1. GLUCAGON Presented By Daniel Vakili

2. Familiar Analogy

3. Glucagon Glucagon Receptor Target Tissue with stored glucose Glucose

4. Structure >29 amino acid polypeptide hormone >nonsteroid

5. Where does it come from? >Synthesized and secreted from alpha cells in the islets of langerhans in the pancreas. > Cleaved from proglucagon

7. Action >Raise Blood Sugar - Glycogenolysis - Gluconeogenesis >Target tissues - Liver, Muscle, Fat >Glucagon and Insulin are part of a feedback system that keep blood sugar at normal levels

8. Receptor G-Protein Coupled Receptor > Part of the GPCR Family >Heptahelical > Extracellular region binds to ligands > Intracellular region interacts with multi-subunit G- Protein

9. Receptor > Ligand activates > GDP-GTP > alpha subunit dissociates

10. cAMP: a secondary messenger cyclic adenosine monophosphate Glucagon-Receptor > G-proteins dissociate > α subunit-adenylate cyclase > cAMP > removes inhibitory subunit of PKA

12. Normal Blood Values Insulin and Glucagon normally keep plasma glucose >below 170mg/dl after a meal (absorptive state) >above 50mg/dl between meals(postabsorptive state)

13. Too Little Glucagon: Hypoglycemia > Symptoms: tremor, hunger, weakness, weakness, blurred vision, and mental confusion.

14. Too Much Glucagon: >Glucagonoma- tumor of alpha cells resulting in overproduction > Hyperglycemia > Ketoacidosis - fatty acids to Ketone bodies > Gluconeogenesis - Weight loss, anemia, ketoacidosis, diabetes mellitus.

15. Conclusion Glucagon is a hormone antagonist to insulin, signaling the release of glucose from storage into the blood through glycogenolysis and gluconeogenesis. Important for maintaining homeostasis.