Veterinary Physiology-III

ADRENAL CORTEX

• The adrenal gland also called suprarenal glands is composed of an outer portion-the cortex (80 to 90% of gland) which secretes corticosteroids and the inner portion-the medulla (10 to 20% of gland) which secretes catecholamines
• In mammals the adrenal cortex is organized into three zones.
• The outer zone, zona glomerulosa secrete the hormones mineralocorticoids
• The middle zone, zona fasciculata secrete the hormones glucocorticoids.
• The innermost zone, zona reticularis secrete androgens
• The mineralocorticoids play an impor­tant role in electrolyte balance and also in the regulation of blood pressure. The major mineralocorticoid is aldosterone.
• The glucocorticoids are important in the regulation of metabolism either directly or through an interaction with other hormones. The major glucocorticoid is cortisol.
• The adrenal sex steroids are secreted from the inner layers.
• Adrenal cortex is essential for life.

Adrenal cortex layers

Picture source : Wikipedia