week 3- L1-pituitary gland

Question 1

hormones definition

Answer 1

messenger carried from the organ produced to organ they affect by blood stream

Question 2

main types of hormones

Answer 2

peptides and steroids

Question 3

difference between peptides and steroids

Answer 3

synthesis- peptides as pro-hormones and steroid as cholesterol precursors
storage- peptides stored in vesicles (regulatory) and steroids released immediately (constitutive)
receptors-found on the cell membrane and use 2ndary messenger while steroid use intracellular receptors to change genes expression

Question 4

what structures are above and below pituitary gland?

Answer 4

above-optic chiasm

below-sella turcica of sphenoid bone

Question 5

what regulates the anterior pituitary gland?

Answer 5

parvocellular neurons

Question 6

how parvocellular neurons function?

Answer 6

short and terminate in the median eminence where hypothalamic stimulating/ inhibitory factors are released into capillary plexus
regulatory factors carried by portal circulation

Question 7

anterior pituitary gland contains

Answer 7

glands aka glandular

Question 8

types of endocrine cells in pituitary gland

Answer 8

somatotrophs, lactotroph, corticotrophs, thyrotrophs, gonadotrophs

Question 9

pituitary gland aka

Answer 9

adenohypophysis

Question 10

hypothalamic releasing/inhibitory factors regulated via

Answer 10

hypophyseal-pituitary portal system

Question 11

chain of events to stimulate hormone release in pituitary gland

Answer 11

axons of neuro-secretory cells release hormones into hypothalamo-pituitary portal system
travel via portal system
release hormone from pituitary gland
hormone leave via blood
NB: blood vessel constitute hypothalamo-pituitary portal system

Question 12

types hormones released at hypothalamus and pituitary gland

Answer 12

hypothalamus- releasing hormone (RH)

pituitary gland- stimulating hormone (SH) aka trophin

Question 13

anterior pituitary gland cell and their hormones

Answer 13

somatotropin-growth
lactotroph- prolactin
thyrotroph- thyroid stimulating hormone
gonadotrophs- luteinising hormone and follicle stimulating hormone
corticotrophs- adrenocorticotrophic hormone (ACTH)

Question 14

hypothalami-pituitary regulation

Answer 14

growth hormone releasing hormone+somatostatin
dopamine-inhib
thyrotrophin releasing hormone
gonadotrophin releasing hormone
corticotrophin releasing hormone

Question 15

anterior pituitary hormone and their target cells

Answer 15

growth-general body tissues (liver )
prolactin- lactating breast in women
thyrotrophin-thyroid gland
gonadotrophin- testis man and ovary woman
corticotrophin-adrenal gland

Question 16

pituitary tumour can cause

Answer 16

squashing of optic chiasm

Question 17

visual fields of pituitary gland tumour

Answer 17

temporal part of visual field is loss- loss of peripheral vision aka bitemporal hemianopia

Question 18

constituent of visual vision

Answer 18

nasal and temporal part of visual perimetry

Question 19

bitemporal hemianopia

Answer 19

loss half of the visual field, the temporal field specifically
compression of optic chiasm prevent transmission of sensory information from lateral visual fields to occipital lobe. fibres from nasal retinae cross at optic chiasm

Question 20

neuroendocrine reflex arc milk production

Answer 20

mechanical nipple stimulation to afferent pathway
afferent signal inhibition’s dopamine from dopaminergic neurons
less dopamine in hypothalamic-pituitary portal system=less inhibition of anterior pituitary lactotroph
increase plasma prolactin -increase milk secretion in mammalian gland

Question 21

growth hormone action mechanism

Answer 21

growth hormone somatotrophin 1-directly binds to body tissues receptors or 2-indirectly binds to receptor on liver causing IGF1(adults) and IGF2 (foetal) release from liver and binds to skeleton

Question 22

pituitary disorders concerning growth hormones

Answer 22

gigantism and acromegaly

Question 23

signs and symptoms of acromegaly

Answer 23

coarsening of facial features 
macroglossia
prominent nose
large jaws-prognathism
increased hand and feet size
sweatiness
headache

Question 24

posterior pituitary gland aka

Answer 24

neurohypophysis

Question 25

hormones concerned with posterior pituitary gland

Answer 25

arginine vasopressin-AVP aka anti diuretic hormone

oxytocin

Question 26

anatomical relationship with hypothalamus APG

Answer 26

anatomically distinct

Question 27

anatomical relationship with hypothalamus PPG

Answer 27

anatomically continuous

Question 28

what hypothalamic cells regulates PPG

Answer 28

hypothalamic magnocellular neurons

Question 29

hypothalamic magnocellular neurons originates

Answer 29

supraoptic-AVP and paraventricular-oxytocin hypothalamic nuclei

Question 30

PPG chain of command stimulation

Answer 30

nuclei->stalk->posterior pituitary-> diffusion of hormone into blood capillaries and leave via blood

Question 31

AVP aka anti-diuretic hormone function

Answer 31

stimulates water reabsorption in renal collecting duct to concentrate urine

Question 32

vasopressin mechanism

Answer 32

binding AVP to V2 receptor, signalling cascade to cause aquaporin 2 to fuse with cell membrane. water reabsorption to plasma through aquaporin 3

Question 33

action of oxytocin

Answer 33

1-uterus at parturition-myoemetrial cells-contraction-delivery baby
2-breasting lactation-myoepithelial cells-contraction-milk ejection

Question 34

milk ejection mechanism

Answer 34

mechanical stimulation of afferent pathway
signal integration in hypothalamus and oxytocin release stimulation
AP down oxytocin neutron and secretion into blood stream
increased plasma oxytocin increase milk ejection