Pituitary Gland Control Flashcards
What does the hypothalamus produce to stimulate the anterior pituitary?
Produces several different hormone releasing factors which activate the anterior pituitary to release hormones into circulation
Can hormones from the basomedial hypothalamus reach the anterior pituitary?
Yes, they have to travel through the hypophyseal portal system
How does the anterior differentiate from the posterior?
Anterior: Separate from the brain, only responds to the brain through hormone signals sent through circulation
Posterior: Is connected/part of the brain. Direct intervention
What is the basomedial hypothalamus and what does it do?
Neurons toward the base/ mid of the hypothalamus are responsible for producing hormone releasing factors to communicate with the anterior pituitary via the hypophyseal portal system
What is the posterior pituitary composed of?
The axon terminals of the paraventricular and supraoptic neurons
Where are the cell bodies located of the neutrons that make up the hypothalamus?
Located in the Supraoptic and paraventricular nuclei in the bottom of the hypothalamus
What is the pathway in which hormones are released from the posterior pituitary?
Hormones are made and packed into vesicles in the cell body of the neuron located in the hypothalamus. Vesicles are transported down the axon into the posterior pituitary. Hormones are related directly into circulation
How do the supraoptic and paraventricular nuclei interface with the pituitary?
Both nuclei can produce and release both hormones
Which hormones are produced by the supraoptic and paraventricular nuclei?
Vasopressin (ADH)
Oxytocin
-both released right into circulation
What is meant by a neural-humeral reflex?
A stimulus activates a nerve ending, which activates a neural pathway to release a hormones into circulation
-the sensory info goes to the thalamus
What is an example of a neural-humeral reflex?
Breast feeding.
Baby suckling triggers mechanoreceptors in the Brest which send sensory information to the thalamus. This trigger hormone releasing factors to be released from the hypothalamus and sent to the anterior pituitary which releases another hormone into circulation(Prolactin). This stimulates milk secretion. At the same time neutrons in the hypothalamus are realizing oxytocin right into circulation to stimulate the smooth muscle contraction in the Brest to release the milk
What is breast feeding an example of?
Sexually dimorphic pathway in the brain
-there is a difference between males and female pathways
What happens to this pathway in women who aren’t pregnant?
The information from the thalamus never gets to the paraventricular and supraoptic nerves. Information doesn’t pass through here when she isn’t pregnant
-When the female is pregnant new connections are formed to make this pathway so the baby can be breastfed
What do we call female brains because of the connecting of new pathways in the brain?
The female brain has plasticity (ability to change)
