LO 3 Spring 2003

Learning Objectives 3

Arachidonic Acid Metabolism

1. Describe the sources of the precursors for prostaglandins and leukotrienes, including dietarily essential linoleic and a-linolenic acids.

2. Differentiate the biochemical actions of the anti-inflammatory glucocorticoids and nonsteroidal anti-inflammatory drugs.

3. Outline the "cyclic" pathway from arachidonic acid to the 2-series prostaglandins and thromboxane A₂ and the " linear" pathway to the 4-series of leukotrienes.

4. Delineate the clinical relevance of w3 fatty acids, thromboxane A₃ and PGI₂; describe the regulation of platelet aggregation in relation to diet, smoking and coronary heart disease.

5. List the general actions of prostaglandins and leukotrienes, emphasizing inflammatory, pain/fever, hypersensitivity, blood clotting and uterine effects.

Protein Turnover / Ammonia Metabolism

1. Distinguish between the essential and non-essential amino acids.

2. Define positive and negative nitrogen balance.

3. List the roles of proteolysis (protein degradation).

4. Describe the transaminase reactions for alanine and aspartic acid.

5. List the compounds by which nitrogen is excreted.

6. Draw the urea cycle, including enzymes.

Heme Metabolism / Jaundice

1. Draw, using names only, and including enzymes the heme synthetic pathway.

2 Define the regulation and manifestations of deficiencies (porphyria) for enzymes in the heme synthetic pathway.

3. Draw, using names only, the pathway for heme degradation (including post hepatic).

4. Define the difference between conjugated and unconjugated bilirubin.

5. Compare the differences in types of hyperbilirubinemia produced in anemia, hepatitis, biliary duct stones and newborn jaundice.

Overview of Biochemical Endocrinology

1. Define hormone and receptor and identify associated properties, both chemically and with respect to their biochemical and physiological significance.

2. Identify the lipophilic hormones that bind to intracellular receptors and the hydrophilic amine and peptide hormones that bind to the cell surface.

3. Identify the second messengers that are associated with specific hormones and specific types of receptors.

4. Describe the general mechanism of signal transduction via G-proteins.

5. Discuss the process leading to the production of IP₃ and DAG, and the general mechanism of action of these second messengers.

Vitamin A and Vision

1. Identify provitamin A / b-carotene, vitamin A / retinol, vitamin A ester / retinol palmitate, retinaldehyde / retinal and retinoic acid (all-trans and 9-cis) in terms of their positions on the pathway of vitamin A metabolism. Delineate which reactions are reversible and which are not.

2. Describe the biological function of each of the forms of vitamin A.

3. Outline the actions of noncovalent vitamin A binding proteins including: RBP, CRBP, CRABP, RAR and RXR.

4. Describe the role of vitamin A in the visual cycle, in particular the roles played by: retinal isomerase, opsin, rhodopsin, metarhodopsin, transducin, cGMP, phosphodiesterase, Na²⁺, Ca²⁺, recoverin, rhodopsin kinase, arrestin.

5. Define progressive vitamin A deficiency clinically and biochemically.

6. Discuss why excess vitamin A is toxic to skin, bones, liver and gut.

7. Classify vitamin A and its RAR with the ligands for PPAR, the thyroid hormone receptor (TR) and the vitamin D receptor (VDR).

Biochemistry of Disease

1. Define the terms health and disease.

2. Discuss the six points in analyzing disease from a biochemical standpoint.

3. Define genetic diseases and the human genome project.

4. Discuss the three strategies for the successful treatment of some genetic disease.