PSL300H1 Lecture Notes - Lecture 6: Anabolism, Alpha Cell, Exocrine Gland
Lecture 6 notes
âą Insulin
o Hormone made by the pancreas specialized cells called beta cells, it takes glucose and
puts it in to the cells
o Prevents hyperglycaemia
o Stimulates by high glucose, GLP1, PNS
o Decreases blood glucose, and heavily involved in growth, promotes anabolic pathway
âą Glucagon
o Prevents low blood sugar in the body, hypoglycaemia
o Alpha cells in pancreas secrete glucagon in response to low blood sugar
o It takes glycogen from the cells and breaks it down in to glucose for use
âą GLP-1
o Stimulates insulin secretion, increases beta cell mass
o Released from intestine
o Decreases our appetite and glucagon
âą Metabolism
o Sum of all chemical reactions in the body
o 2 states
âȘ Fed, absorptive, anabolic, (insulin)
âȘ Fasted, post absorptive, catabolic, (glucagon)
o Basil metabolic rate BMR
âȘ An individuals energy expenditure when resting
âȘ On the diagram any left side to the right side, it is anabolic, insulin (building up
larger molecules from smaller; glucose to glycogen)
âą Insulin takes glucose and puts it into the cell making glycogen, process
called glycogenesis
âą All going to the left side of the diagram are catabolic
o Breaking down larger molecules to make energy
o Glucagon takes glycogen and breaks it down in to glucose
âą Pancreas
o 98% of it is an exocrine gland
âȘ Majority will make enzymes that will be put into the small intestine to facilitate
digestion
o 2% is called the Islet of Langerhans
âȘ Made of beta cells, delta cells, and alpha cells that secrete endocrine hormones
âȘ Beta cell releases insulin that binds to a receptor-enzyme complex to signal
secondary messenger system, phosphorylating proteins triggering cell response
âȘ Alpha cell releases glucagon that binds to G protein-coupled receptor to trigger
secondary messenger systems phosphorylating proteins and triggering cell
response
