Islets of Langerhans (Pancreas)
Control and Function.:
This is under control of the pituitary tropic hormones STH and ACTH
and also respond directly to level of blood glucose.
Composition:
The islets contain:
Large number of β cells associated with insulin production.
The smaller number of α cells secrete glucagon.
Function of Insulin:
In general, insulin depresses blood glucose levels, in a variety of
ways which include increasing glycogen synthesis and increasing
cell utilization of glucose.
It also stimulates conversion of glucose into lipid and protein,
which in turn reduce glucose levels.
Insulin inhibits the hydrolysis of glycogen in the liver and muscle.
Function of Glucagon:
Glucagon is essentially antagonistic to insulin and causes an
increase in blood glucose levels.
It does this mainly by promoting breakdown of glycogen to
glucose in the liver and muscles.
It also increases the rate of Breakdown of fats.
Control and Function.:
This is under control of the pituitary tropic hormones STH and ACTH
and also respond directly to level of blood glucose.
Composition:
The islets contain:
Large number of β cells associated with insulin production.
The smaller number of α cells secrete glucagon.
Function of Insulin:
In general, insulin depresses blood glucose levels, in a variety of
ways which include increasing glycogen synthesis and increasing
cell utilization of glucose.
It also stimulates conversion of glucose into lipid and protein,
which in turn reduce glucose levels.
Insulin inhibits the hydrolysis of glycogen in the liver and muscle.
Function of Glucagon:
Glucagon is essentially antagonistic to insulin and causes an
increase in blood glucose levels.
It does this mainly by promoting breakdown of glycogen to
glucose in the liver and muscles.
It also increases the rate of Breakdown of fats.
