Basic principles Flashcards
What are the endocrine glands?
Hypothalamus Pituitary gland Parathyroid Thyroid Adrenal Ovaries Testes
What are the three classes of hormone?
Proteins/peptide
Steroid
Tyrosine/tryptophan derived
What are protein hormones and give two examples?
AA chains of varying lengths
Insulin
GH
What are steroids and give two examples?
Derived from cholesterol
Cortisol
Testosterone
Give two examples of tyrosine derived hormones.
Adrenaline
Thyroid hormones
What are the four types of hormone receptor?
GPCR
Receptor tyrosine kinase
Receptor associated with tyrosine kinase activity
Steroid Hormone receptors/nuclear receptors
Describe steroid hormone receptors.
Nuclear receptors found in cytoplasm or nucleus
Describe receptor tyrosine kinase receptors
Ligand binding causes autophos thus recruiting signalling molecules.
Describe receptor associated with tyrosine kinase activity
Cytokine receptors
Describe GPCRs
When ligand binds GTP replaces GDP on alphaSU allowing alpha and beta/gamma disassociation.
What are the three major kinds of GPCR?
Gs
Gi
Gq
How do Gs and Gi work?
Stim or inhibit Adenylyl Cyclase which converts ATP to cAMP -> activates PKA which phos Ser/Thr
How does Gq work?
Stim Phospholipase C to convert PIP2 to IP3 allowing Ca release. PLC stim DAG to stim PKC to phos Ser/Thr
What are the main factors to hormone conc?
Pattern of secretion- most important Carrier proteins Interfering agents Half life Absolute conc
How is hormone release generally controlled?
Negative feedback.
