Pancreas and glucose regulation

Endocrine hormones

Secrete hormones directly to the bloodstream

Exocrine hormones

Secrete hormones into ducts.

Alpha cells

Alpha cells secrete glucagon

Beta cells

Beta cells secrete insulin.

Isle of langerhans

LIGHT

• endocrine hormones, secrete alpha and beta hormones

Pancreatic Acini

DARK

• exocrine tissue, secrete digestive enzymes

Glycogenesis

Synthesis of glycogen from glucose

Glycogenolysis

breakdown of glycogen to produce glucose

Gluconeogenesis

Synthesis of glucose from fats/amino acids

Glycolysis

Breakdown of glucose

Insulin release

HIGH BG:

• glucose transported and metabolised to form ATP.

• ATP causes K+ to close and accumulate in cell (depolarises)

• opens Ca2+ channels

• Cause vesicles containing insulin to fuse w cell membrane

• released by exocytosis

Insulin action (increase in glucose)

• Binds to a receptor, activating the cell.

• Series of reactions occur including formation of a secondary messenger.

• cAMP triggers responses: glycogenesis/glycolysis(lipids.)

Glucagon action(decrease in glucose)

• binds to a receptor on liver cells, activating the cell.

• series of a reactions occur including formation of secondary messenger.

• cAMP triggers responses: gluconeogenesis/glycogenolysis