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Flashcards in Section 3 Deck (153)
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1

Another name for hypophysis

pituitary gland

2

before pituitary was considered a master gland, now it is known that is controlled by hypothalamus, hence what is the system name

hypothalamo-pituitary axis

3

Weight of the pituitary gland, size, and when in increase by 30%

Weight of the pituitary is 0.5-1.0 g (1 cm diameter about size of a pea) – increases in size (>30 %) during pregnancy

4

where pituitary gland is found

under hypothalamus and optic chiasma

5

draw the structure of hypothalamus-pituitary gland

3 parts of anterior, 2 parts of posterior, connection between hypothalamus and pituitary gland and what is find beneath pituitary and where is optic chiasa in all this

6

pituitary found in what ventricle 

3rd ventricle

7

Hypothalamo-hypophyseal tract is derived from

8

How hypothalamus is organized

Into discrete nuclei

9

The interrelation between the hypothalamus and the anterior pituitary

- anterior pituitary is highly vascularized: capillary bed in anterior pituitary is connected to capillary bed in median eminence through portal veins
- Releasing factors are secreted into median eminence that go to pituitary
- Retrograde flow of blood allows for –ve feedback from pit. to hypothalamus

10

Synthesis , transport and release of hormones of the posterior pituitary 

11

What is halasz knife

Originally used to selectively destroy areas of brain to observe function of nuclei

12

3 types of hypothalamus neurons

13

To what types of neurons cells interacting with pituitary are classified

Somatostatin -growth inhibiting hormone

14

Hypothalamus receives signals from

-the external environment (e.g., light, nociception,
temperature, odorants) and
-internal environment (e.g., blood pressure, blood
osmolality, blood glucose and hormone levels)

15

where does hypothalamus sends integrated signals from outside and inside

-anterior pituitary gland, posterior pituitary gland,
cerebral cortex, premotor and motor neurons in the
brainstem and spinal cord, and parasympathetic and
sympathetic preganglionic neurons

16

What are circumventricular organs , the place

in 3 rd and 4th ventricle 

Circumventricular organs (CVOs) are structures in the brain characterized by their extensive and highly permeable capillaries, unlike those in the rest of the brain where there exists a blood–brain barrier (BBB) at the capillary level

-Exposed to hormones, metabolites and toxins
Example: OVLT neurons have estrogen
receptors

 

17

Name 5 CVOs

-organum vasculosum of the lamina
terminalis (OVLT)
-Subfornical organ (SFO)
-Median eminence (ME)
-Subcommissural organ (SCO)
-Area postrema (AP)

18

2 types of hypothalamic nuclei 

Supraoptic and paraventricular nuclei 

Hypothalamic-hypophysiotropic nuclei

19

Characterize supraoptic and paraventricular nuclei 

- Named after the location of the cell bodies of the neurons
-Large neurons (120-200 nm diameter)
-Neuron are specific, producing mainly oxytocin or vasopressin
- The hormone granules are visible and can be observed
traveling down the axons (8 mm/h)

20

Characterization of hypothalamic-hypophysiotropic nuclei (PeVH, PVH, Arc)

21

What can regulate hypothalamus

22

Cell types in anterior pituitary, their population, product and tarfet organ

They all have a lot ER, because they produce peptide hormones

23

name basophils and acidophils in anterior pituitary

Basophils: (take up bases readily)

Thyrotropes →TSH
Gonadotropes → LH or FSH
Corticotropes→ACTH


Acidophils:
Somatotropes →GH
Lactotropes→ PRL

24

Hypothalamic hormones controlling anterior pituitary ( structure, major functions)

25

Mechanism of action of hypothalamic hormones affecting the anterior pituitary: half life, feedback, binding , thorugh what receptor they inteact

26

How hypothalamic hormones are released (time)

vReleased is pulsatile. Pulsatility is important (e.g. treatment
of infertility with GnRH requires administration in pulses
with a defined frequency

27

Pineal gland, circadian rhythms, day-night cycles, SCN relationship

SCN can regulate itself the secretion of melatonin

28

Melatonin is sythesized from

Melatonin

29

When melatonin hits its peak and when it is secreted

at midnight ,during darkness

30

How melatonin can influence our body and where it is secreted

In pineal gland

-Neural connection with special receptors in the retina.
Other receptors present in the body
-May entrain body’s biological rhythms to the dark-light
cycle eg. Core body temperature


Other functions:
-Induction of sleep
-Depression of reproductive activity, inhibition of ovulation and
semen production in some animals –questionable role in humans
-Seasonal fluctuations may affect the timing of breeding,
migration and hibernation in mammals