2. Review Beta Oxidation

3. Protein Metabolism

4. 20 aa’s that combine in unique arrangements to form individual proteins

5. Amino Acids  Amino radical (NH 2 )  Carboxyl group (COOH)  The side chain (carbon, hydrogen, sometimes sulfur or nitrogen) is what gives it specific characteristics  10 aa’s are essential, cannot be synthesized in the body

6. All aa’s become part of the amino acid pool: three compartments  blood  liver  skeletal muscle

7. aa’s in the compartments are in equilibrium; change one, change all, blood is the communicator  if one compartment is low, can replenish from another: glucose-alanine cycle

8. aa’s brought to liver, converted to glucose (gluconeogenesis) and released in blood for delivery to working muscle

9. aa’s in muscle are converted to alanine, carried to liver, where amino radical is removed (deamination) carbon skeleton is converted to glucose

10. After 4 hours of continuous exercise, liver’s output of alanine-derived glucose accounts for 45% of total hepatic glucose

11. As intensity of exercise increases; so does alanine release from exercising muscles (7X)

12. Energy derived from glucose- alanine cycle can account for 10-15% of the total energy requirement

13. Amino acid metabolism can be divided as  disposal of the alpha-amino group (via alpha-ketogluterate to glutamate to ammonia to urea)  carbon skeletons are converted to intermediates of metabolism

14. If energy state is high: convert to acetyl-CoA and stored as fat

15. If energy state is low: catabolized to support demand (exercise) for energy

16. Alanine, via pyruvate, yields 15 ATP