Semester 2: L7: Hormones 1 Flashcards
what are the 4 types of hormones?
Prostaglandins
Pheromones
Peptide hormones
Steroid hormones
is the hypothalamus a gland?
no
what doe stem hypothalamus do?
controls glands
Where are the adrenal glands located?
above the kidneys
Where is the thyroid gland located?
straddles the trachea
where are the parathyroids glands located?
They are embedded in the back of the thyroid gland
How many parathyroids glands do we have?
4
what are Prostaglandins also known as?
local hormones
what type of hormone is adrenaline?
catecholamines
How does adrenaline work?
- Released into blood from adrenal glands
- Travels to target organ (liver)
- binds to receptors on the surface of target cells, causing a cascade of reactions involving enzymes
- Leads to the break down of glycogen to release glucose
Are peptide hormones slow or fast acting?
fast acting
what are slow acting hormones?
steroid hormones
why are peptide hormones fast acting?
they don’t have to synthesis new proteins
Name two types of steroid hormones?
Cortisol
Aldosterone
How do steroid hormones work?
- carried to target cell
- diffuse in through cell membrane
- Binds to receptors in nucleus.
- Here transcription and translation takes place to create new proteins.
- BACK
are steroid hormones soluble in blood?
They are not soluble in blood. Require carrier protein or equivalent.
Does thyroid hormone work similarly to a steroid hormone?
yes
What controls blood glucose?
Insulin and glucagon
What are the responsive hormones?
adrenalin - danger
cortisol - starvation
thyroxine - metabolic rate
Where is adrenaline produced?
in the medulla
Medulla produces…
catecholamines
what does the adrenal cortex produce?
steroid hormones
what does the cortex inner zone produce?
progesterone and testosterone
what does the middle zone of the cortex produce?
cortisol
what doe stem outer zone of the adrenal cortex produce?
aldosterone
what is cortisol classed as?
glucocorticoid
what is aldosterone classed as?
mineralocorticoid
what is the adrenal medulla derived from?
sympathetic nervous system
are hormones mostly produced in the anterior or posterior pituitary ?
anterior
what does adrenaline do?
raises blood glucose
increases heart rate
lowers metabolism
how does adrenaline raise blood glucose levels?
- Liver glycogenolysis
- Suppress insulin secretion
- Stimulate glucagon secretion
what receptor is found on our heart muscle?
beta 1
Noradrenalin and adrenalin do what to voluntary muscle arterioles ?
causes the voluntary muscle arterioles to dilate via the beta 2 receptor
what happens to arterioles in skin, gut when adrenaline binds to its receptor?
adrenaline binds to alpha 1 receptor causing the arterioles in skin, gut to constrict
does adrenaline cause the dialation of the bronchi, if so what receptor is used?
yes and beta 2
what are the 2 type of receptors adrenaline has?
α and β
can β receptor’s be blocked?
yes by β-blockers
what is the Hypothalamic-Pituitary-Adrenal Axis ?
controls reactions to stress and regulates many body processes
How is cortisol released?
CRh- released form hypothalamus
stimulates anterior pituitary
releasing ACTH
enters the blood, travels o the adrenal gland, stimulates adrenal cortex, which produces the hormone cortisol.
What happens once cortisol is released?
Cortisol is released into the blood, moves to the target tissue.
what happens when cortisol goes to muscle and fat cells?
at muscle and fat cells it induces gluconeogenesis.
- liver deamination of amino acids followed by gluconeogenesis
what happens when cortisol goes to the liver?
liver - deamination of amino acids followed by gluconeogenesis
what is deamination ?
Removal of amino group
what are the 3 levels of control?
Hypothalamus
-corticotrophin
releasing hormone
Anterior pituitary
- adrenocorticotrophic
hormone
Adrenal cortex
- cortisolCortisol feeds back to pituitary and hypothalamus, this is known as ?
negative feedback
what happens when you have a low blood pressure level?
LBP is detected by the kidney by specific cells, which produce renin (enzyme), renin converts Angiotensinigen to angiotensin 1 and then ACE converts this too angiotensin 2, this stimulates the adrenal cortex, producing aldosterone. This increases reabsorption of water and sodium. BP rises.
what is renin?
an enzyme
what enzyme turns Angiotensin I to Angiotensin II ?
Angiotensin converting
Enzyme (ACE)
what can Angiotensin II lead too?
Aldosterone
Vasopressin
Vasoconstriction
Bradykinin breakdown
what happens when you have high blood pressure?
?
what is Aldosteronism ?
High aldosterone levels
what does Aldosteronism
lead too?
high blood sodium which can cause hypertension
and Low blood potassium which can cause muscular paralysis
what is Addison’s Disease ?
Adrenocortical insufficiency
what are symptoms of Addison’s Disease ?
Low cortisol Mental lethargy Weight loss Low blood pressure Skin pigmentation
what is Cushing’s Syndrome?
an excess of cortisol
what are symptoms of Cushing’s Syndrome?
Fat redistribution (Moon Face)
Easy bruising
Poor wound healing
Susceptibility to infection
what is linked very closely to na increase in cortisol levels?
stress
what can too much cortisol suppress?
Suppresses immune function
check last slide
last three points
