logging in or signing up Physiology of Thyroid gland 9-10-2010 vijaykannan Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Copy Does not support media & animations WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 1641 Category: Education License: All Rights Reserved Like it (2) Dislike it (0) Added: December 01, 2010 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... By: docgreggy (22 month(s) ago) dear Dr. Kannan, Can you please allow me to download your presentation for educational purpose. Thank you Gregory Viste Saving..... Post Reply Close Saving..... Edit Comment Close By: Maizwafy (29 month(s) ago) Respected Sir, Permission may please be granted to down load the content for teaching purpose. Dr. Nistar Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Physiology of Thyroid gland : Moderator – Prof. Dr. G. Mohan M.S Presented by Dr. S. Vijay Kannan MS (Gen) PG Physiology of Thyroid gland The Thyroid : Uniqueness: Only tissue that can both concentrate and organify ingested iodide. Large store of hormone in extracellular depot contained within the follicles of the gland The Thyroid Histology : Histology Functional unit of thyroid gland – Acinus or thyroid follicle. Thyroid Hormones : Thyroid Hormones Hormones in circulation : Strongly bound to serum proteins Bound to ( in decreasing order of affinity) Thyroxine Binding Globulin Thyroxine Binding Pre Albumin Serum albumin Drugs competing with binding: Salicylates Hydantoins Diclofenac Hormones in circulation Free thyroid hormones : Majority of cells cannot take up in bound form. Normal individuals – Total thyroid hormones mirror the Free hormones In Altered binding protein concentration, Binding Proteins Bound T3 and T4 Binding Proteins Bound T3 and T4 Free thyroid hormones Slide 7: States of elevated Thyroxine Binding Globulins Pregnancy Estrogen therapy and oral contraceptives Hypothyroidism States of decreased Thyroxine Binding Globulins Protein malnutrition Cirrhosis Androgens Acute and chronic illnesses Hyperthyroidism Thyroid Hormones… : Thyroid Hormones… Synthesis of Thyroid Hormones : Synthesis of Thyroid Hormones Iodine Trapping : I- I- COLLOID BLOOD Iodine Trapping Factors affecting iodide [I-] uptake : Factors affecting iodide [I-] uptake Enhancers: TSH Iodine deficiency TSH receptor antibodies Autoregulation Inhibitors: I- excess Cardiac glycosides( Digoxin, Ouabain) Perchlorate Bromides & Nitrates Slide 12: Formation & Secretion of TG Oxidation of iodide ions & Iodination of TG Coupling : Coupling Storage & Release : Storage & Release TSH Peripheral conversion & Catabolism of T4 : Peripheral conversion & Catabolism of T4 PropylThiouracil Stimulators of T4 and T3 release : TSH VIP (vasoactive intestinal peptide) β-adrenergic agonists Long-Acting Thyroid Stimulators (LATS) / Thyroid Stimulating Immunoglobulins (TSI) Low temperature Stimulators of T4 and T3 release Regulation of Thyroid Hormones : Regulation of Thyroid Hormones Effect of TSH on Thyroid Gland : Effect of TSH on Thyroid Gland Physiological effects of thyroid hormones : Physiological effects of thyroid hormones Effect of Thyroid Hormones : Effect of Thyroid Hormones Slide 21: Metabolic Actions Slide 22: Metabolic Actions Action on specific organ Systems : Action on specific organ Systems Action on specific organ Systems : Action on specific organ Systems Pathophysiology : Pathophysiology Hypothyroidism : Hypothyroidism Hyperthyroidism : Hyperthyroidism Summary : Summary Regulated by the hypothalamic-pituitary-thyroid axis. Dietary iodine is required for thyroid hormone synthesis. Thyroid hormones undergo metabolism in peripheral tissues, leading to the production of the more active T3. Hormone receptors are located intracellularly, bound to DNA, and alter gene transcription upon binding by thyroid hormone. Hormone actions are systemic and vital for growth, development and metabolism. References : Essential Endocrinology (4th ed) Harrisons Endocrinology (16th ed) Medical Physiology by Kibble & Halsey Endocrine Physiology, 2nd Edition by Patricia E. Molina Medical physiology by Ganong References Thank you : Thank you You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.