Degranulation effect of ferric nitrilotriacetate (Fe3+-NTA) on the pancreatic islet beta-cells: its acute toxic effect on glucose metabolism.
A single injection of ferric nitrilotriacetate (Fe3+-NTA) caused a transitory increase in plasma immunoreactive insulin (IRI) and plasma immunoreactive glucagon (IRG) in rats. They reached maximum levels at 2 days after injection and returned to the normal range at 10 days. At 2 days after Fe3+-NTA injection, blood glucose level was normal but the glucose tolerance test (GTT) was impaired. There was a further increase in plasma IRI level and IRG level was suppressed after glucose loading. At 10 days after Fe3+-NTA injection, glucose tolerance was normal and IRI also returned to the normal range. No degenerative changes were found on H.E.-stained rat pancreatic tissue sections after Fe3+-NTA injection. Histochemical staining, however, showed a reduction in beta-granules and heavy metals (Timm's granules) from islet cells in the central area of the rat pancreatic islet 1 to 3 days after injection of Fe3+-NTA. The fading remained in some islets even at 10 days after injection, but by then the beta-granule distribution was restored in most islet cells. The results indicate a single Fe3+-NTA injection induced transitory instability of the pancreatic islet beta-cell granules and the glucose intolerance with a hyperresponse of IRI.
D000818:Animals; D003594:Cytoplasmic Granules / Q000187:drug effects; D005290:Ferric Compounds / Q000494:pharmacology* / Q000633:toxicity; D005934:Glucagon / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006943:Hyperglycemia / Q000139:chemically induced; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007501:Iron / Q000494:pharmacology*; D007515:Islets of Langerhans / Q000187:drug effects*; D008297:Male; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives*; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains
D005290:Ferric Compounds; D007328:Insulin; D005934:Glucagon; D007501:Iron; D005947:Glucose; D009571:Nitrilotriacetic Acid; C020326:ferric nitrilotriacetate