Chapter 4: Organization of the mammalian hypothalamus- pituitary axes
Fill in the blanks for what hormone influences another or is influenced by: Tropic hormone <- Primary hypothalamic hormone TSH <- + TRH FSH <- + GnRH LH <- + GnRH ACTH <- __ _________ PRL <- - Dopamine GH <- - SST; + GHRH MSH <- - Dopamine
+ CRH
Fill in the blanks for what hormone influences another or is influenced by: Tropic hormone <- Primary hypothalamic hormone TSH <- + TRH FSH <- __ __________ LH <- + GnRH ACTH <- + CRH PRL <- - Dopamine GH <- - SST; + GHRH MSH <- - Dopamine
+ GnRH
Fill in the blanks for what hormone influences another or is influenced by: Tropic hormone <- Primary hypothalamic hormone TSH <- _____ _________ FSH <- + GnRH LH <- + GnRH ACTH <- + CRH PRL <- - Dopamine GH <- - SST; + GHRH MSH <- - Dopamine
+ TRH
Fill in the blanks for what hormone influences another or is influenced by: Tropic hormone <- Primary hypothalamic hormone TSH <- + TRH FSH <- + GnRH LH <- + GnRH ACTH <- + CRH PRL <- ___ ____________ GH <- - SST; + GHRH MSH <- - Dopamine
- Dopamine
Corticotrophs can secrete corticotrophin or _________
ACTH
Vasopressin (AVP) and CRH stimulate what hormone? Give letters
ACTH
Tropic hormones of the adenohypophysis are separable into three categories. Category 3 (small peptide) hormones include what four hormones?
ACTH MSH LPH endorphins
GPCR =
G protein coupled receptor
More Ghrelin -> More GHRH -> More cAMP -> More ___
GH
SST is a strong inhibitor of what hormone's release? Give letters
GH
Upon ligand binding, what structures catalyze the activation of intracellular G-proteins by stimulating the conversion of GDP to GTP?
GPCRs
What is the hormone released from the hypothalamus whose levels impact the secretion of GH? Give full name
Ghrelin
Tropic hormones of the adenohypophysis are separable into three categories. Category 2 (large) hormones include what two hormones?
PRL GH
Less Ghrelin -> more ______ -> Less GH.
SST
_____ appears to work through a GPCR linked to a GTP dependent G-protein that prevents the elevation of cAMP necessary to provoke GH release.
SST
Excessive GH secretion results in what condition?
acromegaly
Anterior pituitary aka...
adenohypophysis
The ___________________ contains five types of endocrine cell, and they are defined by the hormones they secrete: somatotropes (GH); Lactotropes (PRL); gonadotropes (LH and FSH); corticotropes (ACTH) and thyrotropes (TSH).[6]
adenohypophysis
Tropic hormones are released by what part of the pituitary? ______________________
adenohypophysis
ACTH stands for what?
adrenocorticotropic hormone
ACTH is a hormone made by the anterior or posterior pituitary gland. ACTH controls the production of cortisol.
anterior
Corticotrophs are in the anterior or posterior pituitary?
anterior
Is the adenohypophysis the anterior or posterior lobe of the pituitary gland?
anterior
List the two functions/qualities of vasopressin: 1. ____________ 2. _____________ ___
antidiuretic increases BP
Vasopressin binds to the V2 receptor to activate cAMP. This causes phosphorylation of what membrane proteins?
aquaporins
AVP =
arginine vasopressin
What second messenger needs to increase to provoke GH release?
cAMP
Phosphorylation of aquaporins causes them to interact with the luminal cell surface and allow water to enter the ____________ ________ cell.
collectin duct
ACTH (adrenocorticotropic hormone) is also known as what?
corticotropin
CRH =
corticotropin releasing hormone
ACTH controls the release of what hormone?
cortisol
Secretion of ACTH stimulates synthesis and release of ___________________
cortisol
The hypothalamus is what part of the brain? Choose one: diencephalon mesencephalon metencephalon myelencephalon telencephalon
diencephalon
What is the prolactin release-inhibiting hormone?
dopamine
Telencephalon and diencephalon become what region of the brain?
forebrain
The adenohypophysis is glandular or neuronal?
glandular
Tropic hormones of the adenohypophysis are separable into three categories. Category 1 includes what type of hormones? _________________ hormones
glycoprotein
GnRH =
gonadotropin releasing hormone
Corticotrophs are stimulated by CRH. CRH is released by what structure?
hypothalamus
Does the hypothalamus or pituitary secrete releasing and release-inhibiting hormones (RHs and RIHs)?
hypothalamus
One of the most important functions of the ________________ is to link the nervous system to the endocrine system via the pituitary gland.
hypothalamus
The pituitary is controlled by what structure?
hypothalamus
Vasopressin and oxytocin are primarily produced by the ____________________
hypothalamus
What structure releases CRH?
hypothalamus
What part of the neurohypophysis stores RHs and RIHs (releasing and release-inhibiting hormones) that are secreted from the hypothalamus? Pick one of the bolded terms. Pituitary: - Neurohypophysis * Pars nervosa * Median eminence - Adenohypophysis * Pars intermedia * Pars distalis
median eminence
Posterior pituitary aka...
neurohypophysis
The neurohypophysis is glandular or neuronal?
neuronal
Vasopressin and oxytocin are part of what group of hormones?
nonapeptide hormones
In the hypothalamus, there are neurons. The cell bodies of the neurons that produce these neurohormones are not evenly distributed throughout the hypothalamus. Instead, they are grouped together in paired clusters of cell bodies known as _____________.
nuclei
Two hormones are made in the hypothalamus and stored in the pars nervosa of the neurohypophysis: ____________ and _______________. (Since the neurohypophysis doesn't produce its own hormones, these are hormones from the hypothalamus that the neurohypophysis stores)
oxytocin vasopressin
List the two major parts of the adenohypophysis.
pars distalis pars intermedia
The pars nervosa or median eminence stores oxytocin and vasopressin? Pituitary: - Neurohypophysis * Pars nervosa * Median eminence - Adenohypophysis * Pars intermedia * Pars distalis
pars nervosa
What part of the neurohypophysis stores OXY and AVP that are secreted from the hypothalamus? Pick one of the bolded terms. Pituitary: - Neurohypophysis * Pars nervosa * Median eminence - Adenohypophysis * Pars intermedia * Pars distalis
pars nervosa
What are the two parts of the neurohypophysis?
pars nervosa median eminence
The hypothalamus releases hormones targeted at what gland?
pituitary
Is the neurohypophysis the anterior or posterior lobe of the pituitary gland??
posterior
The anterior or posterior lobe of the pituitary gland is not capable of producing its own hormones; instead, it stores hypothalamic hormones for later release into the systemic circulation.
posterior
Dopamine is an inhibitor of _________________ and ___________
prolactin melanotropin
GH release-inhibiting hormone is also known as what? Give full name
somatostatin
SST =
somatostatin
Four of the most prominent nuclei are two called ___________ nuclei and two others called the paraventricular nuclei
supraoptic
Neurosecretory neurons in the hypothalamus secrete hormones that travel to the pituitary gland where they regulate secretion of what type of hormones? _____________ hormones
tropic
The adenohypophysis releases what type of hormones? _____________ hormones
tropic
____________ hormones are hormones of the anterior lobe of the pituitary. These hormones affect growth, function, or nutrition of other endocrine cells.
tropic
List the two nonapeptides. Give full names
vasopressin oxytocin
What is the hormone that stimulates prolactin release? Give letters
TRH
Tropic hormones of the adenohypophysis are separable into three categories. Category 1 (glycoprotein) hormones include what three hormones?
TSH FSH LH
TRH =
Thyrotropin releasing hormone