Endocrine System Intro Flashcards
What are the sites called where chemical hormones have effect and how do they effect
Non adjacent sites via receptors
Why are target sites specific for hormones
Only target cells have the right receptors eg v2 on principal cells for ADH
What are produced in the adrenal glands
Catechol amines (nadr and adr)
Glucocorticoids (at Fasciculata and reticularis) and mineralocorticoid (glomerulosa)
Which hormones are produced by pancreas and what type are they
Insulin and glucagon
Both polypeptide hormones
Why is adipose tissue an endocrine tissue
It produces androgens which can be converted to oestrogen via aromatase
Which precursor produces steroid hormones and give examples
Cholesterol
Eg cortisol or sex hormones like oestrogen and testosterone
Why do steroidal hormones act on intracellular receptors
Lipophillic and hydrophobic
How can steroidal hormones be transcription inducers
When they bind they open hinge region so receptor can bind to Dna and recruit rna pol
Give examples of polypeptide hormones
Pituitary hormones stored as pre pro hormones eg tsh, fsh , act
ADH
Insulin/ glucagon
Name the 2 types of amino acids which produce hormones
Tyrosine - Dopamine , thyroxine , catecholamines
Tryptophan - 5HT
Which amino acid hormone is the only one acting on intracellular receptors
Thyroxine
Why are peptide/ aa hormones faster in response
Lipophobic and hydrophilic
They have GCPR which causes fast transduction signalling on cell surface
Which nuclei/ cell bodies connect hypothalamus to the posterior pituitary (produce ADH and oxytocin)
Supraoptic and paraventricular nuclei
Which cell bodies in hypothalamus produce trigger hormones to the anterior posterior to release more hormones
Parvocellular
Give examples of trigger hormones released down the hypophyseal tract to the anterior posterior
Gonadotropin RH
Corticotropin RH
GH RH
GH inhibitor
Dopamine
Thyrotropin RH
Name some hormones released at the anterior posterior
TSH
LH and FSH
Growth hormone
Prolactin
How does glucocorticoid affect metabolism as well as inflammatory response
Increases gluconeogenesis
Reduces uptake of glucose by liver
Increases sensitivity to nadr for glycogenolysis
What is the cortisol hypothalamus fight or flight response called
HPA axis
Explain the steps of how cortisol are released in stress from hypothalamus
Hypothalamus releases corticotropin releasing hormone
Goes down hypophyseal tract to anterior pituitary
Anterior pituitary produces and released adrenocorticotropin
Binds to adrenal cortex and allows production of cortisol from cholesterol
Why is corticotropin RH release called neuronal control
Hormone is released due to neuronal stimulation ie at the hypothalamus
Why is cortisol release tropic control
It is released due to stimulation by release of another (adrenocorticotropin)
Why is ADH control neuronal control
Because when BV/ osm are back to normal baroreceptors and osmoreceptors send stimulus to hypothalamus to stop ADH productjon from posterior pituitary
Why is blood glucose reg via insulin and glucagon at pancreas called substrate control
The A and B cells fill with glucose/ detect glucose levels which would then stop or increase release
How is entry of glucose to B cells allowing release of insulin
Glycolysis generates atp which blocks the K channel
This also stimulated ca channels to open and ca floods in
Ca flooding in causes vesicles with insulin the fuse and they get released
How can we interfere with endocrine system to stop things like Cushing syndrome
Interfere with
Synthesis
Release
Receptor agonist/ antagonist
Metabolism increase or decrease of hormone
Hormone replacement therapy
Why would corticoids be used to stop inflammation and bronchospasm
They block phospholipase A2
