Assessment of islet beta-cell mass in isolated rat pancreases perfused with D-[(3)H]mannoheptulose.
D-mannoheptulose is apparently transported into cells mainly at the intervention of GLUT-2 and hence was recently proposed as a tool to label preferentially insulin-producing beta-cells in the pancreatic gland. The validity of such a proposal was investigated in the present study conducted in isolated perfused pancreatic glands from control and streptozotocin-induced diabetic rats. After a 30-min equilibration period, D-[(3)H]mannoheptulose (0.1 mM) and [U-(14)C]sucrose (0.5 mM) were infused for 15 min in the presence of 30 mM D-glucose. The pancreatic glands were then perfused for 10 min with a nonradioactive medium during and after administration of cytochalasin B (0.02 mM). Under these experimental conditions, the intracellular distribution space of D-[(3)H]mannoheptulose averaged 5.42 +/- 0.75 nl/mg in control animals, whereas it failed to be significantly different from zero in the streptozotocin rats. The present procedure may thus allow the assessment of the relative contribution of islet beta-cells to the total mass of the pancreatic gland.
Ladrière
L
L
Laboratory of Experimental Medicine, Brussels Free University, B-1070 Brussels, Belgium.
Leclercq-Meyer
V
V
Malaisse
W J
WJ
D000818:Animals; D002250:Carbon Radioisotopes; D002452:Cell Count; D003571:Cytochalasin B / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000378:metabolism*; D004195:Disease Models, Animal; D005947:Glucose / Q000008:administration & dosage; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007424:Intracellular Fluid / Q000378:metabolism; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008356:Mannoheptulose / Q000008:administration & dosage / Q000493:pharmacokinetics*; D009929:Organ Size / Q000502:physiology; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism*; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D013311:Streptozocin; D013395:Sucrose / Q000008:administration & dosage / Q000493:pharmacokinetics; D014316:Tritium
D002250:Carbon Radioisotopes; D007328:Insulin; D014316:Tritium; D003571:Cytochalasin B; D013395:Sucrose; D013311:Streptozocin; D008356:Mannoheptulose; D005947:Glucose