1. BIOL 3320 Principle of Animal Physiology Instructor: Yong Zhu Textbook: Sherwood, Klandorf, Yancey “Animal Physiology” (2005) References: –Eckert Animal Physiology (2002) 5th

2. Course Introduction What is Principle of Animal Physiology –studies functions of organ systems, tissues and molecules in multicellular animals. –deals physiological functions of animals and adaptation to various physiological and environmental conditions.

3. Course Introduction What is Principle of Animal Physiology –Studies various organ systems such as nervous system, endocrine system, circulation system, respiratory system, muscle movement, osmoregulation, metabolism, growth, aging and reproduction –will be discussed from homeostatic, comparative, and adaptive aspects.

4. Course Introduction Course Objectives: –structures and functions of vertebrate organ systems –physiological processes and molecular mechanisms –regulation, adaptation, signaling pathways etc

5. Course Introduction Evaluation: 5 Test periods, 100 points for each test periods (exam 70, quiz 10, attendance 20), attendance 20) Final exam300 points Total points 800 points

6. Course Introduction Keys to success –Come to Class –Keep up with the readings –talk to the professor If you find you are having difficulty with the materials, DO NOT WAIT until you have problems with an exam before coming in for help Contact –email: zhuy@ecu.edu –tel: 328-6504 office hour: –Tuesday/Thursday 2-3 PM or By appointment

7. Fig. 1-11, p.18

8. Why study animal physiology? Scientific curiosity Commercial and agricultural application Insights into human physiology

9. Function depends on structure

10. Adaptation Evolution through natural selection leading to an organism whose physiology, anatomy and behavior are matched to demands of its environment. Adaptation typically occurs in a gradual manner over many generations Acclimatization Physiological, biochemical, or anatomic change within an individual animal during its life that results form that animal’s chronic exposure in its native habitat to new, natural occurring environmental conditions. Acclimation Refers to the same process as acclimatization when changes are induced experimentally in the laboratory or in the wild by an investigator

11. Homeostasis: the tendency of organisms to regulate and maintain relative internal stability

13. Fall in body temperature below set point Temperature-monitoring nerve cells Temperature control center Skeletal muscles (and other effectors) Heat production through shivering and other means Fall in body temperature below set point Set Point *Relieves (negative feedback) Fig. 1-8c, p.13

14. Uterus begins contractions Stretch sensors Mother’s hypothalamus Pituitary gland Contractions enhanced (c) Example of positive feedback: birth of a mammal Oxytocin secreted Signal from mature fetus Fig. 1-10c, p.17

15. Feedback: The return of output to the input part of a system. In negative feedback, the sign of the output is inverted before it is fed back to the input so as to stabilize the output. In positive feed back, the output is unstable because it is returned to the input without siganl inversion, and thus becomes self-reinforcing, or regenerative.

17. August Krogh principle: Choose appropriate animal to study a defined physiological system.

18. Methods in physiology research  Physiological problems can be approached by physiological, pharmacological, biochemical, cellular and molecular techniques  Frequently asked questions  Where is the signaling molecules produced?  What is the structure of the molecule?  How is the process controlled?  What are the physiological roles?  What are the mechanisms of action? Physiological Methodology

19. Physiology Methodology Where is the signaling molecules produced?  Surgical methods: removal and replacement  Use antibodies to locate the molecules involved in physiological process  Use nucleotide probes to locate the mRNA for the molecules involved in physiological process

20. Physiology Methodology

21. immunohistofluorescence

22. Physiology Methodology In situ hybridization

23. Physiology Methodology What is the structure of the molecules? –Is it a peptide?--digest with a protease –is it extractable in organic solvents?— steroids and eicosanoids –Purification –cDNA cloning (peptide molecules)

24. Physiology Methodology

26. How is process controlled? –Regulators to be tested » in vivo: whole animal experiment »in vitro: cell and tissue culture –measurement: »RIA »ELISA Physiology Methodology

27. Radioimmunoassay (RIA) –principles: high-affinity, high-titer anti-hormone antibodies are able to bind radioisotope-labeled hormone in a reversible manner and such binding is competitively inhibited by unlabeled hormone –highly sensitive: detect hormones in minute concentration –highly specific: do not cross-react with other hormones Physiology Methodology

29. A Sandwich ELISA (1) Plate is coated with a capture antibody; (2) sample is added, and any antigen present binds to capture antibody; (3) detecting antibody is added, and binds to antigen; (4) enzyme-linked secondary antibody is added, and binds to detecting antibody; (5) substrate is added, and is converted by enzyme to detectable form. Physiology Methodology

30. What are the physiological roles  Removal and replacement therapy remove the organ and observe consequences  In vivo and in vitro approaches  Immunoneutralization use antibody to abolish endogenous molecules action Physiology Methodology

31.  Pharmacological studies use agonists and antagonists  Molecular and genetic techniques  Knockdown approaches: decrease the production of molecule  gene knockout: deleting the gene encoding a hormone or its receptor  overexpression: increasing the amount of hormone production Physiology Methodology

32. What are the mechanisms of action? Receptor radioreceptor assay: binding characteristics receptor cloning: primary structure gene knockout and knockdown: function Physiology Methodology

33.  Second messengers and downstream signals  enzyme assay: phosphorylation  electrophysiological methods: ion movement  pharmacological studies: Physiology Methodology

34. Why do we clone proteins and receptors –provide structural information, can be used to synthesize small peptides –production of hormones by recombinant DNA techniques Physiology Methodology

35. –Transgenic studies Physiology Methodology

36. Common Vertebrate models used in physiological research –Bony fish: largest and most diverse group; some unique features; great models to study neuroendocrine regulation and early development –Amphibians: good model to study hormones in early development –Birds: chicken are common models –Mammals: focus of endocrine research; e.g. mouse, rat Physiology Methodology