Modulation defect of sodium pump evidenced in diabetic patients by a microcalorimetric study.
Sodium pump activity of intact erythrocytes in their own plasma was measured by microcalorimetry in 41 healthy subjects and 35 insulin-dependent diabetic patients. Results show that modulation of the sodium pump is altered in diabetic patients. Addition of insulin increases functioning of the Na(+)-K+ pump in controls but has no effect in diabetic patients. These subjects show a slower response of the Na(+)-K+ pump to the inhibitory effect of ouabain. Cross-incubation experiments suggest that these findings may be explained by the existence of a plasmatic factor that impairs the modulation of the sodium pump in diabetic patients.
Issautier
T
T
Laboratoire de Biophysique, Faculté de Pharmacie, Université d'Aix-Marseille II, France.
Kovacic
H
H
Gallice
P
P
Raccah
D
D
Vague
P
P
Crevat
A
A
D000328:Adult; D002151:Calorimetry; D003922:Diabetes Mellitus, Type 1 / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D008875:Middle Aged; D010042:Ouabain / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000097:blood*
D007328:Insulin; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase