The Adrenal Gland is a bilateral Structure which is situated above the Kidneys. It is divided into the Medulla and the Cortex. The Cortex is divided into 3 layers:
Zona Glomeruosa – Secretes Aldosterone ( aka Glomeruls makes sense)
Zona Facicularis, – Involved in secreting Cortisol
Zona Reticularis, – Secretes Androgens
( An easy way to memorize this is The deeper you go the sweeter it gets )
and remember F comes before R ) and you have the tree layers.
Glomerulosa secretes aldoseterone relating to salt
Facicularis secretes ( cortisol which mobilizing sugars)
Reticularis secretes ( sex Hormones which is always Sweet!!)
These three layers are responsible for secreting specific Hormones, such as Glucocorticoids,
Minerocorticoids and Androgens. The Medulla is responsible for secreting epinephrine and
The Outer most layer of the Adrenal Cortex, ( zona granulose) is highly influenced by angiotensin II which is synthesized by the Lung via (ACE) Angiotensin Converting Enzyme. Angiotensin II acts on the adrenal Gland To secrete Aldosterone (A Mineral-Corticoid) which acts on the Kidneys (Distal Convoluted tubule to increase Salt absorption.)
Deficiencies in Aldosterone results in:
1) Decrease Na
2) Decrease Plasma Volume
3) Decrease Blood Pressure.
With the absence of glucocorticoids, ( Cortisol ) this is an important stress hormone, which is
influenced by ACTH from the Anterior Pituitary.
Deficiencies In Cortisol Result in:
1. Circulatory Failure
2. Deficiencies in mobilizing energy Stores ( Fats, Sugars Glycogen)
3. In severe cases may result in Fatal hypoglycemia
(THIS PORTION OF THE ADRENAL GLAND IS NOT EFFECTED BY ACTH,
THUS PITUITARY TOMORS HAVE NO EFFECT ON CATACHOLAMINES)
Deficiencies with this portion of the Gland result in inadequate amounts of Norepinephrine and Epinephrine,
( Catacholamines ).
Deficiencies In Catacholamines Result in:
1) Decreased Mobilization of Glycogen
2) Decreased Flight or Fight Response
Conn’s Disease (Primary HyperAldosteroneism)
Aldosterone is secreted by the adrenal glands. In Primary Hyperaldosteronism there is increased secretion of
aldosterone which leads to elevated salt retention, with concomitant K+ Wasting . The finding of Hypertension with
HYPER NATREMIA and HYPO KALEMIA is key to the diagnosis.
The most likely cause of the Elevated aldosterone is a mineral corticoid secreting adrenal adenoma, It can however
be due to adrenal hyperplasia as well.
Signs and Symptoms
5) Elevated Aldosterone/Renin Ratio >30
The diagnosis is suspected based on clinical findings… High BP…. High NA…. and Low K+.
The FIRST STEP in diagnosis, is Get and Aldo/ Renin Ratio. If > 30 then the clinician should progress to the next step.
Next, a Na+ Loading Test is done . In this case, the Saline loading will also FAIL TO SUPPRESS ALDOSTERONE.
Here the Diagnosis is Made!!!
A CT Scan is Done however to locate the Offending ADENOMA… Remember there are two adrenals.
Treatment – Surgery, to remove the adenoma, and SPIRONOLACTONE TO CONTROL THE BP