[09.05] Principles of Hormonal Testing V2

70 percent

What percentage of a suspected diagnosis does the clinical history usually account for?

20 percent

What percentage of a suspected diagnosis does the physical examination account for?

10 percent

What percentage of a suspected diagnosis do laboratory and imaging findings account for?

Hormonal testing

What is considered the backbone of endocrinology?

Subtle signs and symptoms

Why do many endocrine disorders require screening even in people without symptoms?

50 to 60 percent

What percentage of individuals with Type 2 Diabetes are asymptomatic at diagnosis?

35

At what age should screening for diabetes begin for individuals with average risk?

Earlier than age 35

When should screening for diabetes begin for individuals with higher risk factors?

Confirm the diagnosis

What is the purpose of requesting thyroid function tests for a patient presenting with weight loss and heat intolerance?

TSH, T3, and T4

Which three tests are requested to confirm suspected hyperthyroidism?

Monitor disease status or progression

Why are serial TSH measurements performed after surgery and radioactive iodine ablation for thyroid carcinoma?

TSH suppression goal

What is measured to determine if treatment has been successful in preventing thyroid cancer recurrence?

Dynamic testing

What type of testing is used when evaluation of hormonal excess or deficiency is difficult without an external stimulus?

Radiologic imaging

What should only be performed after a hormonal abnormality has been established?

Hypothalamus

Which gland produces Thyrotropin-releasing Hormone TRH?

TSH and Prolactin

Which two hormones are stimulated for secretion by TRH?

Corticotropin-releasing hormone CRH

Which hypothalamic hormone stimulates the secretion of ACTH from the anterior pituitary?

Growth Hormone-releasing hormone GHRH

Which hormone stimulates the secretion of Growth Hormone from the anterior pituitary?

Somatostatin

What is the main inhibitory hormone for Growth Hormone release?

Body

What does the prefix somato mean?

Hold something

What does the suffix statin mean?

Gonadotropin-releasing hormone GnRH

Which hormone stimulates the secretion of FSH and LH?

Dopamine

What is the main hormone that inhibits the secretion of prolactin?

Prolactin-Inhibiting Factor PIF

What is another name for dopamine in the context of pituitary regulation?

Growth Hormone GH

Which hormone stimulates protein synthesis and overall growth of most cells?

Adolescence and early adulthood

When does Growth Hormone secretion peak?

Thyroid-Stimulating Hormone TSH

Which hormone stimulates the synthesis and secretion of triiodothyronine and thyroxine?

T3 and T4

What are the shorthand names for the two primary thyroid hormones?

Adrenocorticotropic Hormone ACTH

Which hormone stimulates the secretion of cortisol, androgens, and aldosterone?

Prolactin

Which hormone promotes female breast development and milk secretion?

TRH

Besides inhibiting dopamine, what hormone from the hypothalamus can stimulate Prolactin?

Follicle-Stimulating Hormone FSH

Which hormone causes follicle growth in ovaries and sperm maturation in testes?

Luteinizing hormone LH

Which hormone stimulates testosterone synthesis in Leydig cells?

LH

Which hormone stimulates ovulation and the formation of the corpus luteum?

Hypothalamus

Where are the hormones released by the posterior pituitary actually produced?

Stalk extension

What is the physical relationship between the hypothalamus and the posterior pituitary?

Antidiuretic Hormone ADH

Which hormone increases water reabsorption by the kidneys and causes vasoconstriction?

Vasopressin

What is another name for ADH?

Anti-diuresis

What term describes the process of reabsorbing water rather than releasing it?

Oxytocin

Which hormone stimulates milk ejection from breasts and uterine contractions?

Increase metabolic rate

What is the primary function of T3 and T4?

Calcitonin

Which hormone promotes the deposition of calcium in bones?

C cells

Which specific cells in the thyroid gland produce calcitonin?

Decreases calcium concentration

What is the effect of calcitonin on extracellular fluid calcium?

Cortisol

Which adrenal cortex hormone has anti-inflammatory effects and controls the metabolism of proteins, carbs, and fats?

Aldosterone

Which hormone increases renal sodium reabsorption and potassium secretion?

DHEA

Which androgen is primarily secreted by the adrenal cortex?

Adrenal medulla

Which part of the adrenal gland secretes norepinephrine and epinephrine?

Sympathetic stimulation

The effects of norepinephrine and epinephrine are the same as what type of nervous system response?

Insulin

Which pancreatic hormone promotes glucose entry into cells?

Beta cells

Which specific pancreatic cells produce insulin?

Glycogenesis and proteogenesis

What two anabolic processes are promoted by insulin?

Glucagon

Which pancreatic hormone increases the synthesis and release of glucose from the liver?

Alpha cells

Which specific pancreatic cells produce glucagon?

Glycogenolysis, gluconeogenesis, and proteolysis

What three catabolic processes are promoted by glucagon?

New sugar formation from non-carbohydrate sources

What is the definition of gluconeogenesis?

Parathyroid hormone PTH

Which hormone controls serum calcium by increasing absorption and releasing it from bones?

Deposits calcium in bones

What is the function of Calcitonin compared to PTH?

Releases calcium from bones

What is the function of PTH compared to Calcitonin?

Testosterone

Which hormone promotes the development of the male reproductive system and secondary sexual characteristics?

Estrogens

Which hormone promotes the development of the female reproductive system and breasts?

Progesterone

Which hormone stimulates the secretion of uterine milk and develops the breast secretory apparatus?

Human chorionic gonadotropin hCG

Which placental hormone promotes the growth of the corpus luteum?

Human somatomammotropin

Which placental hormone helps develop fetal tissues and the mother's breasts?

Renin

Which kidney enzyme catalyzes the conversion of angiotensinogen to angiotensin I?

1,25-Dihydroxycholecalciferol

Which kidney hormone increases intestinal calcium absorption and bone mineralization?

Erythropoietin

Which hormone increases erythrocyte production?

Atrial natriuretic peptide

Which heart hormone increases sodium excretion and reduces blood pressure?

Gastrin

Which stomach hormone stimulates hydrogen chloride secretion by parietal cells?

Secretin

Which intestinal hormone stimulates pancreatic acinar cells to release bicarbonate?

Cholecystokinin

Which hormone stimulates gallbladder contraction and pancreatic enzyme release?

Leptin

Which adipocyte hormone inhibits appetite and stimulates thermogenesis?

Adiponectin and Resistin

Name two other hormones secreted by adipose tissue.

Feedback regulation

What is described as the seesaw of hormone levels?

Hypothalamus

Which brain region acts as the control center for releasing hormones?

Stress

In response to what stimulus does the hypothalamus release CRH?

Sella turcica at the base of the brain

Where is the pituitary gland located?

Adrenal glands

Which glands are situated on top of the kidneys?

Positive feedback

In the HPA axis, what kind of feedback do CRH and ACTH provide for cortisol?

Negative feedback

What occurs when cortisol levels are high enough?

TRH

What hormone initiates the HPT axis?

Negative feedback

In the HPT axis, what do high T4 and T3 levels exert on the hypothalamus and pituitary?

Primary hyperthyroidism

If T4 and T3 are high and TSH is low, what is the diagnosis?

Graves disease

What is a common cause of primary hyperthyroidism?

Secondary hyperthyroidism

If TSH is high and T4/T3 are also high, what is the diagnosis?

Luteal phase

During which part of the menstrual cycle do estrogen and progesterone exert strong negative feedback?

Corpus luteum

What structure secretes high levels of estrogen and progesterone during the luteal phase?

Follicular phase

Which phase of the menstrual cycle involves the buildup of follicles until ovulation?

GnRH

Which hormone initiates both the male and female HPG axes?

Leydig cell

Which cell in the testes releases testosterone in response to LH?

Sertoli cell

Which cell in the testes makes inhibin in response to FSH?

Inhibin

Which hormone indirectly inhibits FSH secretion through deactivation of activin?

Spermatogenesis

What is the main process stimulated by FSH in males?

Negative feedback

What does elevated testosterone exert on the hypothalamus?

FSH production

In both males and females, what specific hormone is inhibited by inhibin?

Sympathetic response

The Renin-Angiotensin System is the main hormonal secretion during what type of response?

Endocrine hypertension

Uncontrolled hypertension may warrant checking for what condition?

Angiotensin I

Renin converts angiotensinogen into what substance?

ACE

Which enzyme catalyzes the conversion of angiotensin I to angiotensin II?

Vasoconstriction

What is the primary action of angiotensin II on blood vessels?