Hormones

A hormone is a chemical messenger produced by a ductless gland which has its action at a distant target cell via a specific receptor.

• Lipid hormones, divided into:
  • Steroids
    Steroids are synthesised from cholesterol, and are released as they are produced (they are not stored). They are highly lipid soluble and act on cytoplasmic and intra-nucleic receptors.
    • Aldosterone
    • Testosterone
    • Oestrogen
    • Cortisol
  • Eicosanoids
    Eicosanoids are formed from cell membrane phospholipid.
    • Prostaglandins
    • Thromboxanes
    • Leukotrienes

• Peptide hormones
  Peptide hormones are store in granules and released by exocytosis. They are divided into:
  • Short-chain
    • Insulin
    • ADH
    • Oxytocin
    • ACTH
  • Long-chain
    • GH
    • Prolactin
  • Glycopeptides
    Proteins with carbohydrate groups.
    • LH
    • FSH
    • TSH

• Monoamine derivatives
  Derived from a single amino acid.
  • Catecholamines
    Stored in granules and act at membrane receptors.
    • Adrenaline
    • Noradrenaline
  • Serotonin
  • Thyroxine

References

1. Chambers D, Huang C, Matthews G. Basic Physiology for Anaesthetists. Cambridge University Press. 2015.