endocrine pancreas Flashcards
What percentage of pancreatic tissue is composed of endocrine tissue?
1%
Endocrine tissue secretes hormones such as insulin and glucagon.
Which cells in the pancreas secrete insulin?
b cells
Insulin is crucial for regulating blood glucose levels.
Which cells in the pancreas secrete glucagon?
a cells
Glucagon plays a critical role in glucose metabolism.
What role does somatostatin play in the pancreas?
Paracrine role
Somatostatin inhibits insulin secretion.
What triggers the secretion of insulin from the pancreas?
Post-prandial rise in blood glucose
Other factors may modulate this response.
What is insulin’s primary function?
An anabolic hormone
It facilitates the storage of nutrients.
List the three macro-nutrients that insulin helps to store.
- Glucose to glycogen
- Free fatty acids to triacylglycerol
- Amino acids to protein
These processes are essential for growth and energy storage.
What is the role of GLUT 4 in insulin function?
Enhanced glucose uptake from blood
GLUT 4 is a glucose transporter that is regulated by insulin.
What is Type 1 diabetes mellitus characterized by?
Autoimmune destruction of b cells
This leads to a rapid decline in insulin production.
What is Type 2 diabetes mellitus characterized by?
Progressive insulin resistance of tissues
This condition leads to hyperglycaemia with a slower onset.
What are the potential complications of diabetes mellitus?
Low-level chronic inflammation; risk of secondary diseases and blindness
These complications can be severe and life-altering.
What triggers the secretion of glucagon from the pancreas?
Short-term fasting and resultant fall in blood glucose
Glucagon helps to raise blood glucose levels.
How is glucagon characterized in relation to insulin?
Counter-regulatory hormone
It acts to raise blood glucose levels, opposing insulin’s effects.
What is the normal range for blood glucose levels during fasting?
4 to 5.4 mM
Maintaining blood glucose levels within this range is crucial for health.
What is considered clinical diabetes mellitus in a fasting blood glucose test?
Above 7 mM (126 mg/dL)
This threshold indicates potential diabetes.
What is considered clinical diabetes mellitus in a random blood glucose test?
Above 11 mM (200 mg/dL)
This indicates diabetes regardless of when the test is taken.
What is glucagon’s primary function?
Catabolic hormone
It makes fuel available for energy production during fasting.
