The Stress Response & Blood Sugar Regulation Miss Richardson SBI4U

The Adrenal Glands The body has two adrenal glands, located above the kidneys Two-layered glands: Adrenal medulla, inner layer Adrenal cortex, outer layer

Adrenal Medulla Regulates short-term stress response Hypothalamus activates sympathetic nervous system, stimulating adrenal gland Adrenal gland secretes epinepherine and norepinepherine Increased metabolism Increased breathing rate, heart rate, blood pressure, blood flow, conversion of glycogen to glucose Eyes dilate, blood flow to extremities decreases

Adrenal Cortex Regulates long-term stress response Hormones: - glucocortitoids - mineralcortitoids - gonadocorticoids

Cortisol Most abundant glucocortitoid Steroid hormone When the brain detects danger, hypothalamus stimulates secretion of ACTH (adrenocorticotropic hormone) from pituitary gland ACTH stimulates adrenal cortex to release cortisol Raises blood sugar ACTH production is suppressed in the negative feedback system and cortisol production ceases

Aldosterone Main mineralcortitoid Responsible for water-ion balance Stimulates kidneys to increase sodium absorption Increased concentration of solute increases water absorption in kidney Blood pressure raises

The Pancreas Islets of Langerhans are the endocrine cells throughout the pancrease Beta cells: secrete insulin, decreasing blood sugar Alpha cells: secrete glucagon, increasing blood sugar

Glucose Imbalance Diabetes mellitus 285 million people worldwide affected Body doesn’t produce sufficient insulin Increased glucose levels – hyperglycemia Fatigue Bad breath (ketone production due to fat/protein metabolism) Thirst High-glucose urine Blindness, kidney failure, nerve damage, gangrene Type 1 – insulin dependent Type 2 – adult-onset