endocrine system

• endocrine glands

  pineal, pituitary, thyroid, parathyroid, adrenal
• hormones

  chemical messengers that are released into ECF, diffuse into blood stream and are transported by the cardiovascular system around the body
• synergistic hormones

  work together
• antagonistic hormones

  work against eachother
• paracrine

  local hormone, released by a cell and affects nearby cells with receptors for paracrine
• autocrine

  local hormone released by a cell and affects the same cell, which has receptors for autocrine
• adrenaline is an amino acid derived hormone and is sythesised from tyrosine
• hormones may be free in plasma or bound to plasma proteins
• thyroxine is an amino acid derived hormone sythesised from tyrosine
• thyroxine actions

  increase glucose catabolism, basal metabolic rate, heat production, and promotes development or nervous and musculoskeletal systems
• cholesterol derived hormones

  steroids and aldosterone
• aldosterone

  from adrenal cortex, increases sodium reabsorption and potassium secretion by the kidneys
• arachidonic acid derived hormones

  eicosanoids
• PGE2

  eicosanoid that increases body temp, causes vasodilation, and uterine contractions
• peptide hormones

  vasopressin and oxytosin, and are produced by hypothalamus
• vasopression actions

  stimulates water reabsorption by kidney tubules and vasoconstriction
• protein hormones

  growth, thyroid stimulating, fsh, produced by anterior pituitary glands
• FSH

  ovary maturation, oestrogen production, sperm production
• water soluble hormones

  adrenalin, adh, fsh
• lipid soluble hormones

  steroids, vitamin D, thryoxine
• ADH is produced by the hypothalamus in response to high osmolarity or low blood pressure
• adrenal medulla releases adrenalin and noradrenaline in response to sympathetic nervous system activation
• adrenal cortex releases cortisol in response to ACTH from anterior pituitary, ACTH is released in response to CRH
• anterior pituitary gland

  releases hormones that affect other endocrine glands
• endocrine gland

  target gland of anterior pituitary hormone
• hypothalamus - pituitary - endocrine axis (thyroid)


  hypothalamus - TRH - anterior pituitary - TSH - thyroid gland - T4 and T3 - target organs or back to hypothalamus
• hypothalamus - pituitary - endocrine axis (adrenal)

  hypothalamus - CRH - Anterior pituitary - ACTH - adrenal gland - cortisol - target organs or back to hypothalamus
• primary dysfunction

  developmental, gene mutations, pathological
• secondary dysfunction

  problem with hypothalamus or pituitary
• hormone resistance

  dysfunction of receptor, signal transduction pathways, or mediator
• primary hypersecretion

  tumour, autoimmune stimulation or gene mutations
• secondary hypersecretion

  excess secretion of regulator from pituitary or hypothalamus
• insulin hypersecretion

  type 1 diabetes
• insulin resistance

  type 2 diabetes
• growth hormone hypersecretion

  gigantism
• leukotriene B4

  arachidonic acid derived
• aldosterone

  cholesterol derived
• adrenaline

  amino acid derived
• anti diuretic hormone

  peptide
• thyroid stimulating hormone

  protein