AKA – insulin-like growth factors (IGF’s); mediate GH actions on DNA and
protein synthesis; act directly on bone, muscle and other tissues
Somatomedins
secretes GRH after being acted on by NT’s
Arcuate Nucleus
found in neck, below larynx; consists of (2) lobes on either side of trachea;
arranged into follicles (closed hollow balls) filled w/ colloid containing thyroglobulin; rich blood
supply; made of cuboidal epithelial cells; flat if inactive
Thyroid Gland
T3; active form; converted from T4 by target cells; binds to the thyroid hormone
receptor
Triiodothyronine
T4; inactive form; accounts for 93% produced and circulated; converted to T3 by target
cells
Thyroxin
hormone secreted by thyroid gland involved in Ca+ homeostasis
Calcitonin
condition seen w/ hypothyroidism in which bone growth is retarded more than soft
tissues; characterized by impaired mental fxn
Cretinism
condition seen w/ hypothyroidism in which the face swells due to increased fluid
retention
Myxedema
condition seen w/ Graves disease or hyperthyroidism characterized by bulging eyes
Exopthalamus
– hormone produced by hypothalamus; responsible for
releasing Prolactin during lactation; responds to signals about body & environmental temp or
excitement and stress
Thyrotrophin Releasing Hormone (TRH)
goitergenic substance responsible for blocks iodine uptake
Thiocyanate
goitergenic substance responsible for blocks oxidation of iodine
Propylthiouracil
Dehydroepiandrosterone (DHEA)
responsible for placenta production of estorgens during
preganancy & stimulation of embryonic & fetal growth during prenatal & early postenatal
development; possible youth hormone – production declines w/ age; stimulates growth of some
cancers and inhibits growth of others
innermost region of adrenal cortex during pregnancy; produces
DHEA
Temporary Fetal Adrenal Zone
produces aldosterone; controlled by the renin-angiostensin system & K+ levels
in ECF; fxn controlled by Corticotrophin (ACTH)
Zona Glomerulosa
controls fxn of zona glomerulosa; DOES NOT stimulate
aldosterone secretion
Corticotrohin – AKA – ACTH
produce glucocorticoids & androgens; controlled by ACTH
Zona Fasciculata & Zona Reticularis
4-ring, 18-21 carbon structure; synthesized from cholesterol; regulated by
ACTH/LH stimulation of cAMP production
Steroid Hormone
21-carbon structure; active form of steroid hormone
Progestin
inactive precursor of steroid hormone; 1st product of cholesterol
Pregnenolone
secreted by ovaries & placenta; promotes body changes to support pregnancy; can
mimic or antagonize actions of adrenal steroid hormones
Progesterone
responsible for glucocorticoid & mineralcorticoid activity; occurs ONLY in zona
reticularis & fasciculata
Cortisol
responsible for minearlcorticoid activity; occurs ONLY in zona glomerulosa
Aldosterone
AKA – Testosterone; 19-carbon structure; masculizing hormone; occurs ONLY in zona
reticularis & fasciculata
Androgen
AKA – 17-beta Estradiol; 18-carbon structure; feminizing hormone
Estrogen
4-ring, 27-carbon structure; precursor for steroid hormones; brought to cells from the
liver via LDL or made by cells from acetate
Cholesterol
– rate limiting step for ALL steroid hormone production
Cholesterol Side Chain Cleavage
genetic mutation resulting in a defective enzyme for cortisol production
Adrenogenital Syndrome
specific binding protein for adrenalcorticoids; produced by liver
Transcotin
major blood protein; non-specific binding protein for ALL steroids; produced by liver
Albumin
transports sex steroids; produced by liver
Sex Steroid Binding Globulin
results from a aldosterone, H+ excretion, & pH
Alkalosis
– results from a aldosterone and pH
acidosis
results from a decrease in ECF; dehydration; low b.p.
Hyponatremia
Hyperkalemia
results from retaining too much K+ in ECF; leads to weakening of the heart, cardiac
arrhythmia, CO, circulatory shock, and finally DEATH
occurs when b.p. increases above 15-25 mmHg and stimulates Na+ & H2O
excretion; protects the body from further rises in b.p. due to aldosterone escape
Pressure Diruesis
uncontrolled aldosterone
aldosterone escape
results from a loss of K+; causes severe skeletal muscle weakness
Hypokalemia
– hormone that acts on the adrenals to stimulate aldosterone production & secretion;
acts on vascular smooth muscle contraction to increase b.p.
Angiotensin II
secrete rennin
JG Cells
secreted by JG cells by the kidney
Renin
– results from elevated blood Glu usually 50% above normal Glu levels
Adrenal Diabetes
– stimulated by anterior pituitary to release ACTH, alpha & gamma MSH,
beta Endorphin, & Lipotrophin
Pro-opiomelanocorti