The adrenal glands are two small yellowish bodies about 1 inch in length, situated on the upper pole of each kidney. They are surrounded by a capsule of areola tissue containing fats and are supplied with blood from the aorta through renal arteries and nerve supply by sympathetic nerve fibers adrenal glands
The glands are composed of two distinct parts which differ both anatomically and physiologically. The outer part is called the cortex and inner part, the medulla.
The Adrenal cortex
The cortex is yellowish in colour and completely surrounds the medulla. It is essential to life and secretes a number of hormones each having different functions. They are:
1. The Mineral Corticoids:
Of which aldosterone, fludrocortisones and synthetic deoxycortone (DOCA) are examples. They act on the tubules of the kidney in such a way that
(a) Sodium and chloride are retained in the body
(b) Excess of potassium is excreted.
They therefore help to maintain the water and electrolyte balance of the body.
2. The Gluco-Corticoids:
Of which cortical and Corticosterone are examples these have a number of actions, one of the main ones being.
(a) To influence carbohydrate metabolism
(b) They assist in the conversion of carbohydrate into glycogen.
(c) They increase the blood sugar.
(d) They help in the utilization of fat
(e) They tend to decrease the number eosinophil and lymphocytes in the blood and to increase the neutrophil count.
(f) They reduce the body’s response to antigens.
(g) They decrease the absorption of calcium from the small intestine by negating the effect of Vitamin-D.