Date of Award

1-1-2017

Document Type

Thesis

Degree Name

M.S.

Department

Biological Sciences

First Advisor

Robert M. Dores, Ph.D.

Keywords

Biophysics

Abstract

The endocrine pancreas is responsible for maintaining glycemic equilibrium in the body. Given the importance of this blood-glucose homeostasis and the implication an unbalance has on Diabetes mellitus, the study of the glucose-sensing alpha and beta cells in the pancreas is a popular field for scientific researchers. In this study, we use immunofluorescence, qPCR analysis, intracellular calcium experiments, and biochemical glucagon secretion assays to determine if the commercially available tumor cell line clone, α-TC1-6 obtained from American Type Culture Collection, is an appropriate model system for glucagon secretion in pancreatic alpha cells. We confirm the production of the hormone peptide glucagon as well as increased intracellular calcium activity associated with a decrease in extracellular glucose. However, the resultant stimulated secretion of glucagon at low glucose levels is much less than expected from an endocrine cell and indicates deficiency of the pathway. The American Type Culture Collection α-TC1-6 cell line also retains the activity of the KATP channel and an agatoxin-sensitive P/Q-type calcium channel, but does not exhibit activity of a TTX-sensitive sodium channel and lacks the expression of the receptor of a key paracrine regulator, epinephrine. Paracrine control via an increase in cytosolic cAMP is observed but not coupled with glucagon secretion. Due to these shortcomings, the ATCC α-TC1-6 cell line is not a good model system for the study of regulated glucagon secretion in pancreatic alpha cells.

Copyright Statement / License for Reuse

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Provenance

Received from ProQuest

Rights holder

Larissa M Ikenouye

File size

52 p.

File format

application/pdf

Language

en

Discipline

Biophysics

Share

COinS