History of endocrinology-Lecture2 (2024).pptx

History of Endocrinology-How this field evolved into a science having application in the field of human health. The diagnosis, treatment methods evolved from very crude experiments to sensitive assays.

1. HISTORY OF ENDOCRINOLOGY Lecture 2

2. Historical Perspective

3. The Science of Endocrinology Progressed from simple observations to Complex Experimentation Infant Science until Berthold (1849) first recorded endocrinology experiments 50 years later (1889-1902) pace quickened After 1910 the outline of endocrine system in invertebrates and vertebrates was known Simple observations- organ transplant, replacement therapies, active extracts Development was enhanced due the advancement in chemistry, physiology, molecular biology, and genetics Elucidation of gene structure of hormones and their receptors

4. Berthold’s Experiments in Roosters Lead to the discovery of Testosterone

5. Compensatory Hypertrophy was observed

6. Secretin is Discovered by Bayliss and Starling Acid-> Denervated but vascularized section of jejunum-> secretion of pancreatic juice-> humoral not nervous Bayliss and Starling showed that it was a universal stimulant – secretin from one species would stimulate the pancreas of any other species Bayliss and Starling first communicated their discovery to the Royal Society only one week after the experiment ( Bayliss & Starling, 1902) and published the full account of the experiments leading to the discovery of secretin in The Journal of Physiology later that same year ( Bayliss & Starling, 1902).

7. The demonstration by Bayliss and Starling that acid liberates a chemical messenger from the cells of the duodenal and jejunal mucosa and that this, by traveling through the blood, excites the pancreas to secrete revolutionized physiology. It subsequently provided to establish endocrinology as a specialist field in medicine

8. Insulin is determined to be Pancreatic Hormone that regulates Blood Glucose Paul Langerhans

9. Benting and Best-islets of langerhans

10. The Nervous System is shown to release Neurotransmitters

11. Nobel Prize

12. Sutherland and Colleagues Discover Cyclic AMP Cyclic AMP is believed to be the intracellular agent which mediates the action of many hormones on their target cell.

13. Earl Sutherland and his colleagues 1962

14. Nobel prize in 1971

15. Discovery of Hypothalamic Releasing Factors starts a “Race to Stockholm” Nobel prize

16. Development of Immunoassays Permits Hormone Measurements at Physiological Concentrations

17. Boundaries of Endocrinology are broadened with the Discovery of Growth factors

18. Advances in Molecular Biology and Genetics Spawn a New Era in Endocrine Research Advent of recombinant technology lead to unparalleled era of progress Characterization, cloning, expression of genes encoding GH Structure and expression of genes encoding adrenal cortcorticoid hormones Use of embryonic stem cells for homologous recombination techniques Hormone receptor genes

19. Research Methodologies