click below
click below
Normal Size Small Size show me how
Lecture 47
Fuel Metabolism-Insulin-Diabetes
Term | Definition |
---|---|
Anabolism/Catabolism | balance of buildup of large macromolecules w/ breakdown controlled by activity and energy balance |
Essential Nutrients | some nutrients cannot be made in the body.some amino acids and all vitamins must be in a diet. |
Nutrient Storage | glycogen storage in muscle and liver.fat storage in adipose tissue.body will consume muscle for amino acids during starvation |
Brain Glucose Supply | brain only uses glucose for energy-liver glycogen maintains plasma glucose btw meals.fats cannot be made into glucose-cannot supply energy to brain.if no glucose available,body converts protein to amino acids to glucose. |
Absorptive State | post-meals state-sevral hrs after eating.many utrients available from newly arrived meal.absorption carbs,then protein,then fats |
Post-Absorptive State | btw meals,fasting.use stored energy to supply tissues energy needs |
Islet Cells | in pancreas-secrete hormones into blood.alpha cells secrete glucagon.bata cells secrete insulin.secretion inc plasma glucose leads to inc insulin secretion.leave capillaries through pores. |
Insulin Effects | all aimed at storing energy for future use. |
Carbohydrates | seconds:ijc # of glucose transporters by fusion of membrane transporter vesicles.inc glucose entry into cells.brain and working skeletal muscle dont need I. minutes:inc glycogen storage in liver and muscle. |
Fats | hours:inc lipid storage |
Proteins | seconds:inc amino acid entry into cells.minutes: inc liver glycogen storing enzymes and protein synthesis. |
Regulation of Insulin Secretion | inc plasma glucose leads to inc insulin release ~ 1 hr dec glucose causes dec insulin release.sugar meal has rapid rise and fall in glucose, I stays high.hypoglycemia after sugar meal as I stays high after sugar transport complete. |
Glucagon | opposite of insulin inc breakdown-liberates glu from storage. inc lipid release inc glu production by liver dec plasma glu leads to inc glucagon release.inc plasma glu leads to dec glucose release.other hormones (ep,cortisol) also cause inc plasma glu. |
Diabetes Mellitus | glucose in urine.type 1-10%-autoimmune attack on beta cells.type 2-90%-obesity and age-dec of I recpetors. |
Hyperglycemia | inc plasma glucose.hemoglobin a1c test-long term glucose indicator.inc blood osmolarity leads to exceeds tm for glucose. |
Dehydration | inc urine volume.loss of na+ and k+. dec blood volume leads to dec bp leads to shock leads to death. |
Protein Metabolism | amino acids used for energy and to make glucose in liver.negative protein balance and wasting |
Fat Utilization | use fats for energy in insulin dependent tissue (most). fat use inc plasma fatty acids and cholesterol leads to inc atherosclerosis. |
Acidosis | fat metabolism leads to inc ketone bodies (4c keto acids) inc ketosis leads to inc acidosis leads to inc breathing rate,dec mental activity. |
Coma | acidosis,dehydration,hyperosmolarity can all induce coma in diabetes and some coma leads to death. |
Type 1 Diabetes Mellitus | juvenile diabetes.most prominent in teens,but can occur at other ages.autoimmune attack-immune attack gradually destroys beta cells over a few years.gradual loss of insulin production-hyperglycemia develops. |
Type 2 Diabetes Mellitus | loss of insulin receptors associated w/ obesity in people under 40.symptoms like type 1. |
Obesity | prolonged,elevated glucose leads to constant insulin production.elevated insulin leads to down regulation of insulin receptors. leads to dec glucose entry and hypoglycemia.reducing caloric intake helps. |
Age | in elderly people, dec receptor # or receptor availability.not necessarily associated w/ obesity but inc weight can inc probability.may take some insulin maximize available receptors. |
Regulation of Insulin Secretion cont | starch meal takes longer to ingest glucose-glucose and insulin never get as high-no hypoglycemia. |