Historical perspective of endocrinology

1. Historical perspective of endocrinology

2. Beginning of science • When do scientific explorations begin? • Early science • Linked to medicine rather than intellectual curiosity • Some behaviors/traditions • No scientific understanding • Scientific merit

3. History of endocrinology • Blood drinking and organ eating • Gaining strength • Gaining advantage over enemy • Treatment for diseases (organotherapy) • Impotence • Endocrine disorders • What is in the blood? • Source of life (Leviticus 17:11)

5. Egyptians • Understanding the role of gonads (ovaries and testis) in sexual reproduction • Fertility and contraception • Removal of ovaries • No pregnancy • Removal of testis • Eunuchs serving in Pharaoh’s harem • Use of tampons as a contraceptive • Materials from male are responsible for pregnancy

6. Egyptians • Methods of pregnancy diagnosis • Morning sickness • Detection of diabetes • Excessive thirst • Laid the foundation

9. Greeks • Hippocrates (father of medicine) • First known physician • Many clinical Observations • Considered medicine as science and separated practice from religion

10. Greeks • Hippocrates • Theory of inheritance • Pangenesis theory (Seeds come from all parts of body and stored in testis) • Theory of four humors • Black bile, yellow bile, phlegm (green), and blood • Correction of health problems through balancing four humors • Sexing of offspring through testis removal • Right-male • Left-female • Identification of vascularized glands

11. Greeks • Aristotle • History of animals • Sows • Loss of ovaries via ovariectomy • Contraception • Increased growth • Argument against preformation theory • Embryo dissection • Methods of contraception • Diet (obesity/starvation) • Rhythm method • Ovariectomy • Vaginal and cervical environment manipulation

13. Romans • Organoectomy and organotherapy • Eating brain for epilepsy • Eating testis for impotence

14. Romans • Galen • Discovery of thyroid gland • Ductless gland similar to salivary gland • Vital spirit • Substances from brain being carried into the blood • Pituitary gland • Storage of waste products from brain

15. Romans • Galen • Peri Spermatos (on seed) • Castration • Decreased libido • Changed fat deposition • Changed hair distribution • Substance from testis affected physical characteristics

16. Middle ages • No significant progress in science • Domination of church • Diseases = act of God • Surgery = dirty medical practice • Chinese • Cure for Goiter • Consumption of seeweed and shellfish • Dysfunction of thyroid gland • Cause of diabetes

17. Chinese • Testicular organotherapy • Extraction of steroid and metabolites from urine • Varying drying temperature to isolate different steroids

19. Renaissance (rebirth) • Explosion of arts and science • Anatomy • Da Vinci and Michelangelo • Galileo Galilei • Development of miscroscope and telescope • Robert Hooke • Discovery of cells • Antoine van Leeuwenhoek • Discovery of sperms

20. Renaissance (rebirth) • William Harvey • Circulation of blood • Refuted preformation theory • Dissection of uterus immediately after mating • No congealed mass • No female/male parts • De Bordeaux (vitalist) • Emanation from each organ is crucial for health • No experiments

21. Renaissance (rebirth) • Discovery of iodine as a treatment for Goiter • Bernard Courtois

22. First endocrinology experiment

23. First endocrinology experiment • Hunter and Berthold • Growth of organs during transplantation • Rooster as a model

25. Removal of testis • Removal of male characteristics (comb) • Transplantation of testis • Normal male characteristics • Characteristics controlled by substance in blood, not by nerves • Completely disconnected testis

26. Contemporaries • Claude Bernard • Exocrine vs. Endocrine gland (liver) • Bile from gall bladder • Internal secretion (glucose from hepatic glycogen) • Thomas Addison • Link between adrenal dysfunction and blood • Addison’s disease (hypoadrenalism) • Brown-Sequard • Organotherapy • Extract from testis to rejuvenate older men

27. George Murray • Hypothyroid (myxoedematous) patients can be treated successfully with thyroid extract • Von Merring and Minkowski • Relationship between diabetes and pancreas dysfunction • Removal of pancreas resulted in constant urination • Urine from dogs attracted houseflies when their pancreas were removed

28. Hale White • Feeding pancreas/injection of pancreas extract to treat diabetes • Did not work (allergic reaction/too little insulin being stored in pancreas) • Pierre Marie • Pituitary gland tumor as a cause of acromegaly • Excessive growth hormone from tumor resulted in excessive growth • Feeding of dried pituitary gland • No effects on growth

29. Oliver and Schafer • Relationship between adrenal gland and blood pressure • Extract from adrenal medulla and pituitary gland caused increase in blood bressure • Extract from thyroid gland caused fall in blood pressure • “On Internal Secretion” (1895)

30. Discovery of the first hormone • Starling and Bayliss • Interaction between duodenum loop and pancreas • Passing of foodstuff (chyme, highly acidic) through duodenal loop stimulated release of enzyme by pancreas • Initial thought – nervous system (vagus nerve) • Denervated duodenum stimulated release of pancreatic enzymes when stimulated with acid • Chemical reflex rather than nerve reflex • Reaction through blood • Discovery of secretin

31. What is in the name? • Hormone • Greek “I excite” or “I arouse” • Transported by blood from one organ, which secretes the substance, to the organ where the effect is exerted