Endocrinology

What kind of biomolecules are hormones?

Amino acids

Are hormones lipo/ hydrophillic?

Hydrophillic usually

What do adrenal hormones have in common with sex hormones?

Cholesterol derived

What does NA on beta adrenoreceptors do in the brionchile?

Diliation

What does NA on alpha adrenoreceptors do in the heart?

Cause contriction

What are humoral signals?

In blood

What 2 things can G proteins activate?

Adenyl cyclase

Phospholipase C

What does acetyl cyclase do?

ATP → cAMP

What does cAMP do?

Activate kinases

Do alpha or beta adrenoreceptors work through adenyl cyclase?

Beta→ adenyl cyclase

Alpha→ Phospholipase C

What does the activated phospholipase C do?

forms diacylglyercol (DAG) and IP3

inositol triphosphate

What does IP3 do?

opens Ca++ channels in Endoplasmic reticulum

What does Ca++ do?

Binds to calmodulin

what does the Ca++ - calmodulin cpmplex do?

Activate protein kinases

How does the tyrosine kinase 2nd messenger system work?

Receptor at the surface

Binding of Insulin

causes phosphorylation of the receptor= more phosphates

ADP→ ATP

\
That ATP phosphorylates a signal molecule (and that signals to do an effect)

Where are hormones deactivated?

Liver / kidney

What’s synergy?

2 hormone w/ same effect amplify the effect on the organ when working together

What’s a permissive responds?

Enhances the receptors response to a second hormone

Do sex hormones have a 2nd messenger system?

No!

What is the pituitary controlled by?

Hypothalamus

What’s the infundibulum?

Connect pituitary to hypothalamus

What’s the neurohypophysis?

Posterior pituitary

Whats the adenohypophyisis?

Anterior pituitary

What does the posterior pituitary do?

Secrete hormones

Does the pituitary just secrete?

Nope

Also neural tissue

Also storage

What is the anterior pituitary made of?

Gland tissue

Where does the anterior pituitary secrete to?

Blood

Does the anterior pituitary make hormones?

Yes

How is the release of hormones from the pituitary controlled?

Hypothalmic control or negative feednack from target tissue

Whic part of the brain acesses systemic blood?

Hypothalamus

What kind of messages does the neurohypophysis receive?

Neuroendocrine messages

What’s the hypothalamo-hypohyseal portal system?

Anterior pituitary releases hormones from the hypothalamus

What are tropic hormones?

Regulate the release of other hormones

How does the GH work?

Growth hormone works by using more fat for growth fuel

How is Growth hormone regulated?

Growth hormone releasing hormone

Growth hormone inhibiting hormone

What does the follicle stimulating hormone do?

Stimulate egg/ sperm production

What does LH do?

Production of reproductive hormones

What are the two primary posterior pituitary hormones?

Oxytocin

ADH

What does Oxytocin do at birth?

Stim uterine contraction

What is the release of oxycytocin stim by?

stretch of uterine wall

Is milk release positive/ negative feedback?

Positive

What does oxytocin bind to?

Prostaglandis (uterine contractions)

What does ADH do?

Imhibit urine production

Where are osmoreceptors?

In the blood tasting part of the brain (hypothalamus)

Is ADH inhibited or stim @ low blood pressure?

ADH released @ low bp

What inhibits ADH release?

Alcohol

Diuretics

What’s diabetes insipidus characterised by?

* tasteless

What’s diabetes mellitus?

Glucose in urine

What will ADH deficiency cause?

Diabetes insipidus

What happens to GnRH after made in hypothalamus?

Sent to pituitary

How does the pituitary respond to GnRH?

releases gonadotropins

What are the gonadotropins>

LH

FSH

\

What does oestrogen do to GnRH?

inhibit


1. the secretion of it


1. pituitary responding to it

What does the thyroid gland produce?

Thyroxine→ T4

Triidothyronine→ T3

What kind of hormones are T3 and T4?

metabolic hormones

What does T3 and T4 determine?

Basal metabolic rate

What does the thyroid produce?

Calcitonin

What does calcitonin do?

Regulates Ca++ levels

How is iodine gathered in the thyroid?

In the follicles

What does iodine combine with?

Tyrosine

Where does iodine combine with tyrosine to produce thyroxine and triidothyronine>?

in the colloid

What are the follicles?

Each follicle consists of follicular cells surrounding the fluid known as colloid

When is T4 and T3 released into the blood?

Upon TSH stimulation

Kind kind of ducts are in the tyroid?

None! trick question bitch

What are colloids surrounded by?

Capillaries

Is the release of T3 and T4 endo/ exocrine?>

Endoctrine

upon TSH stimulation its released into the capillaries that surround the colloids

What’s thyroid hormone composed of?

thyroxine and triidothyronine

Which is the active form ?

T3 / T4

T3= ACTIVE

What’s secreted more?

T4 or T3

T4 secreted mostly

What activates T3?

Cell membrane of target tissue

Which tissues do not require thyroid hormone?

Brain/ testes/ uterus/ thyroid

=> diff metabolic pathways

What does thyroid hormone stimulate?

Breakdown of glucose

What is the secretion of TH controlled by ?

TSH

thyroid stimulating hormone

What happens to heat wheh thyroid hormone takes effect?

Produced as glucose broken down

When is thyroid hormone released?

When


1. cold


1. pregant

What can an underactive thyroid be caused by?

Low iodine (taken up by follicle cells and relesed into the colloid)

low iodine= no T3 and T4 activation

\

What happens due to an underactive thyroid?

1. goiter

Why does a goiter form?

T4 and T3 dont form therefore no negataive feedback to stop ‘

'TSH release therefore a build up!

What does hypothyroidism cause in kids?

Cretinism

What are the symptoms of hypothyroism?

Cold

Fat

Constipated

Tired

What’s grave’s disease?

hyperthyroidism

What does calcitomin do?

Lower Ca++ levels in blood

How does calcitonin work>?

Prevents release of Ca from bones

More Ca into bones

Ca released @ kidneys

Where’s the parathyroid?

In the thyroid

How many parathyroids?

4

What does the paraathyroid do?

Secrete parathyroid hormone

What does the parthyroid hormone do?/

Increase Ca levels in blood

What happens to PTH levels at hypercalcaemia?

Decreased PTH

Increased Calcitonin

Where does Ca come from if PTH active?

bone matrix

more absorbed in intestine

less absorbed in kidney

What does PTH does to Vit D?>

Activates as Vit D needed to absorb Ca

What controls PTH?

Calcium levels

What happes at hyperparathyrodism

A lot of Ca released from bones

Muscle weaknes

Kidney stones as less Ca excreted

What can hypoparathyroids do?

Muscle twitches and diaphargm disfucntion

What cells are responsible for the exocrine pancreas?

Acinar cells produce enzymes

What are islets of langerhans surrounded by?

Acinar cells

What are the hormone producing cells?

Alpha

Beta

What do alpha cells do?

Produce Glucagon

(sounds like an alpha terraria boss)

What do beta cells do?

Produce Insulin

What is glucagon production stimulated by?

Low blood sugar

What gluconeogenesis?

Production of glucose from lactic acid