Hormones ,it's types and how they workqpptx

Human physiology
What is hormones
How they work

1. SEMESTER V Course Title: Human Physiology Course code: BCH-330 Credit Hours: 3(3-0)   Aims and Objectives: This course is designed to provide a holistic overview of the various aspects of human physiology   THEORY: Gastrointestinal tract GIT and digestive system, Liver, Pancreas and gal bladder. Respiration: Structure and functions of lungs; transport of oxygen and carbon dioxide in blood and acid base balance. Specialized Tissues: Structure and functions of muscle. Kidney; structure and functions, acid base balance, water and electrolyte balance. Brain and spinal cord: different compartments of brain and functions of sp i nal cord, general physiology of eyes cones and rod cells and their role in vision, range of human vision. Ear: general physiology of ear, Mechanism of hearing, role in balance of body. Connective tissue composition and their functions. Structure of Bones, Skin, Hair and Nail

2. Introduction to hormones

3. Endocrine system interacts with the nervous system to coordinate and integrate body activities by means of hormones . Hormones are small molecules or proteins, produced by endocrine tissue or organ, released into the circulation, and carried to other tissues, where they act through receptors to bring about changes in cellular activities. Hormones can also be classified by the way they get from their point of release to their target tissue Paracrine a type of cellular communication in which a cell produces a signal to induce changes in nearby cells Autocrine is a form of  cell signaling in which a cell secretes a hormone or chemical messenger (called the autocrine agent) that binds to autocrine receptors on that same cell Exocrine tissues , such as salivary glands, and sebaceous glands, secrete chemical substances through ducts into an open space.

4. Major Functions of Hormones a) Regulate metabolic processes (e.g. thyroid hormones). b) Control the rate of chemical reactions (e.g. growth hormone). c) Aid in the transport of substances across the cell membrane of target cells (e.g. insulin and glucagon). d) Regulate water and electrolyte balances (e.g. antidiurectic hormone, calcitonin, and aldosterone). e) Play a vital role in reproduction, growth and development (e.g. estrogens , progesterone, and testosterone).

5. Major Endocrine Organs

6. Hormone Release Is Regulated by Neuronal and Hormonal Signals CNS receive all massages Hypothalamus produce regulatory hormones That goes to Pituitary gland Pituitary gland have two parts Posterior Pituitary (short peptide hormones oxytocin and vasopressin)

7. Anterior Pituitary ( Long poly peptides) responds to hypothalamic hormones carried in the blood, producing tropic hormones , or tropins endocrine glands, which includes the adrenal cortex, thyroid gland, ovaries, and testes corticotropin -releasing hormone

8. Hormone Release Is Regulated by Neuronal and Hormonal Signals

9. Major Endocrine Hormones

10. Hormones action Most hormones adhere to the following action plan: a) endocrine gland synthesizes the hormone. b) Hormone diffuses into capillaries. c) Hormone is transported by blood or lymph toward target cells. d) Hormone diffuses out of capillaries at target tissue, and causes an effect in target cells. e) Some hormones act through receptors on the surface of target cells (peptide and amine hormones) f) Some hormones enters the cell and hormone receptor complex enters nucleus.

11. Chemistry of Hormones Hormones are organic compounds secreted by endocrine glands, that have a potent effect in target cells following are types of hormones: Protein Hormones (Peptide Hormones) Catecholamine Hormones Eicosanoid Hormones Steroid hormones Thyroid Hormones Hormones of Anterior and Posterior Pituitary

12. Peptide, catecholamine, and eicosanoid hormones act from outside the target cell via cell surface receptors. Steroid, vitamin D, retinoid, and thyroid hormones enter the cell and act through nuclear receptors. Nitric oxide (a gas) also enters the cell but activates a cytosolic enzyme, guanylyl cyclase .

13. Protein hormones Made of amino acids joined by peptide bonds (3-200 or more amino acids residues). Fat – insoluble; as a result cannot diffuse across the membrane of target cells. Most hormones belong to this group like Pancreatic Hormones: Insulin, glucagon and somatostatin Parathyroid, Hypothalmus , and pituitary Hormones

14. These hormones are synthesized on ribosomes ( prohormones ). Packaged into secretory vesicles and proteolytically cleaved to form the active peptides. Insulin two polypeptide chains linked with disulfide bond (synthesis in pancrease ) Preproinsulin Proinsulin

15. Mechanism of activation of hormone

16. General Mechanism of action of protein hormones At target cell, the protein hormone binds with a specific receptor embedded in the cell membrane of target cell. This binding activates a series of chemical reactions (“cascade reactions”) in the cytoplasm of target cell. The product of these reactions is a substance known as “secondary messenger” ( cAMP ), which acts on behalf of the protein hormone , causes a potent effect in the target cell (usually within the cytoplasm).

17. General Diagrammatic Representation

18. References D. Voet , J.G Voet and C. W. Pratt. 2016. Fundamentals of Biochemistry. 5 th edition. John Wiley and Sons. Inc. NY. D. L. Nelson and M. M. Cox. 2017. Lehninger Principles of Biochemistry. 7 th edition. Worth Publishers, New York. P. C. Champe ., R. A. Harvey and D. R. Ferrier. 2017. Biochemistry: Lippincott's Illustrated Reviews. 7 th edition. Lippincott Williams and Wilkins. U.S.A. Internet Source

19. Question & Answer Session Interactive Session