Item – Theses Canada

​
OCLC number
1019487335
Link(s) to full text
LAC copy
Author
Bansal, Pritpal Singh.
Title
Insulin-induced Suppression of A-type GABA Receptor Signaling in the INS-1 Pancreatic beta-cell Line.
Degree
M. Sc. -- University of Toronto, 2010
Publisher
Ottawa : Library and Archives Canada = Bibliothèque et Archives Canada, 2011.
Description
1 online resource
Notes
Includes bibliographical references.
Abstract
<?Pub Inc> GABA and GABA type A receptor (GABAAR) are expressed in pancreatic [beta]-cells and comprise an autocrine signaling system. How the GABA-GABAAR system is regulated is unknown. In this study, I investigated insulin's effect on this system in the INS-1 [beta]-cell line. I found that GABA evoked current (IGABA) in INS-1 cells, resulting in membrane depolarization. Perforated-patch recordings showed that pre-treatment of insulin or zinc-free insulin suppressed IGABA in INS-1 cells (p < 0.01). Radioimmunossay showed that GABA (30 [mu]M) increased C-peptide secretion from INS-1 cells, which was blocked by GABAAR antagonist picrotoxin, indicating that GABA increased insulin secretion through activation of GABAAR. However, insulin significantly reduced the stimulatory effect of GABA on C-peptide secretion (p < 0.05). These data suggest that GABA released from [beta]-cells positively regulates insulin secretion via GABAAR activation, and that insulin negatively regulates the [beta]-cell secretory pathway likely via inhibiting the GABA-GABA AR system in [beta]-cells.
ISBN
9780494725092
0494725095