The influence of glimepiride on the binding kinetics of insulin with its skeletal muscle and liver receptors in rats with short term and prolonged hyperglycemia induced by streptozotocin.

Background: The aim of the study was to determine the influence of glimepiride on the binding kinetics of insulin with its skeletal muscle receptor in rats with transient and prolonged hyperglycemia induced by streptozotocin.

Material/methods: The studies were performed on healthy male Wistar rats with a body mass of 220+/-30 g, fed with LSM-type standard chow, and given water ad libitum. Transient or prolonged hyperglycemia was induced by intraperitoneal administration of streptozotocin. Blood samples were taken from the right heart ventricle to heparinized test tubes and centrifuged for 10 minutes at 700 i. g. Plasma was collected and the glucose level was determined. From each animal 1 g of skeletal muscle and 1 g of liver were collected as well, placed in liquid nitrogen and stored until determination of the affinity and number of receptors.

Results: We found an increase in affinity and binding capacity of high- and low-affinity receptors in rats with both transient and prolonged streptozotocin-induced hyperglycemia. The affinity and binding capacity of receptors increased under the influence of glimepiride in transient hyperglycemia caused by streptozotocin administration.

Conclusions: The affinity and binding capacity of receptors increased under the influence of glimepiride in the course of transient hyperglycemia. The lack of changes in the specific insulin binding and binding capacity of receptors of both low and high affinity in the group of animals with prolonged hyperglycemia requires explanation.