regulation of blood sugar
TRANSCRIPT
Regulation of Blood Sugar
Pancreas exerts most control over glucose concentration in blood by the secretion of 2 peptide hormones:
1.Insulin2.Glucagon
Anatomy & Histology of the Pancreas
• 2 states of nutrient usage:1. Absorptive: nutrients
absorbed from intestine & into cells
2. Post-Absorptive: nutrients NOT entering body & must be made available from body stores
ROLE OF INSULINRegulates entry of glucose & amino
acids into cellsReleased from -cells in Islets of
Langerhans in Pancreas
FEEDBACK LOOPS
LIPASE ACTIVATED
ISLET -CELLS
INSULIN
CATABOLIC ENZYMES INHIBITED GLYCOGEN
INHIBITED
ANABOLIC ENZYMES STIMULATED
CELLULAR UPTAKE SYSTEMS ACTIVATED
INCR. AMINO ACIDS
INCR. GLUCOSE
CCK
RELEASE OF INSULINHigh blood glucose & amino acid levels stimulate the release from pancreasHormone CCK and Parasympathetic Nervous System also stimulates release
High carb diets increase the density of insulin receptors on -cells making them more sensitive to change
Low carb diets do the opposite
EFFECTS OF INSULINGenerally increases the uptake of glucose by cells
MUSCLESIncrease glucose uptakeIncreases amino acid uptake
LIVERStimulates enzymes that make glycogenInhibits enzymes that break down glycogenStimulate enzymes that synthesize fats
ROLE OF GLUCAGONActs in post-absorptive state (catabolic)Made in -cells of Islets of Langerhans in Pancreas
Stimulates the breakdown of glycogen in the liver and other substances into glucose (a.a.’s & lipids)
REMEMBER GLUCOSE DOES NOT EASILY ENTER CELLS WITHOUT THE PRESENCE OF INSULIN
FEEDBACK LOOPS
INCR IN LEVELS OF FATTY ACIDS & KETONES
ISLET -CELLS
GLUCAGON
ANABOLIC ENZYMES INHIBITED SECRETION OF
INSULIN
GLYCOGEN BREAKDOWN
LIPID & PROTEIN CONVERSION TO GLUCOSE
INCR. AMINO ACIDS
DECR. GLUCOSE
PARASYMPATHETIC ACTIVITY
INSULIN
DIABETESDifferent types of diabetes
Type I (juvenile diabetes, insulin dependent)Genetic predispositionOnset in childhood or early teens
Type II (adult-onset, non-insulin dependent)Obesity – mostly adults 40+Excess sugar in blood stream
Gestational
Frequent urination
Excessive thirst
Extreme hunger or constant eating
Unexplained weight loss
Presence of glucose in the urine
DIAGNOSISThe amount of glucose (sugar) in your blood is measured in mmol/L.
Fasting blood glucose (FPG)You must not eat or drink anything except water for at least eight hours before this test. A test result of 7.0 mmol/L or greater indicates diabetes.
Casual blood glucoseThis test may be done at any time, regardless of when you last ate. A test result of 11.0 mmol/L or greater, plus symptoms of diabetes, indicates diabetes.
Oral glucose tolerance testYou will be given a special sweetened drink prior to this blood test. A test result of 11.1 mmol/L or greater taken two hours after having the sweet drink indicates diabetes.A second test must be done in all cases (except if you have acute signs and symptoms).
TREATMENTS
Insulin injections
Monitoring of blood glucose
Planning of meals (foods & times)
Weight loss
World prevalence of diabetes (per million
persons)
Cost of Diabetes(billions of dollars)