Endocrinology Basic Principles Flashcards
What does the endocrine system regulate?
Growth
Appetite
Sexual Development etc.
What are the key steps in diagnosing endocrinological disorders?
Good history taking Clinical observation Attention to detail Understandng the physiology Multi-disciplinary working
What are the major endocrine glands?
Thyroid Pituitary and Hypothalamus Adrenal Calcium/Parathyroid Pancreas Reproductive
What are the basic hormone subtypes?
Protein and Peptide hormones
Amino acid hormones
Steroid hormones (Lipid derived)
Give examples of protein and peptide hormones…
Oxytocin
Growth hormone
FSH
Give examples of amino acid derived hormones…
Adrenaline - modified tyrosine
Melatonin - modified tryptophan
Give examples of lipid derived hormones…
Testosterone
Oestradiol
(These have a cholesterol backbone structure)
What are the different types of hormone receptors?
G-protein couples receptors
Receptor tyrosine kinases
Receptors associated with tyrosine kinase activity
Steroid hormon receptors
What are some features of g-protein coupled receptors?
7 transmembrane domain
Associated g-protein complex
Activate signalling cascades
What is the major role of g-protein coupled receptors within endocrinology?
Main sensors of the internal environment
What is the extracellular function of g-protein coupled receptors?
Associated with ligand binding
What is the intracellular function of g-protein coupled receptors?
Associated with intracellular signalling
What diseases can result from a loss of function of the g-protein coupled receptor - lutenizing hormone receptor?
Familial hypogonadism
Leydig cell hypoplasia (males)
Primary amenorrhoea
What diseases can result from a loss of function of the g-protein coupled receptor - thyrotropin-releasing hormone receptor?
Central hypothyroidism
What diseases can result from a loss of function of the g-protein coupled receptor - growth-hormone-releasing hormone receptor?
Short stature (growth hormone deficiency)
What diseases can result from a loss of function of the g-protein coupled receptor - calcium-sensing receptor?
Benign familial hypocalciuric hypercalcaemia (FHH)
Neonatal severe primary hyperparathyroidism
What are receptor tyrosine kinases?
These are single subunits with a hydrophobic, transmembrane domain
e.g. insulin receptor
What are tyrosine kinase activity linked receptors?
Cytokine Receptor
e.g. Prolactin receptor; growth hormone receptor
They have involved JAK-STAT signalling
Where are steroid hormone receptors?
These are typically intracellular - either in the cytoplasm or nucleus
Why are steroid hormone receptors intracellular?
Steroid hormones are lipids and are therefore able to diffuse across the plasma membrane more freely.
What is the process of steroid hormone receptor activation?
- The steroid hormone diffuses across the plasma membrane.
- This binds to a cytoplasmic receptor to form a steroid-receptor complex.
- This binds to DNA response elements.
- This results in a change in gene transcription