Suprarenal gland

1. Debre tabor university
college of health science
department of midwifery
course :- Human anatomy
assignment topic :-the microscopic& gross anatomy
of suprarenal glands
prepared by , kassalem fekadie ID M 1197
Submitted to , berhanu a (Msc)
date of submission 19/7/2014

2. microscopic and gross anatomy of Supra renal
gland
Out line
 Introduction
 describe anatomic strictures of supra renal gland
 Histological features of supra renal glad
 Neurovascular strictures of supra renal gland

3. Introduction
 suprarenal gland are also named as adrenal glands
 are small, triangular-shaped glands located on top of
both kidneys
 produce hormones that help regulate body
metabolism, immune system, blood pressure,
response to stress and other essential functions
 produce a variety of hormones including adrenaline
and the steroids aldosterone and cortisol

4. Anatomic strictures of adrenal gland
 suprarenal glands are located near the top of each
kidney

5. Anatomy cont…
 They are yellowish retroperitoneal organs
 At the level of the last thoracic vertebra (T12)
 They are surrounded by renal fascia (but are
separated from the kidneys by the perirenal fat)
 Each gland has an outer yellow cortex and an inner
dark brown medulla

6. The right suprarenal gland
Relations:
 Anterior: right lobe of the liver and inferior vena
cava
 posterior: diaphragm
 Medial : Celiac plexus and ganglia

7. The left suprarenal gland
 Is crescentic in shape
 Extends along the medial border of the left kidney
from the upper pole to the hilus

8. Left suprarenal gland cont.…
Relations:
• Anterior: pancreas, lesser sac, and stomach
• Posterior: diaphragm.
• Medial : Celiac plexus and ganglia

9. Histologic features of suprarenal gland
the adrenal gland consists of
 an outer cortex of glandular tissue and
 the inner medulla of nervous tissue
 they have different embryological origins and different
functions.

10. Adrenal cortex
Derived from SF-1 expressing cells within the
urogenital ridge of the coelomic cavity epithelium
(i.e., adrenogonadal primordium)
The adrenal cortex is characterized by three layers:
a) Zona glomerulosa ;aldosterone, outer-most layer of
cortex (i.e., sub-capsular)
b) Zona fasciculata; corticosteroids, middle layer of
cortex
c) Zona reticularis; androgens, inner-most layer of
cortex adjacent to medulla

11. Cont…
 Zona glomerulosa; cells are extremely sensitive to
increases in extracellular potassium concentration
and maintain K+ levels by secreting aldosterone
 Zona fasciculata constitutes the bulk of the cortex in
laboratory animals/toxicology species
 The zona reticularis is prominent in humans, but it is
less distinguish

12. Connt…
 Precursor cells located subcapsular/outer ZG
(mitotically active) → centripetal differentiation from
ZG to ZR → apoptosis

13. Medulla
Derived from ectodermal tissue of the neural crest
Precursor medullary cells invade the developing
cortical cells forming the embryonic adrenal, which
migrates cranial to the kidneys
 comprises ~15% of the volume of the adrenal gland

14. Cont….
derived and consists of three types of cells
1. Chromaffin: contains epinephrine (E) cells
norepinephrine (NE) cells, and small granule-
containing cells
The ratios of E/ NE-type cells in young adult rats is
approximately 4/1
 Site of synthesis and storage of catecholamine's
 Derived from a sympathoadrenal neuroblast precursor
 Express neuronal cytoskeletal proteins
 Catecholaminergic

15. Cont….
2. Neuronal (i.e., ganglion-like cells)
 Derived from the same sympathoadrenal precursor
as chromaffin cells
 Express neuronal cytoskeletal protein
 Catecholaminergic

16. Cont….
3. Sustentacular cells (stromal/supportive cells)
 Stromal or supportive cells that are morphologically
and functionally similar to Schwann and satellite cells

17. Blood supply for supra renal glands

18. Blood supply cot….
 As the adrenal glands produce various systemically-
important hormones, they require significant blood
supply and are extremely well vascularized
 three chief sources of blood supply to the adrenal
glands
1. The superior adrenal arteries, which are small
branches coming off the inferior phrenic artery
2. The middle adrenal artery comes directly off the
abdominal aorta
3. The inferior adrenal artery originates from the renal
artery bilaterally

19. Blood supply cot….
 drainage from the adrenal glands is dependent on
the side of the gland
 The left adrenal gland is anatomically further away
from the inferior vena cava, and therefore the left
adrenal vein drains into the left renal vein
 The right adrenal vein is much closer to the inferior
vena cava and drains directly into this large vessel

20. Lymphatic derange
 The lymph drains into the lateral aortic lymph
nodes

21. Nerve supply
 The function of the adrenal gland is mediated by
both synaptic stimulation and hormonal stimulation
 the adrenal medulla is innervated by preganglionic
nerve fibers (type B) arising from the
intermediolateral cell column of the spinal cord's
lateral horn from the T5–T8 spinal cord segment

22.  The blood vessels supplying the adrenal glands will
then receive their innervation from the celiac
ganglion's postsynaptic fibers
 Adrenocorticotropic hormone (ACTH) secreted from
the anterior pituitary gland activates the adrenal
cortex

23. Thank you