Principles of Endocrine Control Flashcards
Define glands:
Epithelial tissue derivatives specialised for secreting
Define secretion:
By chemical release from a particular type of cell upon stimulation
Define endocrine:
Internal secretion where secretion enters bloodstream (ductless glands)
Define exocrine:
Glands with ducts which channels it secretion
What sort of gland is the pancreas?
Exocrine and endocrine
Define hormone:
Chemical messengers secreted into the blood by endocrine glands in response to signal exerting their effect on the target cells have receptor that bind with the hormones
What are the two main subjects that we classify hormones on?
- Based on solubility
- Based on structure
How do we class hormones based on their solubility?
- hydrophilic or water-soluble (peptides and catecholamines, adrenaline and noradrenaline)
- Lipophilic or lipid soluble (Steroid and thyroid hormones)
How do we class hormones based on their structure?
- Peptides (chain of specific amino acids)
- Amines (derivatives of amino acids, tryptophan or tyrosine)
- Steroids (Cholesterol derived lipids)
How are peptide produced?
Normal protein synthesis
How is steroids produced?
Modification of cholesterol molecule by enzymes
How do peptides travel in the body?
Blood in solution
How do steroids travel in the body?
Blood bound to plasma proteins
Can peptides enter cells?
No as lipid bilayer cell membrane
Can steroids enter cells?
Yes, easily
How do peptides effect a cell if they can’t enter on?
They bind to cell surface receptors
Does peptides or steroid bind to an intracellular receptor?
Steroids
What do peptides do?
Tigger event on inside surface of membrane
What do peptides act as?
Second messenger system
What do steroids do?
Act on DNA to alter cell function
Which is fast acting steroids or peptides?
Peptides
Which is slow acting steroids or peptides?
Steroids
What are examples of peptide hormone signal transduction?
-Cyclic AMP
-Protein kinase activity
-Calcium/Phosphoinostides
Cyclic GMP
What kind of receptors fo cyclic AMP, cyclic GMP and calcium ions have?
G-protein coupled receptors
Give an example of G-protein coupled receptors for cyclic AMP?
Adrenaline, noradrenaline,
glucagon, FSH, LH, TSH, Calcitonin,
parathyroid hormone, antidiuretic
hormone (ADH)
Give an example of G-protein coupled receptors for cyclic GMP?
Atrial naturetic hormone, nitric oxide
What kind of receptors fo protein kinase
insulin, prolactin and growth hormones
Give an example of G-protein coupled receptors for calcium ions?
Adrenaline, noradrenaline,
angiotensin II, ADH, GnRH, TRH
Finish the sentence:
Activation of the secondary messenger is a….
universal mechanism
What is the secondary messenger used by?
variety of extracellular messengers in addition to hydrophilic hormones
How does a steroid hormone work?
- Hormone passes through cell membrane
- Binding to transcription control of gene
- Transcription beings
- mRNA produced
- Leading to cellar response