Pulsatile insulin release from islets isolated from three subjects with type 2 diabetes
| Autor: | Ramon Gomis, Jian-Man Lin, Marta E Fabregat, Peter Bergsten |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Blood Glucose
Male medicine.medical_specialty Pulsatile insulin Endocrinology Diabetes and Metabolism medicine.medical_treatment Type 2 diabetes In Vitro Techniques Body Mass Index chemistry.chemical_compound Islets of Langerhans Insulin resistance Tolbutamide Reference Values Internal medicine Insulin Secretion Internal Medicine medicine Homeostasis Humans Insulin Age of Onset Cells Cultured Aged Chemistry Middle Aged medicine.disease Insulin oscillation Perfusion Kinetics Endocrinology Glucose L-Glucose Diabetes Mellitus Type 2 medicine.drug Hormone |
| Zdroj: | Diabetes. 51(4) |
| ISSN: | 0012-1797 |
| Popis: | Plasma insulin in healthy subjects shows regular oscillations, which are important for the hypoglycemic action of the hormone. In individuals with type 2 diabetes, these regular variations are altered, which has been implicated in the development of insulin resistance and hyperglycemia. The origin of the change is unknown, but derangement of the islet secretory pattern has been suggested as a contributing cause. In the present study, we show the dynamics of insulin release from individually perifused islets isolated from three subjects with type 2 diabetes. Insulin release at 3 mmol/l glucose was 10.5 ± 4.5 pmol · g−1 · s−1 and pulsatile (0.26 ± 0.05 min−1). In islets from one subject, 11 mmol/l glucose transiently increased insulin release by augmentation of the insulin pulses without affecting the frequency. Addition of 1 mmol/l tolbutamide did not increase insulin release. In islets from the remaining subjects, insulin release was not affected by 11 mmol/l glucose. Tolbutamide transiently increased insulin release in islets from one subject. Insulin release from four normal subjects at 3 mmol/l glucose was 4.3 ± 0.8 pmol · g−1 · s−1 and pulsatile (0.23 ± 0.03 min−1). At 11 mmol/l glucose, insulin release increased in islets from all subjects. Tolbutamide further increased insulin release in islets from two subjects. It is concluded that islets from the three individuals with type 2 diabetes release insulin in pulses. The impaired secretory response to glucose may be related to impaired metabolism before mitochondrial degradation of the sugar. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|