Topic 9 - Endocrinology Flashcards by Ekaterina Savenya

What are the main endocrine glands?

Hypothalamus/Pituitary
Thyroid
Parathyroid
Pancreas
Adrenal
Ovaries/testicles

How well did you know this?

Not at all

Perfectly

What is the hypothalamic-pituitary axis?

A complex set of direct influences and feedback interactions among three components: the hypothalamus, the pituitary gland (a pea-shaped structure located below the thalamus), and the adrenal glands (small, conical organs on top of the kidneys).

How well did you know this?

Not at all

Perfectly

What are the two lobes of the pituitary gland?

Anterior pituitary

- Posterior pituitary

How well did you know this?

Not at all

Perfectly

What is the function of the anterior pituitary gland?

To produce various hormones

How well did you know this?

Not at all

Perfectly

What is the function of the posterior pituitary gland?

To store various hormones (produced in the hypothalamus)

How well did you know this?

Not at all

Perfectly

Which hormones does the anterior pituitary gland produce?

Growth hormone
Adrenocorticotrophic hormone (ACTH)
Gonadotrophins (FSH and LH)
Thyroid stimulating hormone or thyrotrophin (TSH)
Prolactin (PRL)

How well did you know this?

Not at all

Perfectly

What is the function of growth hormone?

Skeletal growth

How well did you know this?

Not at all

Perfectly

What is the function of ACTH?

Adrenocorticotrophic hormone stimulates the adrenals to produce steroids

How well did you know this?

Not at all

Perfectly

What is the function of gonadotrophins?

Stimulate the testicles or ovaries to produce sex hormones

How well did you know this?

Not at all

Perfectly

What is the function of TSH?

Thyroid stimulating hormone or thyrotrophin stimulates the thyroid to produce thyroid hormones

How well did you know this?

Not at all

Perfectly

What is the function of prolactin?

Stimulates breast milk production

How well did you know this?

Not at all

Perfectly

Which hormones does the posterior pituitary gland store?

Antidiuretic hormone (ADH)

- Oxytocin

How well did you know this?

Not at all

Perfectly

What is the function of ADH?

Stimulates water reabsorption by the kidneys

How well did you know this?

Not at all

Perfectly

What is the function of Oxytocin?

Helps uterine contractions during labour

How well did you know this?

Not at all

Perfectly

How is the pituitary gland controlled?

By the hypothalamus

How well did you know this?

Not at all

Perfectly

Which hormones produced in the hypothalamus control the anterior pituitary gland?

Corticotrophin releasing hormone (CRH)
Growth hormone releasing hormone (GHRH)
Thyrotropin releasing hormone (TRH)
Gonadotrophin releasing hormone (GnRH)

How well did you know this?

Not at all

Perfectly

Why is there no prolactin releasing hormone?

Prolactin is under the inhibitory effect of the hypothalamus

How well did you know this?

Not at all

Perfectly

What is the function of Corticotrophin releasing hormone?

stimulates ACTH secretion

How well did you know this?

Not at all

Perfectly

What is the function of Growth hormone releasing hormone (GHRH)?

stimulates GH secretion

How well did you know this?

Not at all

Perfectly

What is the function of Thyrotropin releasing hormone (TRH)?

stimulates TSH secretion

What is the function of Thyrotropin releasing hormone (TRH)?

stimulates TSH secretion

What is the function of Gonadotrophin releasing hormone (GnRH)?

stimulates FSH and LH secretion

Which hormones does cortisol switch off?

ACTH and CRH

Which hormones does GH switch off?

GH and GHRH

Which hormones do thyroid hormones switch off?

TSH and TRH

Which hormones do sex hormones switch off?

FSH/LH and GnRH

Which glands are not controlled by the pituitary?

- Adrenal medulla - Parathyroid - Pancreas - Gut hormones

What does the adrenal medulla produce?

adrenaline and noradrenaline

What does the parathyroid control?

Calcium levels

What does the pancreas control (as a gland)?

Sugar levels

What are the parts of the thyroid gland?

- Midline isthmus (just below the cricoid cartilage) - Right lobe - Left lobe

What is the function of thyroid C cells?

Production of calcitonin (calcium metabolism)

What controls calcium metabolism?

4 parathryoid glands sitting behind the thyroid

Which organs are involved in calcium metabolism?

- Kidneys (calcium excretion and production of active vitamin D) - Gut (Absorption of calcium) - Bone (Storage of calcium) - Thyroid

Where are the adrenal glands located?

On the kidneys

What are the adrenal glands composed of?

- Adrenal cortex (90%) | - Adrenal medulla (10%)

What does the adrenal cortex produce?

- Cortocosteroids (cortisol) - Androgens (male hormones) - Mineralocorticoid (aldosterone)

What does the adrenal medulla produce?

-Catecholamines (adrenaline, noradrenaline and dopamine)

What are the testes composed of?

- Interstitial or Leydig cells - Seminiferous tubules - Sertoli cells

What is the function of interstitial or leydig cells?

Produce testosterone

What is the function of seminiferous tubules?

Made up of germ cells producing sperms

What is the function of sertoli cells?

Help in sperm production and produce inhibin

What are the clinical abnormalities possible in various glands?

- Hormone over-secretion (primary/secondary) - Hormonal under-secretion (primary/secondary) - Tumour/nodules in the gland that don't affect hormone secretion

What are static tests used for?

-diagnosing abnormalities of thyroid and sex glands

What do the static tests for primary hyperthyroidism test for?

- Thyroid hormones (T3 and T4) - TSH - If primary hyperthyroidism is present then T3 and/or T4 is elevated with suppressed (undetectable) TSH

What are the types of tests used to detect hormonal abnormalities?

- Static tests - Stimulation tests - Suppression tests

What are stimulation tests used for?

for suspected hormonal under-secretion where a static test is NOT ENOUGH

What are suppression tests used for?

some hormonal over-secretion

What are some examples of stimulation tests?

-Giving ACTH to test for adrenal insufficiency (synacthen test) -