ADRENAL GLANDS
, ADRENAL GLANDS
• The Adrenal Glands (also called the Suprarenal Glands) in man are
paired organs located within the retroperitoneal adipose tissue at
the superior pole of each kidney.
• The glands are roughly triangular and flattened in appearance and
each gland weighs about 4 grams in normal adult.
Blood Supply:
• The adrenal glands are supplied with blood from branches of the
renal and phrenic arteries.
• Venous blood drains via a central adrenal vein (collecting vein)
at the junction of the cortex and medulla.
• Each gland consists of two parts, the outer Cortex and the inner
Medulla.
• These two parts differ markedly in their embryonic origins,
morphology, hormonal secretions and function. Hence each
gland is a two distinct endocrine organs located within a common
structure.
,Mechanism of Action of Steroid Hormones
,Functions of Glucocorticoids
• At least 95% of the glucocorticoid activity of the
adrenocortical secretions results from the secretion of
cortisol, known as hydrocortisone. In addition to this, a
small but significant amount of glucocorticoid activity is
provided by corticosterone. The functions are considered
below:
1. Carbohydrate metabolism: Cortisol and other
glucocorticoids have various effects on CHO metabolism,
resulting in the raising of blood glucose concentration.
• By far the best known of this effects is their ability to
stimulate gluconeogenesis by the liver often increasing
the rate of gluconeogenesis as much as 6-10 fold.
, ADRENAL GLANDS
• The Adrenal Glands (also called the Suprarenal Glands) in man are
paired organs located within the retroperitoneal adipose tissue at
the superior pole of each kidney.
• The glands are roughly triangular and flattened in appearance and
each gland weighs about 4 grams in normal adult.
Blood Supply:
• The adrenal glands are supplied with blood from branches of the
renal and phrenic arteries.
• Venous blood drains via a central adrenal vein (collecting vein)
at the junction of the cortex and medulla.
• Each gland consists of two parts, the outer Cortex and the inner
Medulla.
• These two parts differ markedly in their embryonic origins,
morphology, hormonal secretions and function. Hence each
gland is a two distinct endocrine organs located within a common
structure.
,Mechanism of Action of Steroid Hormones
,Functions of Glucocorticoids
• At least 95% of the glucocorticoid activity of the
adrenocortical secretions results from the secretion of
cortisol, known as hydrocortisone. In addition to this, a
small but significant amount of glucocorticoid activity is
provided by corticosterone. The functions are considered
below:
1. Carbohydrate metabolism: Cortisol and other
glucocorticoids have various effects on CHO metabolism,
resulting in the raising of blood glucose concentration.
• By far the best known of this effects is their ability to
stimulate gluconeogenesis by the liver often increasing
the rate of gluconeogenesis as much as 6-10 fold.
