Endocrine system.txt

  1. Endocrine messenger system
    second-messenger system of the body after the nervous system
  2. Hormone types
    • AMINO ACID Based: include proteins, peptides and amines
    • STEROIDS: made from cholesterol
  3. What hormones affect
    certain tissues or TARGET cells or TARGET organs
  4. Target cells
    Specialized by the cells having specific protein RECEPTORS
  5. 2 Mechanisms of hormone action
    • 1. DIRECT Gene activation: steroid hormone action, slower of the two
    • 2. Second-messenger system: non-steroid hormone BINDS to a membrane receptor and gives off a message which activates an enzyme IN the cell
  6. Anterior Pituitary that effect NON-endocrine targets
    • All Non-steroid (proteins)
    • GH - Growth Hormone: Stimulates GROWTH of muscle & bones. REGULATED by hypothalamic releasing & inhibiting hormones
    • PRL - Prolactin: Stimulates MILK production. REGULATED by hypothalamic hormones
  7. Anterior Pituitary that stimulate endocrine glands (TROPIC hormones)
    • All Non-steroid (proteins)
    • FSH Follicle-stimulating hormone: Stimulates PRODUCTION of OVARIES and SPERM. REG by Hypothalamic hormones
    • LH - Luteinizing hormone: Stimulates OVULATION of eggs (females) and TESTOSTERONE (males). REG by Hypothalamic hormones
    • TSH - Thyroid Stimulating Hormone: stimulates Thyroid Gland growth and activity. REG by Thyroxine in blood. REG by Hypothalamic hormones
    • ACTH - Adrenocorticotropic hormone: Stimulates ADRENAL Cortex to Secrete GLUCOCORTICOIDS. REG by Glucocorticoids & Hypothalamic hormones
  8. Posterior Pituitary
    • Oxytocin: non-steroid (peptide), stimulates CONTRACTION of uterus and breast milk. REGULATED by nervous System (hypothalamus)
    • Antidiuretic Hormone (aka vasopressin): non-steroid (peptide), promotes H20 RETENTION by kidneys...can cause INCREASE IN BP from vasoconstriction. REGULATED by hypothalamus in response to SALT imbalance
  9. Thyroid Gland
    • 2 iodine-containing hormones: T3 (triiodothyronine)- converts to T4 @ target tissues. T4 (thyroxine)- secreted by thryroid follicles
    • T3/T4: non-steroid (amine). Stimulates METABOLISM. REG by TSH
    • Calcitonin: non-steroid (peptide). Stimulates OSTEOBLAST activity, LOWERING blood Ca levels. REG by Ca levels in blood.
  10. Thyroid hormone DISORDERS
    • GOITERS: Thyroid Gland ENLARGES (swollen neck) from Lack of IODINE
    • CRETINISM: Due to HYPOsecretion of T4 (thryoxine) resulting in DWARFISM during childhood
    • MYXEDEMA: Due to HYPOthyroidism in adults..results in physical & mental SLUGISHNESS
    • GRAVE's DISEASE: Caused by HYPERThyroidism..results in INCREASED metabolism, heat intolerance, rapid heart beat, exophthalmos
  11. Parathyroid Gland
    PTH - Parathyroid hormone: non-steroid (peptide). Stimulates OSTEOCLAST activity to RAISE blood Ca levels; stimulates kidneys & intestines to ABSORB more Ca. REG by Ca levels in blood.
  12. Hypothalamus
    • Hormones produced: Oxytocin & ADH...to be released by the Post Pituitary
    • Releasing and inhibiting hormones that REGULATE the anterior Pituitary
  13. Thymus
    Thymosin: non-steroid (peptide). Produces types of WBC's, develops immune system by programming T lymphocytes
  14. Pancreas
    • Insulin: non-steroid (protein). Work to lower blood glucose levels by allowing glucose to CROSS PLASMA membrane into cells from BETA cells. REG by blood glucose levels
    • Glucagon: non-steroid (protein). Work to Raise blood glucose levels by allowing glucose to ENTER blood from ALPHA cells. REG by blood glucose levels
  15. Adrenal MEDULLA
    Norepi & Epinephrine(adrenaline): non-steroid (amines). Raise Blood glucose level, INCREASE metabolism, Constrict blood vessels, Dialate lung passageways. REG by Sympathetic nervous system
  16. Adrenal CORTEX
    • Glucocorticoids: STEROID hormones. Stimulated by INCREASED blood glucose. REG by ACTH (tropic hormone)
    • Mineralocorticoids: STEROID hormones. Promote REABSORPTION of Na and EXCRETION of K in kidneys. REG by changes in blood pressure/volume/Na & K levels
  17. Adrenal Cortex DISORDERS
    • Addison's disease: weak muscles and Bronze skin tone from lack of hormones
    • Hyperaldosteronism: can be due to ACTH-releasing TUMOR. Excess water & Na retained..lead to High BP & Edema
    • Cushing's syndrome: from tumor in middle area of cortex. 'Moonface,' 'buffalo hump' on upper back, High BP, hyperglycemia, weakening of bones, depression
  18. Mineralocorticoids
    • Mainly consist of ALDOSTERONE, goal to REGULATE mineral content in blood
    • REGULATES water & electrolyte balance
  19. Glucocorticoids
    • Cortisol & Cortisone: released in response to INCREASED blood levels of ACTH (ACTH stimulates release of these glucocorticoids)
    • Produces in Middle layer of cortex
    • Aids with Normal cell metabolism
    • Aids in resisting long term stressors
  20. Gonads
    • All these gonadotropic hormones are REG by FSH and LH (in Ant pituitary) by NEGATIVE feedback
    • Testes: Produce sperm & secrete ANDROGENS (STEROID hormones)such as testosterone. Support SPERM formation and Devel. of 2ndary SEX characteristics
    • Ovaries: Produces eggs & secretes ESTROGENS and PROGESTERONES (STEROID Hormones).
    • Est & Progest Stimulate growth of UTERINE lining. PROGEST gets breasts ready for LACTATION & helps implant EMBRYO in uterus. ESTROGEN involved in development of 2ndary SEX characteristics (breast), regulates menstrual cycle.
  21. Which are STEROID hormones vs. non-steroid
    • Gonad hormones in testes (androgens) & ovaries (estrogen & progesterone) & Adrenal Cortex hormones (Glucocorticoids & Mineralcorticoids) are the only STEROID hormones.
    • Everything else is non-steroid
  22. Pituitary Gland Facts
    • Hangs by a stalk from the HYPOTHALAMUS in brain
    • ANTERIOR pit: composed of GLANDULAR tissue
    • POSTERIOR pit: composed of NERVOUS tissue
    • Often called the 'master endocrine' gland
  23. Anterior Pituitary facts
    • Mostly are regulated by negative feedback
    • Since all are non-steroid (proteins), act through Second Messenger Systems
  24. Growth Hormone (GH) Facts
    • Metabolic Hormone
    • Effects related to growth of muscle and long bones
    • Causes AA's to be built into PRoteins
    • Causes fats to be broken down as ENergy source
  25. Growth Hormone Disorders
    • Pituitary Dwarfism: hyposecretion of GH during childhood
    • Gigantism: hypersecretion of GH during childhood (does not include enlarged organs, so organs can fail due to the increased stress put upon them)
  26. Pineal Gland
    • On 3rd ventricle of brain
    • Secretes MELATONIN
    • Helps establish the body's SLEEP & Wake cycle
Card Set
Endocrine system.txt
anat endocrine