Intro to Endocrinology

What is a gland

Organ consisting of specialized secretory cells

Can glands be unicellular

yes - uni or multi cellular

2 types of glands

Exocrine or Endocrine

Exocrine Glands

Secrete product onto an epithelial surface, directly or through ducts

Examples of exocrine glands

Gastric glands

Pancreas

Salivary glands

Endocrine Glands

Ductless Glands - Secrete Hormones

What type of gland is this

Endocrine

What type of gland is this

Exocrine gland

Give an example of an organ with more than 1 type pf gland

Pancreas

1. Pancreas

2. Splenic artery

3. Pancreatic islets

4. Spleen

5. Acinar cells

6. Pancreatic duct

7. Duodenum of small intestine

8. Common bile duct

9. Bile duct (from gal bladder)

Role of acinar cells

Secrete digestive enzymes

1. Hypothalamus

2. Pineal gland

3. Parathyroid glands

4. Heart

5. Kidney

6. Adipose tissue

7. Digestive tract

8. Pancreatic islets

9. Gonads

10. Adrenal glands

11. Thymus

12. Thyroid gland

13. Pituitary gland

Hormone definitions

The pituitary gland is also known as ____

The master gland

What does the pituitary gland control

Controls Thyroid, Adrenal Cortex, Ovary, Testes

What controls the pituitary

Hypothalamus (Hypothalamic-Pituitary Axis)

Input to hypothalamus comes from ______

CNS

Output from hypothalamus goes to ______

Pituitary

Coordination between the nervous system and the endocrine system happens in what gland

hypothalamus

What clinical diagnoses/symptoms is the pituitary gland responsible for

Anxiety

Depression

Hair loss

High BP

Irregular periods

Unexpected breast milk production

Low energy & sex drive

Stunted growth / unusual growth spurts

Unexplained weight gain

Vision changes

Where is 7?

What do 8, 9 & 10 combine to be?

1. Hypothalamus

2. Mammillary body

3. Median eminence

4. Infundibulum

5. Infundibular stalk

6. Pars nervosa

7. Hypophyseal fossa (in sella turcica of sphenoid bone)

8. Pars distalis

9. Pars intermedia

10. Pars tuberalis

11. Optic chiasm

12. Posterior pituitary

    8, 9 & 10 combine to be the anterior pituitary

What’s the name of the infolding from the roof of the mouth that becomes the anterior pituitary in embryological development

Rathke’s pouch (made of ectodermal tissue)

What makes up the posterior pituitary (& what type of tissue)

Down growth from floor of 3rd ventricle

(nervous tissue)

What kind of connection exists between the hypothalamus and the posterior pituitary

Neural connection

Where are the SOP (supraoptic nucleus) and the PVN (paraventricular nucleus) located

Hypothalamus

What do cell bodies of the SOP and PVN produce

Oxytocin & Antidiuretic hormone (ADH)

Where are the oxytocin & ADH stored & wat are they stored with

In vesicles

Oxytocin with neurophysin 1

Antidiuretic hormone with neurophysin 2

The hormones are transported directionally along ______ to the _______

Along axons to the posterior pituitary (where they are released into the blood stream)

Location & flow of hormones in hypothalamus

Blood supply to hypothalamus

Superior Hypophysial Artery

The Superior Hypophysial Artery in the hypothalamus forms a plexus called _______

Primary (Capillary) Plexus

Where does the primary (capillary) plexus form

In the median eminence

Blood vessels in the primary (capillary) plexus contain fenestrations - what are these?

Small pores that allow for the exchange of hormones & other materials

Through what system does blood exit the primary (capillary) plexus

Hypothalamo-Hypophyseal Portal System

Path of blood through the hypothalamo-hypophyseal portal system

Primary plexus → Descend via infundibulum → Second capillary plexus

Where is the Second Capillary Plexus located

Pars Distallis

Are there fenestrations in the second capillary plexus

yes

What does blood exit from the anterior pituitary through

Efferent veins

Where are each of these produced:

Follicle stimulating hormone (FSH)

Growth hormone

Thyroid stimulating hormone

Prolactin

Adrenocorticotrophic hormone

Anterior pituitary

What regulates the production & release of FSH & luteinising hormone

Gonadotrophin (releasing hormone)

Where do FSH & luteinising hormone act?

Gonads

What regulates the production & release of Growth hormone

Growth hormone releasing hormone

Growth hormone inhibitory hormone / Somatostatin

Where does growth hormone act?

All organs

What regulates the production & release of thyroid stimulating hormone

Thyrotrophin releasing hormone

Where does TSH act?

Thyroid

What regulates the production & release of Prolactin

Prolactin releasing hormone

Prolactin inhibitory hormone / Dopamine

Where does prolactin act?

Breast tissue

What regulates the production & release of Adrenocorticotrophic hormone

Corticotrophin releasing hormone

Where does Adrenocorticotrophic hormone act?

Adrenal cortex

C

B

C