Endocrine Test 1 Flashcards
What are the major targets of growth hormone in the body?
Adipose, liver, pancreas
What endocrine gland secretes prolactin?
Pituitary gland
Name the regulators of prolactin
- Where are these regulators secreted from?
- What is their effect ton prolactin?
Dopamine(hypothalamus) - restrains prolactin production - so the more dopamine the less prolactin
estrogen/oestrogen - increases the production and secretion of prolactin - *higher levels of this seen in women’s blood during menstruation
Where is ADH made?
Hypothalamus
The nerve cells transport ADH from the hypothalamus to where? Then where is it released?
Posterior pituitary then released into the blood stream
Important role of ADH
- helps control blood pressure by acting on the kidneys and the blood vessels
- conserve the fluid volume in the body
Higher concentrations of ADH cause blood vessels to _________ and this ________ blood pressure
cause blood vessels to constrict (get narrower) and this causes the blood pressure to increase
How is oxytocin secretion activated?
Stimulation of sensory neurons in the mammary glands and uterine cervix - triggers spinal sensory pathways which activate specific hypothalamic neurons via action potentials - released from the posterior pituitary
Oxytocin can be inhibited by what two factors?
Stress and alcohol
What are the two actions of oxytocin?
Stimulates contractions of smooth muscle with in the reproductive tracts as well as the mammary glands.
What is the effect of plasma proteins bound to hormones?
hormones are related to the tissue cells slowly
What hormones does the Anterior Pituitary secrete?
ACTH TSH FSH LH PRL GH
What hormones does the posterior pituitary secrete?
ADH and oxytocin
What hormones does the hypothalamus secrete?
thyrotropin releasing hormone, corticotropin releasing hormone, growth hormone releasing hormone, growth hormone inhibitory hormone, GnRH, PIH
What hormone does the pineal gland secrete?
Melatonin
What hormones act directly on peripheral target cells?
Prolactin, growth hormone, melanocyte stimulating hormone
What hormones act directly on other endocrine organs?
thyroid stimulating hormone, adrenocorticotrophic hormone, follicle stimulating hormone, luteinizing hormone, prolactin, growth hormone
What are the two factors that control growth hormone secretion?
Growth releasing hormone and growth hormone inhibitory hormone (somatostatin)
AKA for somatostatin
Growth hormone inhibitory hormone
What is the job of a somatomedin?
Protein that is a growth stimulating substance - Growth home cause the liver to form several small proteins that have the potent effect of increasing all aspects of bone growth
AKA for somatomedin
Insulin-like Growth Factors (IGFs)
Production of somatomedin will inhibit or stimulate GH secretion?
inhibit - because you won’t need as much of it
Somatomedian (IGF-I) are highly bound to plasma proteins
TRUE
How does growth hormone work in the body?
It does not function through a target gland but exerts its effects directly on all or almost all tissues of the body
Function of growth hormone?
promotes increased sizes of the cells and increased mitosis, and specific differentiation of certain types of cells such as bone growth cells and early muscle cells - growth of most cells and structures
Excessive GH excretion is due to what?
If it occurs in children what is it called?
If it occurs in adults what is it called?
Due to pituitary adenoma (benign tumor)
Causes giantism in children
Acromegaly in adult
Hormonal abnormalities that are controlled by GH include
- Pituitary dwarf
- Pan hypopituitary dwarf (will not pass puberty, do not develop adult sexual function, diminished mental function
- Hypothyroid (short stocky limbs, diminished mental function
- Hypo Cortisol: extremely low cortisol levels
Why is posterior pituitary not a true endocrine gland?
It is unable to synthesize hormones. It does store hormones that are produced by the hypothalamus - if there was no posterior pituitary the hypothalamus would produce a smaller amount of hormones to be released so it did not run out of it
What is the function of releasing inhibitory hormones?
Control secretion of the anterior pituitary hormones.
What are the major hypothalamic relating and inhibitory hormones?
Thyrotropin-releasing hormone (TRH) Corticotropin-releasing hormone (CRH) Growth hormone Gonadotropin-releasing hormone (GnRH) Prolactin inhibitory hormone (PIH)
Function of Thyrotropin-releasing hormone (TRH)
causes release of thyroid-stimulating hormone
Function of Corticotropin-releasing hormone (CRH)
causes release of adrenocorticotropin
Function of Growth hormone–releasing hormone (GHRH
- which causes release of growth hormone, and growth hormone inhibitory hormone (GHIH) called somatostatin, which inhibits release of growth hormone
Function of Gonadotropin-releasing hormone (GnRH)-
which causes release of the two gonadotropic hormones, luteinizing hormone and follicle-stimulating hormone
Function of Prolactin inhibitory hormone (PIH)-
which causes inhibition of prolactin secretion