Avtor/Urednik     Chowdhury-Haque, Helena
Naslov     Vpliv inzulina na dinamiko sprememb površine membrane adipocita podgane v kulturi
Tip     monografija
Kraj izdaje     Ljubljana
Založnik     Medicinska fakulteta
Leto izdaje     2002
Obseg     str. 51
Jezik     slo
Abstrakt     In the last decade it has become clear that adipocytes secrete many different products, which have important physiological role, hence fat tissue is considered as a major endocrine organ in the body. In addition adipocytes are important target cells for hormone action, especially insulin. The aim of our research was to understand the molecular mechanisms of insulin action in single adipocytes. It is well established that insulin induces the translocation of glucose transporter isoform 4 (GLUT4) to the plasma membrane of adipocytes. This in turns triggers an increased permeability of the adipocyte plasma membrane to glucose. The exact mechanism of stimulation of this process is not known, but it is very likely that the exocytosis of the GLUT4 vesicles is involved in the last step of these events. Exocytosis is the universal process of eucarionic cells where the vesicle membrane fuses with the plasma membrane. This event is inseparably bound to the increase of the plasma membrane area. Therefore, if GLUT4 translocation includes exocytosis, one should be able to detect an insulin-induced increase in the surface area of the plasma membrane in a single adipocyte. In this study we wanted to establish whether the resulting effect of insulin-induced signaling pathway is regulated exocytosis of membrane vesicles. To study this process on the single cell, we isolated and cultured rat adipocytes in primary culture. We used electrophysiological method *patch-clamp* to measure membrane capacitance (Cm). Cm is linearly correlated to the membrane surface area, which is changing due to exocytosis and endocytosis. We showed that ATP application resulted in an increase of the Cm, however increase in Cm, after insulin addition was not significantly different from control cells. (Abstract truncated at 2000 characters).
Deskriptorji     ADIPOCYTES
INSULIN
EXOCYTOSIS
ELECTRIC CONDUCTIVITY
BIOLOGICAL TRANSPORT, ACTIVE
RATS
FLUORESCENT DYES
GLUCOSE
CELLS, CULTURED