Date of Award

1-1-2009

Document Type

Masters Thesis

Degree Name

M.S.

Organizational Unit

Biological Sciences

First Advisor

Joseph Angleson, Ph.D.

Second Advisor

Nancy Lorenzon

Third Advisor

Robert M. Dores

Keywords

Alpha cells, cAMP, Cyclic AMP, Endocrinology, Epac, PKA, Protein kinase A

Abstract

Blood glucose levels are regulated by the interactions between insulin and glucagon. Pancreatic alpha cells release glucagon in response to a drop in blood sugar. Pancreatic alpha cells appear to be regulated through multiple signaling pathways. One potential method of regulation occurs from α-MSH or epinephrine stimulated production of the intracellular messenger cyclic AMP. Exocytosis of dense core vesicles containing glucagon ultimately requires an increase in cytosolic calcium. This study focused on the link between cyclic AMP and calcium in pancreatic alpha cells which allows alpha cell regulation. Interactions between calcium and cyclic AMP in pancreatic alpha cells consists of PKA-dependant and PKA-independent pathways. The results indicate cyclic AMP pathways control L-type voltage-gated calcium channels and also increase cytoplasmic calcium from intracellular stores. Store release appears to be through IP3 mediated pathways and not through the ryanodine-sensitive receptor.

Publication Statement

Copyright is held by the author. User is responsible for all copyright compliance.

Rights Holder

Julianne Michelle Imseis

Provenance

Received from ProQuest

File Format

application/pdf

Language

en

File Size

65 p.

Discipline

Cellular biology, Molecular biology



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