Hypothalamus and PItuitary Gland

• The Hypothalamus and pituitary gland


  Work together to control the functioning of many other glands
• The pituitary gland is often called the master gland
• The Hypothalamus and pituitary gland combined can be thought of as the command centre for the body
• Hypothalamus

  Has roles in both the nervous and endocrine systems and serves as a connection between the two systems
• Hypothalamus


  • Regulates basic functions of the body such as body temperature, water balance, and heart rate
  • Increases or decreases the secretions of other glands
  • Located at the base of the brain, below the thalamus and above the pituitary gland, about the size of an almond
• Functions of the hypothalamus

  1. Carried out through the pituitary gland

  2. Secretes releasing factors to stimulate the secretion of a hormone or inhibiting factors to slow down the secretion of a hormone

  3. Factors travel through blood vessels to the anterior lobe of the pituitary gland, affecting the secretion of hormones

  4. Other hormones are produced by the hypothalamus and pass along nerve fibres to the posterior lobe of the pituitary gland where they are released
• Pituitary Gland

  • Lies just under the hypothalamus and is joined to it by the infundibulum
  • Consists of an anterior lobe and a posterior lobe, each functioning separately
  • Anterior lobe has no nerves connecting it to the hypothalamus, connected by a network of blood vessels
  • Posterior lobe is joined to the hypothalamus by nerve fibres passing through the infundibulum
  • Not a true endocrine gland, it stores and releases hormones
• Anterior Lobe of the Pituitary Gland


  • Releases hormones that regulate a range of bodily activities
  • Controlled by releasing and inhibiting factors secreted by the hypothalamus
• Hormones released by the anterior lobe of the pituitary gland

  • Gonadotropins
  • Follicle Stimulating Hormone (FSH)
  • Luteinising Hormone (LH)
  • Growth Hormone (GH)
• Gonadotropins


  Affect the gonads, the ovaries, and testes
• Follicle Stimulating Hormone (FSH)


  • Stimulates development of follicles containing eggs in the ovary of females
  • In males, stimulates production and maturation of sperm in the testes
• Luteinising Hormone (LH)


  • In females, works with FSH to bring about ovulation and form the corpus luteum after ovulation
  • In males, stimulates interstitial cells in the testes to secrete male sex hormones
• Growth Hormone (GH)


  Also known as somatotropin
• FSH in females

  Stimulates the development of follicles in the ovary
• FSH in males


  Stimulates the production and maturation of sperm in the testes
• Luteinising Hormone (LH) in females


  Brings about ovulation and forms the corpus luteum after ovulation
• Luteinising Hormone (LH) in males


  Stimulates the interstitial cells in the testes to secrete male sex hormones
• Growth Hormone (GH)


  1. Stimulates body growth, particularly growth of the skeleton

  2. Increases the rate at which amino acids are taken up by cells and built into proteins

  3. Secreted throughout life to help maintain the size of organs once maturity is reached
• Thyroid-Stimulating Hormone (TSH)


  Stimulates the production and release of hormones from the thyroid gland
• Adrenocorticotropic Hormone (ACTH)

  Controls production and release of some hormones from the cortex of the adrenal glands
• Prolactin (PRL)


  Works with other hormones to initiate and maintain milk production in females
• The posterior lobe of the pituitary gland releases the hormones oxytocin and antidiuretic hormone
• Oxytocin (OT)
• Antidiuretic Hormone (ADH)
• The hypothalamus communicates with the pituitary gland through nerves and blood vessels in the infundibulum
• The hypothalamus secretes releasing factors into blood vessels heading towards the anterior lobe of the pituitary gland
• Releasing factors stimulate the release of a hormone from the anterior lobe of the pituitary gland
• Release of hormones

  1. The hypothalamus secretes releasing factors into blood vessels heading towards the anterior lobe of the pituitary gland

  2. Releasing factors stimulate the release of a hormone from the anterior lobe of the pituitary gland

  3. The pituitary gland releases factors that can release or inhibit the release of hormones from other glands

  4. If the infundibulum was severed there would be no release of pituitary hormones as they couldn’t pass down the infundibulum to the posterior or anterior lobes

  5. The posterior is an imposter gland as it does not produce hormones only stores and secretes them
• The anterior lobe of the pituitary gland produces and stores hormones
• The posterior lobe of the pituitary gland only stores hormones
• Anterior lobe of the pituitary gland


  Connected to hypothalamus via a network of blood vessels through the infundibulum
• Posterior lobe of the pituitary gland


  Special secretory nerve with cell body in hypothalamus. Hormones travel down nerve and are stored in the Posterior
• Anterior lobe of the pituitary gland


  • Cascade effect (enzyme amplification) caused by releasing factors and inhibiting factors
• Antidiuretic Hormone (ADH) and Oxytocin (OT) functions

  • Adrenal Cortex: secretion of hormones from the adrenal cortex
  • Mammary Glands: Milk Production
  • All cells: Growth and protein synthesis
  • Uterus and mammary glands: contractions of the uterus during childbirth and release of milk
  • Ovaries and testes: ovulation and maintenance of the corpus luteum, and secretion of testosterone
  • Kidneys: Reabsorption of water
  • Thyroid gland: secretion of hormones from the thyroid
  • Ovaries and testes: Growth of follicles and maturation of sperm
• Marginal utility

  • The additional utility (satisfaction) gained from the consumption of an additional product
• Follicle Stimulating Hormone (FSH) targets Gonads (ovaries and testes) and has different effects in females and males
• Luteinising Hormone (LH) targets
• Hormones released by the Anterior Pituitary

  • Growth Hormone (GH)
  • Thyroid Stimulating Hormone (TSH)
  • Adrenocorticotropic Hormone (ACTH)
  • Prolactin (PRL)
• Anterior Pituitary secretes hormones to regulate bodily activities


  Controlled by releasing and inhibiting factors secreted by the hypothalamus and carried by blood to the anterior lobe
• Growth Hormone (GH)


  • Stimulates body growth and in particular growth of skeleton
  • Increases rate amino acids are taken up by cells and built into proteins
  • Secreted throughout life to maintain size of organs etc