Adrenal gland Flashcards
Where are the adrenal glands located?
Situated superiorly over the medial and superior aspect of the kidney
Which hormones are secreted by the adrenal glands?
Secretes steroids and catecholamine hormones into systemic circulation
(Sex-steroids, epinephrine, norepinephrine, adrenaline, noradrenaline, mineralcorticoids, glucocorticoids)
what shape is the right adrenal gland?
Pyramidal shape, contracting with the semi-lunar shape of the left gland
Which type of fascia encloses the adrenal glands?
Perinephric fascia
What is the anatomical relationship between the spleen and adrenal glands?
The left adrenal gland resides inferior to the spleen
Where does the left adrenal vein drain into?
Traverses into the renal vein
Where does the right adrenal vein drain into?
inferior vena cava
How many arteriole branches supply each adrenal gland?
57 arteriole branches
What is the outer adrenal gland called?
Cortex
What is the inner adrenal gland?
Medulla
What are the three layers of the adrenal cortex?
Zona glomerulosa, zona fasciata, zona reticularis
Which hormones are secreted from the Zona glomerulsosa?
Aldosterone (mineralcorticoids)
Which hormone is secreted from the zone fasciulata?
Cortisol
Small proportions of androgens
Which hormone is secreted by the zone reticularis?
Androgens and oestrogens
Smaller proportions of corticosteroids
Which cells are located within the adrenal medulla?
Chromaffin/neuroendocrine cells
Which hormones are secreted by the adrenal medulla?
Adrenaline and noradrenaline(+dopamine)
Which molecule are steroids derived from?
Cholesterol
How many carbon atoms are present in cholesterol?
27
What is the structure of cholesterol?
Cyclic rings
How is cholesterol converted into pregnenolone?
Side chain cleavage (p450scc)
How is pregenenlone converted into progesterone?
3-beta-hydroxy steroid dehydrogenase(3BHSD)
Step 1 for progesterone>aldosterone synthesis?
21-hydroxylase converts progesterone into 11-dexoycorticosterone
Step 2 for progesterone>aldosterone synthesis?
11-hydroxylase converts 11-deoxycorticosterone into corticosterone
Step 3 for progesterone>aldosterone synthesis?
18-hydroxylase converts corticosterone into aldosterone
Describe the pathway of molecules for cholesterol to cortisol synthesis?
Cholesterol –> Pregnenolone –>Progesterone –> 17-hydroxy-progesterone –> 11-deoxycortisol –> cortisol
Which enzymes are involved with cortisol synthesis?
17-hydroxylase
21-hydroxylase
11-hydroxylase
Which hormone influences the synthesis of cortisol?
ACTH
How is cortisol predominantly transported within the body?
Corticosteroid binding globulin
Which transport protein transports 15% of cortisol?
Albumin
Which form of cortisol is active?
Unbound form (10%)