PHYSIOLOGY - Neuroendocrinology

Question 1

What is the neuroendocrine system?

Answer 1

Interaction between the nervous system and the endocrine system

Question 2

What are the two main anatomical components of the neuroendocrine system?

Answer 2

Hypothalamus
Pituitary gland

Question 3

What are the three functions of the hypothalamus within the neuroendocrine system?

Answer 3

1. Exerts autonomic nervous system control on hormone release by the adrenal medulla
2. Produces and releases regulatory and inhibitory hormones
3. Produces antidiuretic hormone (ADH) and oxytocin

Question 4

How is the hypothalamus a heterogeneous organ?

Answer 4

The hypothalamus is a heterogenous organ as it is made up of many different nuclei (clusters of neuronal cell bodies)

Question 5

Which type of neurones produce oxytocin and antidiuretic hormone (ADH)?

Answer 5

Magnocellular neurones

Question 6

In which nucleus in the hypothalamus is oxytocin produced?

Answer 6

Paraventricular nucleus

Question 7

In which nucleus in the hypothalamus is antidiuretic hormone (ADH) produced?

Answer 7

Supraoptic nucleus

Question 8

Which five regulatory/inhibitory hormones are produced by the hypothalamus?

Answer 8

Gonadotrophin releasing hormone (GnRH)
Corticotrophin releasing hormone (CRH)
Thyrotrophin releasing hormone (TRH)
Dopamine
Somatostatin

Question 9

What is the sella turcica?

Answer 9

Depression in the sphenoid bone that contains the pituitary gland

Question 10

What are the two structural components of the pituitary gland?

Answer 10

Anterior pituitary gland
Posterior pituitary gland

Question 11

What is the embryological origin of the anterior pituitary gland?

Answer 11

Ectoderm

Question 12

What is the embryological origin of the posterior pituitary gland?

Answer 12

Neuroectoderm

Question 13

What is the section of tissue residing between the anterior and posterior pituitary gland?

Answer 13

Pars intermedia

Question 14

Which hormone is secreted by the pars intermedia?

Answer 14

Melanocyte stimulating hormone

Question 15

What is the function of the anterior pituitary gland?

Answer 15

Production and release of tropic hormones and direct action hormones

Question 16

What is the difference between tropic hormones and direct acting hormones?

Answer 16

Tropic hormones stimulate other endocrine glands to facilitate the realise of another hormone whereas direct acting hormones act directly on the target organ

Question 17

What regulates the release of tropic and direct acting hormones from the anterior pituitary gland?

Answer 17

Hypothalamus releases regulatory and inhibitory hormones into the hypophyseal portal system which transports these hormones to the anterior pituitary gland where they will regulate the release of tropic and direct acting hormones

Question 18

What are the two main types of chromophil secretary cells found in the anterior pituitary gland?

Answer 18

Acidophils
Basophils

Question 19

What are the two subdivisions of acidophils?

Answer 19

Somatotrophs
Mammotrophs

Question 20

Which hormone is produced by somatotrophs in the anterior pituitary gland?

Answer 20

Growth hormone

Question 21

Which hormone is produced by mammotrophs in the anterior pituitary gland?

Answer 21

Prolactin

Question 22

What are the three subdivisions of basophils?

Answer 22

Gonadotrophs
Thyrotrophs
Corticotrophs

Question 23

Which hormones are produced by gonadotrophs in the anterior pituitary gland?

Answer 23

Follicular stimulating hormone (FSH)
Leutinising hormone (LH)

Question 24

Which hormone is produced by thyrotrophs in the anterior pituitary gland?

Answer 24

Thyroid stimulating hormone (TSH)

Question 25

Which hormone is produced by corticotrophs in the anterior pituitary gland?

Answer 25

Adrenocorticotropic hormone (ACTH)

Question 26

What are chromophobes?

Answer 26

Chromophils which have released their hormones

Question 27

What is the function of the posterior pituitary gland?

Answer 27

Storage and release of oxytocin and antidiuretic hormone (ADH) that has been produced by the hypothalamus

Question 28

What is the main histological component of the posterior pituitary gland?

Answer 28

Non-myelinated axons

Question 29

What are the supporting cells within the posterior pituitary gland?

Answer 29

Pituicytes

Question 30

What are herring bodies?

Answer 30

Herring bodies are dilated axon terminals in the posterior pituitary gland that store and release oxytocin and antidiuretic hormone (ADH)

Question 31

What does the pineal gland secrete?

Answer 31

Melatonin

Question 32

What are the two main cell types seen in the pineal gland?

Answer 32

Pinealocytes Astrocytes

Question 33

What is pineal sand?

Answer 33

Concentric layers of calcium and magnesium phosphate seen in ageing pineal glands

Question 34

Describe the histological appearance of the thyroid gland

Answer 34

The thyroid gland has a fibrous outer capsule from which fine septa extend to seperate the thyroid gland into lobules. These lobules contain thyroid follicles filled with colloid (thyroid hormone precursor) and surrounded by a single layer of cuboidal epithelium