Cut,:

• Endocrine system


  Series of ductless glands that release chemical signals in the form of hormones into the bloodstream to stimulate another target tissue
• Glands of the endocrine system

  • Hypothalamus
  • Pituitary gland (Master gland)
  • Thyroid glands
  • Adrenal glands
  • Testes
  • Ovaries
  • Mammary glands
• Hormones


  Chemical signals released into the bloodstream by ductless glands, based on molecular composition
• Hypothalamus


  • Central operating unit that acts as the mediator between the endocrine system and nervous system
  • Directly commands the pituitary gland (master gland)
  • Detects abnormal hormone concentration and makes adjustments
  • Closely located to the pituitary gland
• Hypothalamus vs Pituitary gland (master gland)

  Hypothalamus detects abnormality, produces hormone to tell pituitary gland what to produce, pituitary gland does not produce randomly but under strictly controlled conditions
• Hormones synthesized by the hypothalamus

  • TRH
  • CRH
  • ADH/AVP
  • Oxytocin
• TRH


  Directly targets the pituitary gland, synthesized by hypothalamus if there is a decrease in T3 or T4 concentration
• CRH


  Directly targets the pituitary gland, synthesized by hypothalamus in response to low blood sugar
• ADH/AVP


  Antidiuretic hormone that directly stimulates the kidney to prevent urination, synthesized by hypothalamus
• Oxytocin


  Synthesized by hypothalamus, stimulates lactation and uterine contraction
• Nephron


  Functional unit of the kidney with 5 different parts
• Hyperosmolarity


  Primary stimulus for hypothalamus to produce AVP, caused by abnormal increase in Na, glucose, and urea
• Hormones of the anterior pituitary gland

  • Growth hormone (GH)
  • TSH
  • ACTH
  • FSH & LH
  • Prolactin
• Growth hormone (GH)


  Synthesized by anterior pituitary, stimulates growth of various tissues, affected in dwarfism, gigantism, and acromegaly
• TSH


  Thyroid stimulating hormone that targets the thyroid gland to produce T3 and T4
• ACTH


  Hormone that stimulates the pituitary gland to produce ACTH, targets the adrenal cortex to produce cortisol
• FSH & LH


  Stimulating hormones that target the testes and ovaries
• Prolactin


  Synthesized by pituitary gland, stimulates mammary gland to produce milk
• Hormones of the posterior pituitary gland

  • ADH/AVP
  • Oxytocin
• ADH/AVP


  Antidiuretic hormone that regulates blood pressure, body temperature, and social behaviours in males
• Oxytocin


  Releases milk
• Disorders of the posterior pituitary gland

  • Diabetes insipidus (low ADH/AVP)
  • SIADH (overproduction of ADH)
• Diseases of the thyroid gland

  • Primary hypo/hyperthyroidism
  • Secondary hypo/hyperthyroidism
• Primary hypo/hyperthyroidism


  Problematic organ is the thyroid gland
• Secondary hypo/hyperthyroidism


  Normal thyroid gland, abnormal pituitary gland
• Layers of the adrenal cortex

  • Zona glomerulosa
  • Zona fasciculata
  • Zona reticularis
• Zona glomerulosa


  Responsible for salt control, synthesizes aldosterone
• Zona fasciculata


  Responsible for glucose control, synthesizes cortisol
• Zona reticularis


  Synthesizes small amounts of sex hormones
• Adrenal medulla


  Synthesizes epinephrine and norepinephrine, responsible for fight or flight response
• Aldosterone


  Hormone that retains sodium in the bloodstream while excreting potassium
• Adrenal gland zones


  • ZG
  • ZR
  • ZS
• Adrenal gland zones


  • ZG produces aldosterone
  • ZF produces cortisol
  • ZR produces sex hormones
• Adrenal cortex


  • Outermost layer is ZG
  • Responsible for salt control
• Hormone responsible for milk production

  Prolactin
• Hormone responsible for milk release

  Oxytocin
• Concentration in patients with primary hyperthyroidism

  TSH - decrease<|>T3 - increase<|>T4 - increase
• Concentration in patients with secondary hypothyroidism

  TSH - increase<|>T3 - decrease<|>T4 - decrease
• Types of biomolecules


  • STEROID
  • AMINE
  • GLYCOPROTEINS
  • POLYPEPTIDES
• Hormones from the hypothalamus

  • GnRH
  • CRH
  • TRH
  • GHRH
  • GnIH
  • CIH
  • TIH
  • GHIH