HORMONES OF ADRENAL CORTEX

HORMONES OF ADRENAL CORTEX

Adrenal glands are situated in the abdominal cavity adjacent to the kidneys. In case of fishes and amphibians the adrenal gland is found embedded in the tissues of the kidney. In reptiles, birds and mammals the Adrenal gland is distinct and independent gland located at the cephalic end of the kidney.
The adrenal gland shows two parts in various animals. The central part constitutes the medulla and the peripheral part is called the cortex. The cortex is derived from the embryonic mesoderm and the medulla is derived from the embryonic ectoderm, thus the hormones originating from them are also of a different nature.
Adrenal medullary hormones viz adrenaline (epinephrine) and non-adrenaline (non epinephrine) are of biogenic amines. The hormones are secreted under the influence of the autonomic nervous system. The Adrenaline regulates the

(i) heart beats.

(ii) Constriction-dilation of blood vessels and

(iii) Blood supply to voluntary muscles.

Adrenaline induces conversion of glycogen to glucose. It increases the rate of activity of Muscle of Trachea i.e. respiration. It retards the peristaltic movement of the wall of stomach and intestine. Adrenaline enhances production of ACTH in the anterior pituitary. Noradrenaline mainly regulates constriction/dilation of the peripheral blood vessels so as to maintain the blood pressure.