Endocrine System (Ch. 11)

Endocrine glands

Ductless glands that secrete hormones directly into the surrounding vascular and lymphatic systems

What are the primary endocrine glands of the body?

Pituitary gland, pineal gland, 2 adrenal glands, thyroid gland, parathyroid gland, thymus gland

Humoral stimuli

Involve a direct response to changes in extracellular fluids 

Neural stimuli 

Occur when the nervous system directly stimulates the gland to release the hormones 

Hormonal stimuli

Involve a response to other hormones secreted in the body

Pituitary gland

Considered the “master endocrine gland” and is located below the hypothalamus at the base of the brain within the sella turcica of the sphenoid bone 

Pineal gland

Located within the cranium, posterior to the third ventricle, superior to the midbrain, and is controlled by the hypothalamus

Adrenal glands

Pyramid-shaped. glands located on the upper poles of the kidneys

Thyroid gland

Located anterior to the trachea just below the larynx; regulates weight, energy levels, and metabolism 

Parathyroid glands

Located posterior to the thyroid gland; increases calcium absorption in the kidneys and GI system

Pancreas

Located mid-abdomen, posterior to stomach; functions as both an endocrine and exocrine organ

Glucagon

Promotes the breakdown of glycogen to glucose within the liver, glucose is ultimately released into the bloodstream 

Insulin

Produced by B-cells to inhibit the breakdown of glycogen to glucose

Osteopenia

Demineralization of bone

Osteoporosis

Metabolic bone disorder in which the structural integrity of the trabecular pattern of bone is destroyed and bone fragility and fxs occur 

Osteomalacia

Condition of bone softening and a lack of mineralization of bones caused by insufficiency of calcium in tissues and failure of bone tissue to calcify

Rickets

Occurs when osteomalacia occurs before growth plate closure

Pseudofractures

Presence of bands of radiolucency within the bone

Paget disease

Common, chronic metabolic bone disorder characterized by excessive abnormal bone remodeling

Acromegaly

Endocrine disorder that results in skeletal deformity and endocrine dysfunction duet the excessive secretion of growth hormone in skeletally mature patients 

Pituitary gigantism

When excess secretion of growth hormone occurs before the growth plates are fused

DIabetes insipidus (DI)

Most common and serious form of DI, results from damage to the pituitary gland causing a disruption in the secretion of ADH

Hypopituitarism

Rare disorder that includes conditions that results from the deceased level or absence or pituitary hormones originating from the anterior pituitary gland 

Cushing disease

Results from excess of cortisol production by the adrenal cortex, or excessive use of glucocorticoid hormones 

Adrenal insufficiency

Inadequate secretion of corticosteroids

Addison disease 

Rare disease due to the partial or complete destruction of the adrenal cortex 

Adrenal adenomas

Most common adrenal lesion and are typically an incidental finding during abdominal imaging 

Diabetes 

Group of metabolic diseases characterized by hyperglycemia in combination with glucose intolerance and alterations in the metabolism of carbohydrates, fats, and proteins

Type 1 diabetes mellitus

Caused by an autoimmune reaction that causes the destruction of the b-cells of the pancreas that prevents the body from making insulin 

Type 2 diabetes mellitus

Characterized by high blood glucose levels, either from insulin resistance or inadequate secretion of insulin

Metabolic syndrome

Group of conditions that have been linked to type 2 diabetes mellitus and heart disease 

Gestational diabetes

Type of diabetes due to an insulin resistance that occurs during pregnancy in pts with no prior history of diabetes 

Hyperthyroidism

Increased production and secretion of thyroid hormone from the thyroid gland

Graves disease

Autoimmune disorder where the body creates antibodies that attach to the thyroid TSH receptor and mimics TSH, causing the thyroid gland to secrete excess amounts of TH

Thyrotoxicosis

Hypermetabolic clinical syndrome caused by a pathological excess of circulating T4 and T3

Hypothyroidism

Common clinical syndrome of the thyroid gland that results from inadequate TH production resulting in a decreased rate of cellular metabolism 

Hyperparathyroidism

The effect of excess parathyroid hormone resulting in characteristic skeletal features due to an increase in osteoclastic activity 

Nephrocalcinosis

Condition characterized by tiny deposits of calcium phosphate dispersed throughout the renal parenchyma 

Medical treatment designed to lower serum calcium levels is important in the management of:

Nephrocalcinosis

Osteopenia is a term used to describe the radiographic appearance associated with a decrease in bone density and is associated with:

Osteoporosis 

Metabolic actions of the endocrine system in response to changes in blood chemistry best defines _______ stimuli 

Humoral 

Corticosteroid production occurs in the:

Adrenal cortex

B-cells in the pancreas produce:

Insulin

Acromegaly is a condition resulting from disorder of the _____ gland

Pituitary

Addison disease is associated with the:

Adrenal glands 

Type 2 diabetes mellitus is most common in:

Adults pts