HORMONAL INFLUNCES ON CARBOHYDRATE
METABOLISM
Endocrine organs play an important key role on carbohydrate
metabolism to maintain homeostasis. There are two categories
of endocrine influences.
1. Influencing fundamental regulatory mechanisms
They are essential for normal carbohydrate metabolism. Eg:
insulin, hormones of adrenal cortex and anterior pituitary
hormones.
2. Other hormones influencing carbohydrate metabolism
They are not essential for auto regulation under normal
conditions. Eg: hormones of adrenal medulla and hormones
of thyroid gland.
INSULIN
It is a polypeptide having two chains and is produced by
beta cells of islets of langerhans of the pancrease.
It is released into blood stream under the direct influence of
hyperglycemia.
Stimulates the synthesis of various enzymes like Glucose 6-
phosphate dehydrogenase, 6- phosphogluconate
dehydrogenase, ATP citrate lyase.
It has regulatory influence upon the activity of glucokinase
in liver
, Promotes transport of aminoacids across the cell
membrane, those stimulating protein synthesis
Inhibits ketogenesis and promote lipogenisis
Insulin lowers blood glucose concentration by
Increase in uptake of glucose by extra hepatic tissues
Promoting and glycogenisis in both liver as well as in
muscles.
Suppressing glycogenolysis (break down of glycogen)
in the liver and kidney
Suppressing gluconeogenisis
GLUCOCORTICOIDS
They are steroids secreted by the adrenal cortex. ‘cortisol’ is a
major glucocorticoid found in the blood.
It increases blood glucose level by gluconeogenisis (synthesis of
glucose from non carbohydrate sources) as a result of,
Stimulation of protein catabolism in peripheral tissues
Increased hepatic uptake of aminoacids and increasing the
activity of transaminases.
Promotes gluconeogenisis in the liver and the activity of all
the enzymes concerned with it. Eg : pyruvate carboxylase,
PEP carboxylase, glucose-6- phosphatase.
METABOLISM
Endocrine organs play an important key role on carbohydrate
metabolism to maintain homeostasis. There are two categories
of endocrine influences.
1. Influencing fundamental regulatory mechanisms
They are essential for normal carbohydrate metabolism. Eg:
insulin, hormones of adrenal cortex and anterior pituitary
hormones.
2. Other hormones influencing carbohydrate metabolism
They are not essential for auto regulation under normal
conditions. Eg: hormones of adrenal medulla and hormones
of thyroid gland.
INSULIN
It is a polypeptide having two chains and is produced by
beta cells of islets of langerhans of the pancrease.
It is released into blood stream under the direct influence of
hyperglycemia.
Stimulates the synthesis of various enzymes like Glucose 6-
phosphate dehydrogenase, 6- phosphogluconate
dehydrogenase, ATP citrate lyase.
It has regulatory influence upon the activity of glucokinase
in liver
, Promotes transport of aminoacids across the cell
membrane, those stimulating protein synthesis
Inhibits ketogenesis and promote lipogenisis
Insulin lowers blood glucose concentration by
Increase in uptake of glucose by extra hepatic tissues
Promoting and glycogenisis in both liver as well as in
muscles.
Suppressing glycogenolysis (break down of glycogen)
in the liver and kidney
Suppressing gluconeogenisis
GLUCOCORTICOIDS
They are steroids secreted by the adrenal cortex. ‘cortisol’ is a
major glucocorticoid found in the blood.
It increases blood glucose level by gluconeogenisis (synthesis of
glucose from non carbohydrate sources) as a result of,
Stimulation of protein catabolism in peripheral tissues
Increased hepatic uptake of aminoacids and increasing the
activity of transaminases.
Promotes gluconeogenisis in the liver and the activity of all
the enzymes concerned with it. Eg : pyruvate carboxylase,
PEP carboxylase, glucose-6- phosphatase.
