Hypothalmic Pituitary Axis Flashcards
Describe the diifference of endocrine system and the nervous system
ES is longer term, with chemical messengers
NS is short term and specific with a neurotransmitter messenger
What are the 4 different hormone classes
Amino acid derived
Peptide/ protein
Steroid
Fatty acid
What are amino acid hormones derived from
Tyrosine
What are steroid hormones derived from
Cholesterol
what are fatty acid hormones derived from
Arachidonic acid
which hormone type are pituitary gland hormones
Peptide/ protein
What is endocrinopathy
Diseases of endocrine glands
(Hormone imbalances)
Which part of the brain is the hypothalamus in
Diencephalon
How does the hypothalamus communicate with the endocrine system
Through the pituitary gland (hypophysis)
How is the hypothalamus linked to the pituitary gland
Infundibulum
Which hormones are secreted by the posterior pituitary gland
ADH + Oxytocin
Describe the action of the pituitary portal system
Neurohormones from hypothalamus go to 1st capillary bed.
Neurohormones travel to 2nd capillary bed which surround anterior + intermediate pituitary lobes
Describe the action of ADH
Negative feedback!
When decrease in blood volume/ blood pressure and increase in osmolarity (animal is thirsty)
Stimulates ADH producing neutrons in hypothalamus, secreted by the Posterior PG.
Inserts aquaporins into the kidney so more water is reabsorbed.
What is the function of oxytocin
Positive Feedback!
Uterine and myoepithelial cell contractions
What type of hormones do the hypothalamus release to the pituitary gland
peptide
(Hypothalamic hypogastric hormones)
What are the 6 different hormones the anterior pituitary gland secrete
- FSH
- LH
- ACTH (adrenocorticotrophic)
- TSH (thyroid stimulating hormone)
- GH (growth hormone)
- PRL (prolactin)
Describe long loop feedback
Hormone released from endocrine gland communicates to hypothalamus to inhibit excess release of the initial hormone
Describe short loop feedback
Pituitary gland hormone communicates with the hypothalamus to stop secreting initial hormone
Describe ultra short feedback
Hormone secreted form endocrine organ communicates with that organ to stop releasing that hormone
How may amino acids make up oxytocin
9
How many amino acids make up growth hormone
191
What stimulates the release of groeth hormone
GHRH (growth hormone releasing hormone)
GHIH (growth hormone inhibiting hormone)
What hormone inhibits prolactin
Dopamine
What is the main function of the intermediate pituitary lobe
Melanocyte production (release Melanocyte stimulating hormone) and release from camouflage in reptiles, fish and amphibians
