Chapter 16 - Adrenal Medulla and Pancreas

adrenal medulla

neural tissue that acts as part of the CNS

adrenal cortex

secretes steroid hormones called corticosteroids

zona glomerulosa

most superficial of the adrenal cortex zones, mineralocorticoids (aldosterone)

Aldosterone

primarily regulates electrolyte (Na, Ca and K) concentration in the extracellular fluid. Reduces Na excretion from the body and reduces elevated K+ by excretion

zona fasciculata

glucocorticoids (cortisol)

cortisol

stress hormone and is high in the early morning

hyposecretion of corticoids

Addison's disease: glucocorticoid and mineral corticoid deficits. Weight loss, increased ECF concentration of K, decreased Na levels, severe dehydration and hypotension

hypersecretion of corticoids

cushing's syndrome

zona reticularis

secretes androgens

androgens

the main class of male sex hormones

adrenogenital syndrome

masculinization in women or premature sexual development in children; result of abnormal secretion of adrenocortical hormones, especially androgens

Medullary chromaffin cells

synthesize epinephrine (80%) and norepinephrine (20%)

epinephrine and norepinephrine

vasoconstriction, increase HR, increase blood glucose and diverts blood to the brain, heart and skeletal muscles

acinar cells

enzyme secreting cells of the pancreas that are exocrine cells

pancreatic islets

alpha cells (glucagon) and beta cells (insulin) that are endocrine cells

Insulin

A protein hormone synthesized in the pancreas that regulates blood sugar levels by facilitating the uptake of glucose into tissues therfore lowering blood glucose levels

Glucagon

A protein hormone secreted by pancreatic endocrine cells that raises blood glucose levels; an antagonistic hormone to insulin.

Alpha cells

secrete glucagon

beta cells

secrete insulin

diabetes mellitus

a group of metabolic disorders characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both

type 1 diabetes mellitus

diabetes in which no beta cell production of insulin occurs and the patient is dependent on insulin for survival (hyposecretion of insulin)

type 2 diabetes mellitus

diabetes in which either the body produces insufficient insulin or insulin resistance (a defective use of the insulin that is produced) occurs; the patient usually is not dependent on insulin for survival (hypoactivity of insulin)

polyuria

excessive urination

polydipsia

excessive thirst

polyphagia

excessive hunger