Endocrine Overview 2 Flashcards
Overall function of hypothalamus in relation to endocrine system
Hypothalamus controls function of endocrine organs by neural and hormonal pathways
Hypothalamic-pituitary interface
What is the hypothalamic-pituitary interface?
Where the endocrine system meets the nervous system
hormone synthesis and release - hypothalamus
Hypothalamus can synthesize and release hormones from axon terminals directly into bloodstream
What are neurohormones?
- Hormones that can stimulate the neural mechanism
- Ex. ACH is classified as both an NT and a neurohormone
There are multiple feedback systems in place with the hypothalamic-pituitary system to:
Keep hormones at normal levels
What has given rise to the field of psychoneuroimmunology (PNI)?
Connections between endocrine-nervous-immunologic systems
Hypothalamic-pituitary system: Functions
- integration of neurologic and endocrine system
- hypothalamus to anterior pituitary
- hypothalamus to posterior pituitary
How does the hypothalamus connect to the anterior pituitary and what does it do?
- via capillary portal system
- makes hormones
How does the hypothalamus connect to the posterior pituitary and what does it do?
- via a series of nerves
- stores hormones
The hypothalamus synthesizes and releases _______ that regulate _________
- hormones
- gland secretion
How do steroids disrupt the HPA axis?
By suppressing hypothalamic-pituitary secretion
What problems can occur when there is too rapid or abrupt withdrawal of exogenous steroid?
- Result can be life-threatening adrenal insufficiency
- There is not enough time to recover sufficiently to stimulate cortisol secretion
What are the hypothalamic hormones? (5)
- GnRH
- CRH
- TRH
- GHRH
- PIH
GnRH =
Gonadotropin releasing hormone
GnRH stimulates:
- LH
- FSH
