PHARMACY STUDENTS DECEMBER 2011 REV. PROF. A.S. AYETTEY

OBJECTIVES TO KNOW THE MAJOR ENDOCRINE GLANDS IN THE BODY BE ABLE TO DESCRIBE THE FUNCTION OF EACH OF THE MAJOR ENDOCRINE GLANDS TO BE ABLE TO APPRECIATE HOW THEIR FUNCTION IS REGULATED BE ABLE TO RELATE THE ENDOCRINE GLANDS AND THEIR FUNCTIONS TO CLINICAL PROBLEMS ASSOCIATED WITH THEM

THE MAJOR ENDOCRINE GLANDS PITUITARY SUPRARENAL GLANDS PANCREAS THYROID THYMUS GONADS GASTRO-INTESTINAL KIDNEYS

WHAT ARE ENDOCRINE GLANDS DUCTLESS GLANDS SMALL IN SIZE RELATIVE TO THEIR FUNCTIONAL ROLE INTHE BODY FEW IN NUMBER HAVE RICH BLOOD SUPPLY PRODUCE HORMONES RELEASE HORMONES INTO THE VENOUS SYSTEM SPECIFIC IN ACTION THROUGH RECEPTORS REGULATED THROUGH THE HYPOTHALAMUS FEEDBACK MECHANISM

THE PITUITARY GLAND MOST IMPORTANT ENDOCRINE ORGAN UNDER DIRECT CONTROL OF THE HYPOTHALAMUS RECEIVES RELEASING HORMONES FROM HYPOTHALAMUS SECRETES TROPHIC HORMONES SECRETIONS INFLUENCE HORMONE PRODUCTION IN ALL OTHER ENDOCRINE GLANDS

PARTS OF THE PITUITARY GLAND ADENOHYPOPHYSIS DERIVED FROM THE ROOF OF THE NASOPHARYNX LOCATED IN THE PITUITARY FOSSA (hollow pit) NOTE POSSIBILITY OF REMNANT OF PITUITARY TISSUE (and tumors) INTERMEDIATE LOBE ALSO DERIVED FROM ROOF OF THE NASOPHARYNX NEUROHYPOPHYSIS DERIVED FROM THE HYPOTHALAMUS AS PART OF THE BRAIN

FUNCTIONS OF THE ANTERIOR – ADENOHYPOPHYSIS - 1 PRODUCE STIMULATING HORMONES IN RESPONSE TO RELEASING HORMONES(factors) FROM THE HYPOTHALAMUS GROWTH HORMONE (SOMATOTROPIC HORMONE)– BONE GROWTH, ETC. (needed from embryo stage to adolescence to abt 21 yrs) THYROID STIMULATING HORMONE (from thyroid releasing factor)–BASIC METABOLISM (from hormones) ADRENO-CORTICO TROPIC HORMONE – ADRENAL CORTEX FUNCTION MINERALOCORTICOIDS (influence mineral synthesis) GLUCO-CORTICOIDS (influence glucose synthesis) SEX HORMONES (influence sex hormones)

FUNCTIONS OF THE ANTERIOR – ADENOHYPOPHYSIS 2 PROLACTIN INITIATION OF MILK SECRETION FOLLICLE STIMULATING HORMONE (important for fertilization) PRODUCTION AND MATURATION OF OVA LEUTENIZING HORMONE IN FEMALES STIMULATION OF OVARIAN HORMONES OESTROGENS - PROMOTE DEVELOPMENT OF FEMALE SECONDARY SEXUAL ORGANS (breasts and uterus) STIMULATES ENDOMETRIAL GROWTH (to prepare it for implantation) PROGESTERONE ENHANCES SECRETORY PHASE OF ENDOMETRIUM (placenta maintenance until term for birth) SUPPRESSES IMMUNE RECOGNITION OF THE FETUS IN IMPLANTATION SUPPRESSES UTERINE CONTRACTION DURING PREGNANCY IN MALES: LOW LEVELS ENHANCES MATURATION OF SPERMATOZOA

FUNCTIONS OF THE NEUROHYPOPHYSIS – THE POSTERIOR LOBE ANTI-DIURETIC HORMONE (ADH) (ALSO KNOWN AS VASOPRESSIN) STIMULATES KIDNEY TUBULES TO REABSORB WATER (at the distal convulated tubule) OXYTOCIN STIMULATES CONTRACTION OF SMOOTH MUSCLES ESPECIALLY IN THE UTERUS IN FINAL STAGES OF PREGNANCY (suppresses progesterone)

THE THYROID GLAND AND ITS FUNCTIONS 1 PRODUCTION OF TRI-IODOTHYRONINE (T3) MORE RAPIDLY ACTING PRODUCTION OF THYROXINE (T4) NOTE IMPORTANCE OF TYRONINE IODINE MAIN FUNCTION REGULATION OF METABOLISM RATE AT WHICH TISSUES UTILIZE FOOD TO PRODUCE ENERGY INFLUENCE BODY TEMPERATURE, HEART RATE, MOOD, SEXUAL STATE ETC.

THYROID FUNCTION 2 OTHER FUNCTIONS INFLUENCES FUNCTION OF ALL TISSUES INCLUDING OTHER ENDOCRINE GLANDS PRODUCTION OF CALCITONIN PARAFOLLICULAR BY PARAFOLLICULAR CELLS REDUCES LEVELS OF CALCIUM IN BLOOD OPPOSITE TO FUNCTION OF PARATHYROID HORMONES HYPERTHYROIDISM HYPOTHYROIDISM

PARATHYROID GLANDS FOUR IN NUMBER LOCATED WITHIN THE THYROID GLAND PRODUCE PARATHYROID HORMONE (PTH) DETECT CALCIUM LEVELS IN BLOOD REGULATE CALCIUM LEVELS IN BLOOD FOR NORMAL FUNCTION OF CELLS [local negative feedback mechanism] WHEN LEVEL IS HIGH, LOW PTH WHEN CALCIUM LEVEL (in blood) IS LOW, HIGH PTH (to remove from the bones) MAIN SITE OF ACTION - BONES HYPERFUNCTION RESULTS IN OSTEOPOROSIS

THE THYMUS GLAND AND FUNCTIONS VITAL IN LIFE ESPECIALLY IN CHILDHOOD ENDOWS T-LYMPHOCYTES WITH CAPACITY FOR CELLULAR IMMUNITY HELPING CELLS TO RECOGNIZE AND DESTROY INVADING BACTERIA VIRUSES CANCER CELLS FOREIGN TISSUE THE THYMUS AND MYASTHENIA GRAVIS NOTE THE PROBLEMS ASSOCIATED WITH EARLY REMOVAL OF THYMUS IMMUNE PROBLEMS

ADRENAL (SUPRARENAL) GLANDS SITUATED ON TOP OF KIDNEYS CORTEX STEROID HORMONES GLUCOCORTICOIDS GLUCONEOGENESIS IMMUNOSUPPRESSION ANTI-INFLAMMATORY MINERALOCORTICOIDS REGULATION OF WATER AND ELECTROLYTE LEVELS SEX HORMONES ANDROGENS ESPECIALLY TESTOSTERONE MEDULLA PRODUCTION OF ADRENALIN AND NORADRENALIN RELATED TO SYMPATHETIC FUNCTIONS

GONADAL HORMONES TESTICULAR SEX HORMONES TESTOSTERONE OVARIAN HORMONES (SECRETED BY FOLLICLE) ESTROGEN SECONDARY FEMALE CHARACTERISTICS MENSTRUAL CYCLE (PREPARING ENDOMETRIUM FOR IMPLANTATION) PROGESTERONE (SECRETAED BY FOLLICLE AND LATER BY PLACENTA) PREPARES FOR IMPLANTATION AND NOURISHMENT OF THE BLASTOCYST/FOETUS; PROMOTION OF MILK FORMATION TOGETHER INHIBIT OVULATION VALUE IN BIRTH CONTROL

OTHER HORMONAL GLANDS IN KIDNEYS ERYTHROPOIETIN(development and maturation of RBCs) IN THE GASTROINTESTINAL TRACT GASTRIN STIMULATES GASTRIC ACID SECRETION *PANCREOZYMIN* CHOLECYSTOKININ/*PANCREOZYMIN* STIMULATES SECRETION OF PANCREATIC ENZYMES STIMULATES CONTRACTION OF GALL BLADDER SECRETIN SECRETION OF WATER AND ELECTROLYES IN THE HEART ATRIAL NATRIURETIC HORMONES