Adrenal Glands are two in number and each one is located on the anterosuperior aspect of each kidney.
The adrenal gland is an important gland of the body which secretes many important hormones which control various important functions of the human body.
When we cut adrenal gland cross-sectionally we see two distinct regions. The outer one is called Cortex and the inner zone is called medulla. Each zone consists of different cells which secrete different hormones.
The Cortex is further divided into three layers.
- The outer one is called zona glomerulosa
- The middle is called zona fasciculata
- and the innermost layer is called zona reticularis.
Adrenal Cortical Hormones:
Adrenal cortical hormones secretion is controlled by the level of ACTH (adrenocorticotrophic hormone). ACTH is secreted by the pituitary gland.
following hormones are secreted by different zones of the adrenal gland.
Zona glomerulosa secretes mineralocorticoids especially Aldosterone - Aldosterone controls blood volume and blood pressure. it is involved in haemodynamics.
Zona fasciculata secretes glucocorticoids. The most important one is called cortisol. Cortisol is involved in stress and it is an important hormone in managing stress.
Zona reticularis secretes Androgens. These hormones are responsible for the development of sexual Characteristics.Adrenal Medullary Hormones:
The adrenal medulla secretes two important hormones, epinephrine and nor epinephrine. these are also called adrenaline (epinephrine) and non-adrenaline (nor epinephrine). These hormones help to fight with the stressful condition, control blood pressure, increase heart rate, affect body metabolism and various other functions.