lecture 26 Flashcards
posterior lobe of the pituitary gland is connected to hypothalamus by what
neurons
where are the parts of the neurons found that connect posterior pituitary to hypothalamus
cell bodies in the hypothalamus, axons
terminate in the posterior lobe
what hormones does the posterior pituitary release
it releases ADH or oxytocin
where are the hormones ADH and oxytocin made and then what happens to them
Posterior pituitary hormones -
are made in the hypothalamus
(cell body of neuron), travel
down the axon, and are stored
at the axon endings until
required (peptide hormones).
what does Antidiuretic hormone do, ADH
stimulates the kidneys to reabsorb water
what does oxytocin do
stimulates the contraction of uterine muscles during
childbirth (an example of positive feedback)
* stimulates milk release in breastfeeding (milk ejection reflex)
how is the anterior pituitary connected to the hypothalamus
by portal blood vessels
what is a portal blood vessel
Portal blood vessels are blood vessels that go from one organ to another then to the heart. One example of this is the one that runs from the hypothalamus to the anterior lobe of the pituitary.
how does the hypothalamus communicate with the anterior pituitary gland
The stimulus for the communication is neural input to the hypothalamus.
Hypothalamus signals the anterior pituitary to release hormones by hormonal stimulation, secreting stored releasing hormone or stored inhibiting hormone, in the hypothalamus.
The released hormone binds to receptor on the membrane of a specific cell in the anterior lobe. The specific interaction causes a specific pituitary hormone to be secreted. Could be Prolactin or Growth hormone.
when is growth hormone concentration the highest
highest during night but fluctuates throughout the day.
growth hormone secretion is highest in what age group
in children and peaks in puberty, declines with age
we sleep a lot when injured why?
As more sleep causes the most GH to release, things heal faster during sleep, when GH is released.
