PANCREATIC HORMONES:
Endocrine Function: Produces Hormones
(Exocrine Function: Produces Pancreatic juice (Enzymes & Bicarbonate))
1. INSULIN
2 peptide chains bonded via disulfide bridge
MUST BE ACTIVATED: produced as a precursor (one chain of peptide) in the form of Pre-Pro-Insulin.
1. End of pre-pro-insulin chain is removed in the ER
2. 2 residues of Arg, a fragment of Lys-Arg & peptide C fragment is removed in the golgi, forming insulin.
Effects :
PROCESS OF ACTION:
1. Hormone attaches to Enzyme receptors (with specific tyrosine
kinase activity), which stimulates phosphorylation processes,
activating GLUT-4 (transporter for glucose) Anabolic role:
2. Glucose is phosphorylated to glucose,6,phosphate in the tissues.
INHIBITORY ROLE:
ATP generates cAMP and is converted into
AMP catalyzed by phosphodiesterase.
-> Insulin activates enzyme Phosphodiesterase
(ACTS AS ANTI-cAMP FACTOR)
2. GLUCAGON
Acts in the cell by increasing the concentration of cAMP, activating protein kinase A, which phosphorylates metabolic
enzymes.
important
enzymes →
T
Endocrine Function: Produces Hormones
(Exocrine Function: Produces Pancreatic juice (Enzymes & Bicarbonate))
1. INSULIN
2 peptide chains bonded via disulfide bridge
MUST BE ACTIVATED: produced as a precursor (one chain of peptide) in the form of Pre-Pro-Insulin.
1. End of pre-pro-insulin chain is removed in the ER
2. 2 residues of Arg, a fragment of Lys-Arg & peptide C fragment is removed in the golgi, forming insulin.
Effects :
PROCESS OF ACTION:
1. Hormone attaches to Enzyme receptors (with specific tyrosine
kinase activity), which stimulates phosphorylation processes,
activating GLUT-4 (transporter for glucose) Anabolic role:
2. Glucose is phosphorylated to glucose,6,phosphate in the tissues.
INHIBITORY ROLE:
ATP generates cAMP and is converted into
AMP catalyzed by phosphodiesterase.
-> Insulin activates enzyme Phosphodiesterase
(ACTS AS ANTI-cAMP FACTOR)
2. GLUCAGON
Acts in the cell by increasing the concentration of cAMP, activating protein kinase A, which phosphorylates metabolic
enzymes.
important
enzymes →
T
