Adrenal Glands Flashcards
What type of hormones does the adrenal cortex produce?
Steroid hormones
What type of hormones does the adrenal medulla produce?
Amine hormones
What are the three layers of the adrenal cortex?
Zona glomerulosa, Zona fasciculata, Zona reticularis
What does the zona glomerulosa produce and what is the major hormone secreted?
Mineralcorticoids ; aldosterone
What does the zona fasciculata produce and what is the major hormone secreted?
Glucocorticoids ; cortisol
What does the zona reticularis produce and what is the major hormone secreted?
Sex hormones ; androgens
What is the function of mineralcorticoids?
Regulate salt balance
What is the function of glucocorticoids
Assist with carbohydrate metabolism
Hat is the function of androgens
Required for sexual function but contributes less than the gonads
Function of aldosterone
Controls the amount of fluid in the body.
Increases the salt and water conservation via renal tubular retention of Na, Cl, and H2O and promotes the excretion og K and H. Aldosterone results in vasoconstriction which will increase BP and BV
T/F:
Blood levels are higher in the morning
TRUE
Adrenal Disease
HYPERALDOSTERONISM
- Secreting adrenal adenoma — conn syndrome
- Aldosterone — secreting adrenal carcinoma
- Hyperplasia of adrenal cortex
Reninangiotensin system disorder
HYPERALDOSTERONISM
- excess produciton of renin
- malignant hypertension
- renin secreting renal tumor
List some causes of hypoaldosteronism
- Atrophy of adrenal glands
- Addison’s disease (atrophy with Dec prod of aldosterone and glucocorticoids
- Congenital deficiency of 21-hydroxylase enzyme
What is the feedback look for cortisol production?
Hypothalamus (CRH) -> anterior pituitary (ACTH) -> Cortisol production
Low levels of cortisol ___ the release of ACTH ; high levels of cortisol ___ the release of ACTH
Promote ; Inhibit
Cuse of primary hypercortisolism
adrenal adenoma or carcinoma
Exogenous administration of cortisol
What type of hypercortisolism is Cushing Syndrome and what is it caused by
Primary
Excess cortisol
What causes secondary hypercortisolism
Excessive production of ACTH from pituitary tumor
Ectopic production of ACTH by nonendocrine tumor
What type of hypercortisolism is Cushing Disease and what is it caused by
Secondary
Pituitary ACTH excess which stimulates excess cortisol production
What are the cases of primary hypocortisolism
Atrophy of adrenal gland
Autoimmune disease
TB
Prolonged high dosage cortisol therapy
What is the cause of secondary hypocortisolism
Pituitary hypofunction
List the catecholamines
Epinephrine (EPI)
Norepinephrine (NE)
Dopamine
Where are catecholamines produced?
Tyrosine cells of the medulla, brain, and sympathetic neurons
Function of epinephrine
Converts glycogen to glucose
Released in response to low BP, hypoxia, cold exposure, muscle exertion, and pain
Function of norepinephrine
Neurotransmitter affecting vascular smooth muscle and heart
Released primarily by the postganglionic sympathetic nerves
Function of dopamine
Neurotransmitter in the brain affecting the vascular system
Catecholamine metabolism of DOPAMINE
Dopamine > homovanillic acid
Catecholamine metabolism of NOREPINEPHRINE
Norepinephrine > normetanephrine > vanillylmandelic acid
Catecholamine metabolism of EPINEPHRINE
Epinephrine > metanephrine > vanillylmandelic acid
What is a pheochromocytoma
tumor of the adrenal medulla, usually benign
What does a pheochromocytoma cause
INC EPI and NE
What is a neuroblastoma
Malignant tumor of the adrenal medulla that occurs in children
What does a neuroblastoma cause
Produces EPI, NE, and dopamine. Causes INC HVA and VMA in urinary excretion
What are clinical features of pheochromocytoma
HTN, paroxysomal with spells of sweating, hyperaldosteronism, or palpitations
What are clinical features of Cushing’s syndrome
HTN, obesity, weakness
What are clinical features of Primary aldosteronism
HTN, hypokalemia, weakness
What are clinical features of adrenocarcinoma
Virilization, HTN, weakness
Testes are part of the ____-____-____ axis
Hypothalamic - pituitary - gonadal axis
LH and FSH are produced by what
Anterior pituitary
Function of LH in regards to the testes
stimulates production of testosterone
Function of FSH in regards to the testes
stimulates spermatogenesis
What controls LH and FSH?
GnRH
What type of feedback loop is LH and FSH
Negative
What defines a primary disorder for abnormal synthesis of testosterone
Caused by the testes
What defines a secondary disorder for abnormal synthesis of testosterone
due to primary disorder of the pituitary or hypothalamus
Function of testosterone
Responsible for development and maintenance of secondary male sex characteristics
Hyperandrogenemia is observed in what populations
adult males, prepubertal males (precocious puberty), and female children
What causes congenital adrenal hyperplasia
Enzyme defect of 21-hydroxylase
What is observed in congenital adrenal hyperplasia
Prevents cortisol production and causes the accumulation of cortisol precursors such as 17-OHP
INC blood 17-OHP and ACTH
DEC blood cortisol
Consequences of hypoandrogenemia in adult males
Impotence
Loss of secondary sex characteristics
Consequences of hypoandrogenemia in prepubertal males
delayed puberty
Causes of primary hypoandrogenemia
Tumors, infections, congenital disorders
Example of primary hypoandrogenemia
Klinefelter syndrome
Causes of secondary hypoandrogenemia
primary hypofunction disorders of the pituitary or hypothalamus
What is observed in secondary hypoandrogenemia
DEC synthesis of LH and FSH
What is the chromosomal abnormality observed in Klinefelter Syndrome
XXY
Within what time frame should a semen analysis be performed
within 30 minutes
What are the components of a semen analysis
pH
Motility
Sperm Count
Sperm Quality (morphology and viability)
What axis are the ovaries a part of?
Hypothalamic - pituitary - gonadal axis
Function of LH in regards to the ovaries
Stimulates the production of progesterone at ovulation
Function of FSH in regards to the ovaries
Stimulates the growth of the ovarian follicles and increases the plasma estrogen level
What are the principle female sex hormones
Estrogen and progesterone
What are the three primary estrogens
Estradiol 17b, estrone, estradiol
What is the principle estrogen produced by the ovaries
Estradiol
What is estrogen secreted by
ovarian follicles and the placenta during pregnancy (lesser the adrenal glands and testes)
What is progesterone secreted by
Ovarian follicles and mainly the corpus luteum following ovulation. Also by the placenta during pregnancy
Function of estrogen
Promotes development and maintains the female reproductive system.
Responsible for the development and maintenance of secondary female sex characteristics
Function of progesterone
In pregnancy, secreted by the placenta to maintain the uterus
Describe the hormone levels of the anterior pituitary during the menstrual cycle
FSH is typically at higher concentrations then LH and both peak at 14 days during ovulation
Describe the hormone levels of the ovariesduring the menstrual cycle
Before ovulation at 14 days, estrogen continues to rise and is at the highest concentration over progesterone and testosterone. It peks at 14 days, drops, and rises and falls in a bell curve with the next peak (not as high as the first) during the luteal phase
Progesterone steadily climbs and then climbs dramatically after ovulation and peaks during the luteal phase above estrogen. Levels fall back to below estrogen at the 28 day mark
Testosterone is in the lowest concentration during the entirety but has a small peak at 14 days
Hyperestrinism in females results in
Precocious puberty
Infertility and irregular menses
Postmenopausal bleeding
Hyperestrinism in males results in what
Testicular atrophy and enlargement of breasts
Hypoestrinism in females results in
Ovarian insufficiency
Delayed puberty
Amenorrhea
Tuner Syndrome (genetic defect in females, loss of one or two X chromosomes)
What is the consequencial difference between hyperprogesteronemia and hypoprogesteronemia
HYPERprogesteronemia: prevents menstrual cycle from occuring
HYPOprogesteronemia: causes infertility, abortion of fetus
What is Polycystic Ovary Syndrome
Many cysts in the ovaries
Infertility, hirsutism, chronic anovulation, glucose intolerance, hyperlipidemia, dyslipidemia, hypertension
What is hirsutism
Abnormal, abundant, androgen sensitive terminal hair growth in areas which terminal hair follicles are sparsely distributed
Causes of infertility in females for the following
Hypothalamus:
Pituitary:
Ovaries:
Fallopian Tubes and Uterus:
Conception:
Hypothalamus: drugs, INC stress, diet = DEC GnRH
Pituitary: Tumor or vesicular lesion = DEC FSH and LH
Ovaries: Organ failure, organ dysgensis, antiovarian ab, malnourishment = DEC Estradiol and Progesterone
Fallopian Tubes and Uterus: low progesterone output = inadequate endometrium // pelvic inflammation disease = tubal scarring and closure // cervical infections = DEC cervical mucus
Conception: Antisperm ab = immobilization and destruction of sperm
Causes of infertility in males for the following
Hypothalamus and Pituitary:
Testes:
Prostate:
Urethrogenetial tract:
Hypothalamus and Pituitary: primary defects in hypothalamus or pituitary glands, exogenous androgens, testicular dysfunction = oligospermia to azoospermia
Testes: orchitis = oligospermia to azoospermia // testicular infections = delayed or deficient sexual maturity // alcoholism or substance abuse = DEC testosterone
Prostate: infections of prostate or seminal vesicles = DEC seminal fluid
Urethrogenetial tract: Physical abnormalities and chronic diabetes = retrograde or absent ejaculation
