Thyroid, Parathyroid, Adrenal, and Pineal Glands

4

Thyroid gland:

- T.... is the inactive thyroid hormone

3

Thyroid gland:

- T.... is the active thyroid hormone

TBG (thyroid-binding globulin)

Thyroid gland:

- Most T3 and T4 are bound to .... and are hence inactive

4

Thyroid gland:

- T.... is produced in larger amounts (80-90%)

free thyroxine

Thyroid gland:

- only ..... enters the cells

primary

which form of hyperthyroidism:

- Problem with thyroid gland -> increase T3/T4 -> feedback decrease TSH

secondary

which form of hyperthyroidism:

- Problem with pituitary gland -> increase TSH -> increase T3/T4

thyroid

Thyroid gland:

- primary hyperthyroidism is associated with problems of the ... gland

pituitary

Thyroid gland:

- secondary hyperthyroidism is associated with problems of the ... gland

hyper

.....thryroidism is associated with:

- heat intolerance

- irritability

- excess sweating

- exophthalmos

- weight loss

graves disease

Thyroid gland:

- Thyroid disease of autoimmune origin.

- Hyperthyroidism results from circulation of antibodies known as TSIs

Symptoms:

- insomnia

- tremor

- sweating

- weight loss

- goiter

- sensitivity to heat

Diagnosis

- test TSH levels

- serology for TSI

Treatment:

- propranolol to control symptoms

- antithyroid drugs

- radioiodine ablation

primary

which form of hypothyroidism:

- Decreased thyroid hormone due to decreased production by the thyroid

- high TSH, low T3 and T4

Causes:

- Hashimoto’s thyroiditis

- Drug-induced hypothyroidism

- Status post radioactive iodine (RAI) ablation therapy

- Iodine deficiency

secondary

which form of hypothyroidism:

- Decreased thyroid hormone due to decreased TSH

Causes:

- Tumor

- mass effect

tertiary

which form of hypothyroidism:

- Decreased thyroid hormone due to decreased TRH

hypo

.....thryroidism is associated with:

- bradycardia

- cold intolerance

- hair loss

- hoarseness

- weight gain

hashimotos thyroiditis

Thyroid gland:

- autoimmune disorder

- causes hypothyroidism

- increases risk of non-hodgkin lymphoma

congenital hypothyroidism

Thyroid gland:

- severe fetal hypothyroidism

- presents with the 6 P's

- No amount of thyroid hormone replacement therapy will restore normal mental development if thyroid hormone is lacking in the first 6 months after birth

- causes cretinism

iodine deficiency

Thyroid gland:

- causes hypothyroidism

- causes a large goiter

chief

parathyroid gland:

- The glands are richly vascularized and consist primarily of ..... cells

-have a thin capsule of connective tissue that divides the gland into lobules

bone; calcium

parathyroid gland:

- chief cells synthesize PTH

- PTH plays a major role in .... remodeling and .... homeostasis

increases; decreases

parathyroid gland:

- PTH ..... serum calcium and .... serum phosphate

primary

which form a hyperparathyroidism:

- excess secretion of PTH

- normal feedback mechanism fails to inhibit PTH secretion

- results in hypercalcemia and hypophosphatemia

Causes:

- parathyroid tumor

Treatment:

- surgery

secondary

which form a hyperparathyroidism:

- body tries to react to hypocalcemia by increasing the release of PTH.

Causes:

- chronic renal disease

- Vitamin D deficiency

Treatment:

- manage underlying cause

hyper

.....parathryroidism is associated with:

- Fragile bones

- Kidney stones

- abdominal pain

- depression or forgetfulness

- frequent complaints of illness with no apparent cause

thyroid

parathyroid gland:

- hypoparathyroidism is most commonly caused by damage to the parathyroid glands during ... surgery

decreased; increased

parathyroid gland:

- hypoparathyroidism causes .... serum calcium and .... serum phosphate

hypo

.....parathryroidism is associated with:

- related to hypocalcemia

- lower threshold for nerve and muscle excitation

- chvostek and trousseau signs

chvosteks

parathyroid gland:

- .... sign is twitching of upper lip after tapping on the cheek and is a sign of hypoparathyroidism

trousseaus

parathyroid gland:

- .... sign is pressure on upper arm causing a closure of the hand and is a sign of hypoparathyroidism

glomerulosa

adrenal gland:

- the zona .... the outermost layer of the adrenal cortex regulates salt levels

Main hormone:

- Aldosterone (a mineralocorticoid)

General function:

- Maintain blood electrolyte balance

Main control:

- Angiotensin II, K+

fasciculata

adrenal gland:

- the zona .... the middle layer of the adrenal cortex regulates sugar levels

Main hormone:

- Cortisol

General function:

- Includes regulating glucose and fatty acid metabolism, and response to stress

Main control:

- Pituitary ACTH, stress

reticularis

adrenal gland:

- the zona .... the inner layer of the adrenal cortex and regulates sex

Main hormone:

- Dehydroepiandrosterone

General function:

- ZR begins to appear after birth at about 5 years of age.

- Adrenal androgens contribute to the appearance of axillary and pubic hair at about age 8.

- DHEAS levels continue to increase, peak during the mid-twenties, and then progressively decline with age.

Main control:

- Pituitary ACTH

medulla

adrenal gland:

- the adrenal ... is the inside of the adrenal gland and regulates fight or flight

reabsorption; secretion

adrenal gland:

- Aldosterone promotes the ..... of Na+ and the .... of K+

metabolic alkalosis

adrenal gland:

- aldosterone increases H+ secretion and increases HCO3- production which causes ....

primary

which form of hyperaldosteronism:

- Excessive secretion of aldosterone due to adenoma of the adrenal cortex

- results in increased ECF, hypertension, metabolic alkalosis

- associated with Conn Syndrome

secondary

which form of hyperaldosteronism:

- Excessive secretion of aldosterone from an extra-adrenal stimulus

- Most often due to high levels of angiotensin II through a renin-dependent mechanism.

renin

adrenal gland:

- elevated plasma .... levels differentiate between primary and secondary hyperaldosteronism

cholesterol

adrenal gland:

- cortisol is synthesized from ..... in cells of the zona fasciculata of the adrenal cortex

ACTH

adrenal gland:

- cortisol is released under the influence of ....

lowest; highest

adrenal gland:

- cortisol levels are the .... after falling asleep and the .... just before awakening

increases

adrenal gland:

- cortisol .... blood sugar levels

anti; increases

adrenal gland:

- cortisol has ....inflammatory effects and therefor its deficiency ... the risk of infection and poor wound healing

primary

which form of adrenocortical hypofunction:

- Inability to produce and secrete adrenal hormones

- associated with Addison disease

secondary

which form of adrenocortical hypofunction:

- Inadequate stimulation of the adrenal glands by ACTH

tertiary

which form of adrenocortical hypofunction:

- Abrupt withdrawal from high endogenous or exogenous cortisol levels

addison disease

adrenal gland:

- all layers of adrenal cortex destroyed due to autoimmune disease

- more common in women

- may cause Addisonian Crisis: Collapse in a patients caused by adrenal insufficiency, triggered by general anesthesia, trauma, infections, or other stress

cushing syndrome

adrenal gland:

- Persistently increased adrenal cortex production of hormones, especially cortisol and androgens

Causes:

- pituitary microadenoma that increases production of ACTH

epinephrine; norepinephrine

adrenal gland:

- two main catecholamines produced by the adrenal medulla are ..... and .....

respiratory system

epinephrines effect on the .....:

• Increases dilation of the bronchi and bronchioles

• Increases respiratory rate

GI tract

epinephrines effect on the .....:

• Inhibition of peristalsis, relaxation of gut smooth muscle

• contraction of gut sphincters

• Vasoconstriction of gut vasculature.

metabolism

epinephrines effect on .....:

• In the liver: promotes glycogenolysis, gluconeogenesis, release of glucose into the circulation.

• In skeletal muscle: promotes glycogenolysis and lactic acid formation.

• In fat: stimulates lipolysis to release free fatty acids and glycerol.

CNS

epinephrines effect on the .....:

- Causes arousal via actions in the brainstem and produces coarse tremors

pheochromocytoma

adrenal gland:

- tumor of the adrenal medulla

eyes

pineal gland:

- stimulated by nerves from the ....

melatonin

pineal gland:

- functions to produce ....

SAD

pineal gland:

- Caused when too much melatonin is produced, especially during the long nights of winter, causing profound depression, oversleeping, weight gain, tiredness, or sadness

- Treatment consists of exposure to bright lights for several hours each day to inhibit melatonin production