Stress-Response
Acute Stress Response: Metabolic
Purpose: to increase levels of glucose within the bloodstream
During stress, glucocorticoids and plasma catecholamines act to increase levels of glucose within the bloodstream:
- glucose uptake is inhibited and synthesis of proteins, fatty acids and glycogen is halted
- lipolysis: triglycerides (fatty acids) are broken down and flushed into bloodstream
- glycogenolysis: glycogen is degraded and glucose is flushed into the bloodstream
- proteolysis: proteins are degraded into amino acids and flushed into bloodstream
- gluconeogenesis: fatty acids and amino acids are converted into glucose within the liver
- E/NE acts at adrenergic receptors (membrane) to rapidly increase blood glucose levels via lipolysis, glycogenolysis, proteolysis, gluconeogenesis; in addition, these hormones act to inhibit secretion of insulin while increasing secretion of glucagon
- glucocorticoids act at intracellular receptors to increase the synthesis of enzymes (via gene transcription) that subsequently act to increase the process of gluconeogenesis; this effect is slower but can last for a longer period of time