Endocrine phys part 1 Flashcards
Where is a neurotransmitter released into
synapse
Where is a hormone released into
blood
Where is a neurohorome released to
blood
What is the signal type in the nervous system
frequency modulated
What is the signal type of endocrine system
amplitude modulated
Time course of nervous system vs endocrine system
Nervous: quickly on and quickly off
Endocrine/norendocrine: Slow on, slow off
Most common hormone types in the body
peptides (short chains of amino acids)
How do all peptides act
via cell membrane receptors (do not get inside of cell, act on surface)
What type of channel receptors are used for peptides
GPCR mostly
Do steroids and thyroid hormones act intracellularly or extracellularly
Intracellularly- bind to receptor and move to nucleus, activate or inactivate transcription
-Very small, diffuse through membrane
What is the humoral stimulus
Level of a substance stimulates a gland to release a hormone
What is a neural stimulus
Have a neuron directly stimulate a gland to release a hormone
What is a hormonal stimulus
Tropic hormones stimulate a gland to release another hormone
What is a tropic hormone that causes growth when they are released called
Trophic hormone
What type of feedback are hormonal stimuli typically
negative feedback loops
What is a tropic hormone
any hormone that triggers release of another hormone
Example of chronic hormone secretion pattern
Thyroid hormone
Example of acute hormone secretion pattern
Epinephrine during exercise (has stimulus)
Example of cyclic hormone secretion pattern
Cortisol during morning or estrogen in the menstrul cycle
What are 4 factors that dictate the circulating levels of hormones
- rate and pattern of secretion
- rate of degredation
- receptor binding
4.affinity to plasma carriers
What type of carriers do steroid hormones need
protein carriers (most bound to steroid binding proteins(SBP) or sex hormone binding globulin (SHBG))
What is the function of sex hormone-binding globulins
help with transportation, create resovoir
Can free or bound hormones act
only free hormones, not bound (when bound, inactive)
What part of the brain is the hypothalamus in
diencephalon
How does the hypothalamus control anterior pituitary
hormones (blood)
How does hypothalamus control posterior pituitary
neurons
Function of anterior pituitary
release hormones into blood
Function of posterior pituitary
neuroendocrine- release neurotransmitters into blood
function of capillary bed superior to the pituitary
pick up neural hormones from hypothalamus
Function of capillary bed in anterior pituitary
1.Drop off neurohormones from hypothalamus
2. pick up anterior pituitary hormones
Where are the posterior pituitary hormones made
hypothalamus
What are the 2 posterior pituitary hormones
ADH and Oxytocin
What is pitocin
synthetic version of oxytocin, stimulate contractions to induce labor