DEMO – II Adrenal Glands + Pituitary Gland

1. DEMO –IIAdrenal Glands + Pituitary Gland Ali JassimAlhashli Year III – Unit IV (Endocrine & Reproductive Systems)

2. STATION – 1: Embryology of AdrenalGlands • The adrenal glands consist of twoparts: • An outer cortex which has threelayers: • Zonaglomerulasa(producingmineralocorticoids). • Zonafasciculata (producingglucocorticoids). • Zonareticularis (producingandrogens). • - An inner medulla (containing chromaffin cells which are post-ganglionic sympathetic neurons. These cells are columnar in shape and stain with potassium dichromate. They secret catecholeamines: epinephrine &NE). • The development of adrenal glands with it’s twoportions: • Neural crest cells → some cells are going to descend between mesintary & urogenitalridge. • In this region, celomic mesothelium is formed during 4th – 5thwk. • Which will then become the cortex during 6th – 7thwk. • -This cortex will engulf the sympathochromaffin cells which are derived from the neural crest cells (forming themedulla). • Note: - At birth: there are only two layers of the cortex (glomerulasa &fasciculata). • At the end of the 3rd yr: zona reticularis willappear. • Pheochromocytoma: is a tumor of the adrenal medulla secreting catecholeamines and resulting inhypertension.

3. STATION – 1: Embryology of AdrenalGlands

4. STATION – 1: Embryology of AdrenalGlands

5. STATION – 1: Embryology of PituitaryGland • Embryology of the pituitary gland: • - Anterior pituitary (adenohypophysis): developing from the surface ectoderm near the mouth (from the roof of the stomodeum by forming Rathke’s pouch which if persists will result in craniopharyngioma). • - Posterior pituitary (neurohypophysis): Proencephalon→ diencephalon → posteriorpituitary • Mesencephalon. • Rhombencephalon.

6. STATION – 2: Pituitary GlandAnatomy • Pituitary gland is in the middle cranial fossa(which is formed by the sphenoid bone that is butterfly- shaped) in the sella turcica(specifically). •Pituitary stalk (infundibulum): the connection between the hypothalamus and theneurohypophysis. •Hypophyseal portal system (venous – capillaries breaking down to capillaries – no valves): releasing factors are secreted by the hypothalamus and transported to the anterior pituitary through this portal system allowing the secretion of pituitaryhormones.

7. STATION – 2: Hormones Secreted By The PituitaryGland

8. STATION – 2: Pituitary(x-ray) • Tumor in thepituitary: • Might compress optic chiasma resulting in visualdisturbances (bitemporalhemianopia) • Bursting into sphenoidbone. Thissella turcica is enlarged

9. STATION – 3: AdrenalsHistology The adrenalgland

10. STATION -3 STATION– 3:AdrenalsHistology • *Producing mineralocorticoid (aldosterone mainly) underthe influence of renin-angioten II system. • Arranged inclumps. • Pale staining because oflipids. • *Producing glucocorticoids (cortisol). • *Producing someandrogens. • *Arrangedvertically. *Producingandrogens. *Arranged incords. *Containing catecholamines (epinephrine & NE) which are synthesized from the aminoacid tyrosine.

11. STATION – 3: AdrenalsHistology Adrenal Medulla

12. STATION – 3: PituitaryHistology Relations to the pituitarygland: Superior: opticchiasma. Inferior: sphenoid bone with sphenoidalsinus. Lateral: cavernoussinuses Posterior: mamillarybodies. Pituitary glanddivisions

13. STATION – 3: PituitaryHistology (Adenohypophysis/Parsdistalis) •Acidophils: secrete GH &prolactin. •Basophils: secrete TSH, ACTH, LH,FSH •Chromophobes: they stainpale

14. STATION – 3: Pituitaryhistology(Neurohypophysis) Herring bodies contain neurosecretory products of the hypothalamic cells. Those areADH &oxytocin. Note: the neural cell bodies are in the hypothalamus and their axons extend to the posterior pituitary where the secretions accumulatein their terminals forming those herringbodies.

15. STATION – 4: Adrenal Glandsanatomy • Location: • Located superiorly on eachkidney • Posterior abdominal wall. • Right adrenal gland:pyramid. • Left adrenal gland:semi-lunar. • Posteriorly: the diaphragm for both right and left adrenalglands. • Shape: • Relations: -Anteriorly: • Right gland: inferior vena cava & right lobe of the liver. • Left gland: pancreas with its vessels, spleen & • stomach+lessersac. • Arterial supply: - Superior suprarenal artery: from inferior phrenicartery. • Middle suprarenal artery: directly from the abdominalaorta. • Inferior suprarenal artery: from renalartery. • Venous • drainage: • Right gland: inferior venacava. • Left gland: renalvein.

16. STATION – 4: Adrenal glandsanatomy

17. STATION – 4: Pituitary GlandAnatomy • Location: • Divisions: • In sella turcica in the middle cranial fossa at the base of thebrain. • Anterior pituitary(adenohypophysis): • Parstuberalis. • Parsintermedia. • Parsdistalis. • Posterior pituitary(neurohypophysis): • Parsnervosa. • Infundibulum (pituitarystalk). • Medianeminence. • Anterior & superior: opticchiasma. • Posterior: mamillarybodies. • Lateral: cavernoussinuses. • Inferior: sphenoid bone and sphenoidalsinus. • Relations: • Arterial supply (branches of internal carotidartery): • Superior pituitary artery: supplying pars tuberalis, infundibulum and medianeminence. • Inferior pituitary artery: supplying the posterior pituitarygland. • Venous drainage: to cavernoussinuses.

18. STATION – 4: Pituitary GlandAnatomy

19. STATION – 4: Pituitary glandanatomy The lateral aspects of the pituitary are adjacent to the cavernous sinuses. From superior to inferior, the cavernous sinus contains cranial nerves III (oculomotor), IV (trochlear), VI (abducens). These cranial nerves supply the muscles of the eye. V1 (ophthalmic branch of trigeminal nerve), and V2 (maxillary branch of trigeminal nerve). The internal carotid artery also courses through the cavernous sinus, medial to thesenerves

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