4 hours during & after a meal. Nutrients are being absorbed and then immediately used or stored.
nutrient metabolism during the absorptive period
1. Energy is provided primarily by absorbed carbohydrate in a typical meal
2.There is net uptake of glucose by the liver
3. Some carbohydrate is stored as a glycogen in liver and muscle, but most carbohydrates and fats in excess of that used for energy are stored as fat in adipose tissue
4. There is some synthesis of body proteins, but some of the amino acids in dietary protein are used for energy or converted to fat
post absorptive state
after 4 hours (1) break down of glycogen (2) break down of triglicerides (3) gluconeogenesis from lipids and amino acids present (4) oxidation of amino acids to form ATP - hormones involved, glucagon, epi and nor
increase in plasma glucose
increase of insuling secretion by pancreatic islet beta cells- reults in increase in plasma insulin- thus increasing glucose uptake b adipocytes and muscles and liver- final result is restoration of plasma glucose to normal
*GIP- glucose-dependent insulnotropic peptide
*GLP-1- glucagon like peptide 1. Promotes the release of insulin
net result of cortisol on organic metabolism
Increased plasma concentration of amino acids, glucose, and free fatty acids.
glucagon xs, decreased glucose uptake, liver produces more glucose, increased protein catabolism, increased lipolysis, increased plasma H (acidosis), increased renal filtration of glucose and ketones, increase in sodium and water excretion