALLICENCE)springer-10.1007/BF00573484 Enhanced growth and Na+/H+ antiport activity response to serum in cultured fibroblasts of diabetic patients with nephropathy [Elektronische Daten] [R. Trevisan, J. Yip, L. Li, G. Viberti] To explore whether elevated red blood cell sodium-lithium countertransport in type 1 (insulin-dependent) diabetic patients with nephropathy is related to the physiological Na+/H+ antiport activity, we measured the activity of this antiport in serially passaged cultured skin fibroblasts from insulin-dependent diabetic patients with and without nephropathy and from non-diabetic controls. Na+/H+ antiport activity (measured as the rate of amiloride-sensitive Na+ influx) was significantly elevated in patients with nephropathy compared with patients without nephropathy and normal controls (13.35±3.8 vs 8.54±2.0 vs 7.33±2.3 nmol Na+/mg protein per min;P<0.006 andP<0.001 respectively). This raised activity in patients with nephropathy was due to an increasedV max for extracellular Na+.K m values were similar in the three groups. Amiloride-sensitive Na+ influx was also higher in cells under baseline conditions and after serum stimulation from patients with nephropathy. Intracellular pH values were significantly higher, both during active proliferation and after 10 min of exposure to serum, in cells from patients with nephropathy compared with patients without nephropathy and normal controls. Serum-stimulated incorporation of [3H]thymidine into DNA was greater in patients with nephropathy than in the other two groups. These data in cultured fibroblasts suggest that intrinsic abnormalities in cell function, independently of the metabolic disturbances of diabetes, are a feature of diabetic patients who develop nephropathy. Springer-Verlag, 1992 Cell proliferation nationallicence Diabetic nephropathy nationallicence Intracellular pH nationallicence Skin fibroblasts nationallicence Sodium-hydrogen exchange nationallicence Trevisan R. Division of Malattie del Ricambio, University of Padua, Italy aut Yip J. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut Li L. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut Viberti G. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut Acta Diabetologica Springer-Verlag 29/3-4(1992-09-01), 178-181 0940-5429 29:3-4<178 1992 29 592 https://doi.org/10.1007/BF00573484 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00573484 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Trevisan R. Division of Malattie del Ricambio, University of Padua, Italy aut NATIONALLICENCE 700 1- Yip J. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut NATIONALLICENCE 700 1- Li L. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut NATIONALLICENCE 700 1- Viberti G. Unit for Metabolic Medicine, United Medical and Dental Schools, Guy's Hospital, London, UK aut NATIONALLICENCE 773 0- Acta Diabetologica Springer-Verlag 29/3-4(1992-09-01), 178-181 0940-5429 29:3-4<178 1992 29 592 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer