[M6] Part 3.2: Adrenal Gland (medulla) Flashcards
Inner adrenal gland composed of chromaffin cells
ADRENAL MEDULLA
ADRENAL MEDULLA Inner adrenal gland composed of chromaffin cells that secretes the hormone, _____
catecholamines
For adrenal medulla to secrete/produce
catecholamine, it require its ____
precursors
What are the two precursors of adrenal medulla
→ Phenylalanine
→ Tyrosine
Phenylalanine and Tyrosine are ___
amino acids
Catecholamines are named catecholamines
because of its ____
structure
What is/are present in Catecholamine structure?
Catechol nucleus;
Amine side chain
benzene with 2 hydroxyl side group
Catechol nucleus
Catechol nucleus is a ___ with ___ hydroxyl
side group
benzene ;
2
Chromaffin cells are derived from ____
neural crest
neural crest is specifically known as:
primordial neural crest (PNC)
Refers to the group of hormones synthesized by
chromaffin cells of the adrenal medulla
CATECHOLAMINES
What are the 3 common catecholamines
Epinephrine, Norepinephrine, and
Dopamine
What are the functions of CATECHOLAMINES
● 1st responder to stress
● Promotes fight-or-flight response
● Dilate pupils
One of the functions of catecholamine is that it Promotes fight-or-flight response because catecholamines:
→ ____ (Inc/dec) ____ output and ____
→ Diverts ____ toward ___ and ____
→ Mobilizes ___ from ___ (releasing ___)
→ Increases ; cardiac ; blood pressure
→ blood ; muscle ; brain
→ fuel ; storage ; glucose
DEVELOPMENT OF MEDULLA:
- At the early stage of ____ , ___ will go to
____ region
gestation ;
Primordial Neural Crest (PNC);
thoracic
DEVELOPMENT OF MEDULLA:
- A few weeks after, majority of ___ will migrate to
____ to form ___
PNC ;
Adrenal cortex ;
Adrenal Medulla
What are the 2 cells that arises from the neural crest?
Sympathogonia
Pheochromoblast
sympathetic ganglion cells
Sympathogonia
Type of tumor that may arise in Sympathogonia
Sympathoblasts
childhood tumor
Sympathoblasts
rarely seen among adolescence
Sympathogonia
Type of tumor that arises from ganglion cells
Sympathoblasts
Sympathoblasts secretes _____
Homovanillic Acid (HVA)
Examples of Sympathoblasts
Malignant neuroblastoma
Benign ganglioneuroma
medulla chromaffin cells
Pheochromoblast
seen in adrenal medulla
Pheochromoblast
Type of tumor that may arise in Pheochromoblast
Pheochromocytoma
Pheochromocytoma secretes?
catecholamines
Type of tumor that arises from chromaffin cells
Pheochromocytoma
Pheochromocytoma Has the ability to migrate towards ____, forming _____
AORTA ;
paraganglia
BIOSYNTHESIS OF CATECHOLAMINES
- In cytoplasm
● To synthesize catecholamine, ____ (_____, specifically, ____)
are required
precursors;
phenylalanine and tyrosine ;
tyrosine
Phenylalanine should be converted to _____
tyrosine
immediate/ direct precursor
Tyrosine
T/F: Tyrosine is an immediate/ direct precursor meaning it will
not be converted anymore
T
● Conversion of phenylalanine to ___ to ___ to ___ occurs in the ___
tyrosine
DOPA ;
Dopamine ;
cytoplasm
BIOSYNTHESIS OF CATECHOLAMINES
- In cytoplasm
Once dopamine is synthesized, it will be transported
into a ___ via a transporter called as ____
lipid vesicle ;
VMAT (Vesicular Monoamine Transporter)
BIOSYNTHESIS OF CATECHOLAMINES
- In the lipid vesicle
● ____ inside the lipid vesicle will be converted to ____
● ____ will be released out of the lipid
vesicle, going to the ___
Dopamine ; Norepinephrine (NE)
Norepinephrine ; cytoplasm
BIOSYNTHESIS OF CATECHOLAMINES
- In cytoplasm
● Norepinephrine in the cytoplasm will be converted to
____ by the enzyme _____
● The synthesized/converted ____ will be
____ into a _____ by ____
● Epinephrine (EPI) ; PNMT (Phenylethanolamine N-methyltransferase)
● Epinephrine ; transported ; secretory vesicle ; VMAT
PNMT - is _____ dependent
cortisol
BIOSYNTHESIS OF CATECHOLAMINES
- In the secretory vesicle
● ____inside the secretory vesicle will be
released from the cell through the process called
_____
Epinephrine ;
exocytosis
secretory vesicle attaches to the
cell membrane and will form vacuole to release
the content outside the cell
Exocytosis
BIOSYNTHESIS OF CATECHOLAMINES
- In the circulation
● ____ of ___ will be bound to ____
50%
epinephrine
protein
When will Adrenal Medulla release synthesized
epinephrine?
● Synthesized Epinephrine will be released if there is
a stimulation
T/F: Without stimulation Synthesized Epinephrine will STILL be released
F; it will not be released
Too much epinephrine in the body will result in
___ and ____
tachycardia
high blood pressure
Without ____, catecholamine will be
metabolized in the cytoplasm by the enzyme
_____
nerve stimulation;
catechol-O-methyltransferase
Epinephrine will be metabolized to ___
Metanephrines
Norepinephrine will be metabolized to ___
Normetanephrines
Dopamine will be metabolized to ___
Methoxytyramine
The metabolized catecholamines can be oxidized to ____ by the enzyme ____
Vanillylmandelic Acid (VMA) ; monoamine oxidase
T/F: Once catecholamine become metabolites, it can now
be discarded
T