Adrenals, Pancreas, Gonads, Other Tissues

The Adrenal Glands Location: on top of the kidneys Description: Bean-shaped Actually like two organs in one Cortex (more glandular; surrounds medulla) Medulla (more neural, in center) http://upload.wikimedia.org/wikipedia/commons/c/cf/Illu_thymus.jpg http://www.hormone.org/~/media/Hormone/Images/Endo%20101/Thymus.jpg?h=310&w=200

Adrenal Cortex 3 major groups of steroid hormones Collectively called corticosteroids Mineralocorticoids Glucocorticoids Sex hormones http://upload.wikimedia.org/wikipedia/commons/e/ee/Thymosin_1HJ0.png

Mineralocorticoids Produced by outermost cortex layer Regulate water and electrolyte (salt, mainly Na+ and K+) balance Target tissue: kidney tubules Main one is aldosterone

Glucocorticoids Produced by middle cortical layer Helps body cope with prolonged or continuing stressors When these are high, fats and proteins are broken down and glucose is added to the blood If constantly stressed, may lead to weight gain around waist Help control inflammation (decreases edema) and reduces pain Main ones are cortisone and cortisol

Sex Hormones Most produced by inner cortex layer are male androgens Some estrogens are formed as well Produced throughout life in relatively small amounts

The adrenal glands ADDISON’S DISEASE: hyposecretion of all adrenal cortex hormones Peculiar bronze tone to skin Problems with electrolyte and water balance Muscles become weak Hypoglycemia Lessened ability to cope with stress Suppression of immune system

The adrenal glands CUSHING’S SYNDROME: hypersecretion of glucocorticoids Swollen “moon face” Appearance of a “buffalo hump” of fat on the upper back High blood pressure Hyperglycemia Weakening of the bones Severe depression of immune system

The adrenal glands MASCULINIZATION: hypersecretion of sex hormones Can occur in either sex In males, effects can be masked In females, results are more dramatic Beard can develop Masculine pattern of hair distribution

Adrenal Medulla When stimulated by sympathetic neurons, the medullary cells release catecholamines Adrenaline/epinephrine Noradrenaline/norepinephrine http://upload.wikimedia.org/wikipedia/commons/e/ee/Thymosin_1HJ0.png

Catecholamines When you feel (or are) physically or emotionally threatened, “fight or flight” response occurs Medulla stimulated; hormones into blood Prepares body to cope with brief or short-term stressful situations Increases heart rate, blood pressure, blood glucose levels Dilates small passageways of the lungs

The adrenal glands Hypersecretion of catecholamines keeps body in “fight or flight” mode Rapid heart beat, high blood pressure Tendency to perspire and be irritable Treatment: surgical removal of the catecholamine-secreting cells

Be ready to answer! Which hormone stimulates the kidneys to reabsorb more sodium? Which group of hormones produced by the adrenal cortex has some of the same effects as the hormones of the ovaries and testes? A man has a heart attack and is hospitalized. Would you expect his wife’s blood glucose levels to be elevated, normal, or lower than normal? Why?

Summary- be ready to answer! Match! Calcitonin Glucocorticoids Mineralocorticoids Parathyroid hormone Sex hormones T3/T4 Decreases blood calcium levels Help the body resist long-term stressors Increases blood calcium levels Main metabolic hormone of the body Regulate water and electrolyte levels in blood Small amounts of male and female hormones

Summary- be ready to answer Summary- be ready to answer! Decide if each is caused by hypersecretion or hyposecretion of each respective hormone. Hashimoto’s disease/thyroid hormones Grave’s disease/thyroid hormones Cretinism/thyroid hormones Myxedema/thyroid hormones Tetany/parathyroid hormones Cushing’s syndrome/adrenal cortex hormones Addison’s disease/adrenal cortex hormones

Pancreas Location: abdominal cavity, near stomach Description: Most of it is exocrine (enzyme-producing): part of digestive system Feather-like appearance Endocrine portion: Islets of Langerhans (or Pancreatic Islets) With Alpha & Beta cells Hormones: Insulin and glucagon

Insulin When glucose is high in the blood, beta cells release insulin Target: almost all cells Promotes uptake by cells Decreases glucose levels in blood Once in cells, glucose is used for energy, or converted to glycogen or fat for storage

Glucagon Antagonist of insulin Alpha cells release it when blood levels of glucose are low Main target organ: the liver Causes liver to release stored glucose (glycogen) into blood Increases blood sugar levels

Abnormalities Diabetes Mellitus: cells cannot use glucose; islet cells do not make enough insulin or cells do not respond to it. 3 kinds: Type I/Juvenile Type II Gestational

Type I Diabetes Before age 30 Less common, more severe Autoimmune destruction of insulin-producing cells Treatment: blood sugar monitoring, insulin injections

Type II Diabetes In adults, but become more common in younger people Associated with being overweight Insulin secreted but cells do not respond (sugar stays in the blood) Treatment: diet, oral medication, weight reduction

Gestational Diabetes During pregnancy Due to hormones secreted by the placenta Usually disappears after childbirth If not treated- complications for the mother and child