Endocrine Flashcards
cAMP hormones
FSH, LH, ACTH, TSH (all ant. pit) FLAT
and also hcG
MSH
GHRH
CRH
PTH
Calcitonin
Glucagon
V2 vasopressin receptor
Gq Inositol triphosphate (IP3) pathway
hypothalamic hormones
GnRH
TRH- thyrotropin releasing hormone
post pit:
Oxytocin
Vasopressin at the V1 receptor
Tyrosine kinase receptor
growth factors growth hormone (GH) prolactin insulin insulin-like growth factor (IGF1) platelet- derived growth factor (PDGF) fibroblast growth factor (FGF) cytokines
cGMP
nitric oxide (NO) antrial natriuretic peptide (ANP)
these both act to vasodilate
steroid receptors
estrogens, progesterones, testosterone glucocorticoids aldosterone thyroid hormone vitamin D
- intracellular
- gene transcription
these receptors are found intracellularly. When bound, the receptor undergoes coformational change whereby DNA- binding domain is exposed. This leads to binding of a gene enhancer region
stimulates bone and muscle growth
growth hormone via insulin like growth factor (IGF1), which stimulates TKR
stimulates milk production
prolactin
stimulates milk secretion during lactation
oxytocin
responsible for female secondary sex characteristics
estradiol
stimulates metabolic activity
T4, T3
increases blood glucose level and decreases protein synthesis
glucacorticoids
responsible for male secondary sex characteristics
testosterone
prepares endometrium for implantation/ maintenance of pregnancy
progesterone
stimulates adrenal cortex to synthesize and secrete cortisol
ACTH- adrenocorticotropic hormone
stimulates follicle maturation in females and spermatogenesis in males
follicle stimulating hormone
increases plasma calcium, increases bone resorption
parathyroid hormone
decreases plasma calcium, increases bone formation
calcitonin
stimulates ovulation in females and testosterone synthesis in males
luteinizing hormone
stimulates the thyroid to produce TH and uptake iodine
thyroid stimulating hormone
where does growth hormone come from?
anterior pituitary
where does thyroid hormone come from?
thyroid
glucocorticoids
adrenal cortex (zona fasciculata)
progesterone
ovaries, and placenta if there is one
prolactin
anterior pituitary
oxytocin
hypothalamus (paraventricular nucleus)
atrial natriuretic hormone
atria of the heart
glucagon
alpha cells of the pancreas
testosterone
testes (men) ovaries (women), and in a small amount, in the zona reticularis of the adrenal cortex
vasopressin (ADH)
posterior pituitary for storage, ,made in the hypothalamus (supraoptic nucleus)
calcitonin
parafollicular cells of the thyroid
thyroid stimulating hormone (TSH)
anterior pituitary
epinephrine and norepinephrine
chromaffin cells of the adrenal medulla
insulin
beta cells of the pancreas
estradiol
ovaries
estriol
placenta
estrone
fat cells
estrogen in males
testes
PTH
parathyroid glands
somatostatin
delta cells of pancreas
luteinizing hormone (LH)
anterior pituitary
mineralocorticoids (aldosterone)
zona glomerulosa
adrenocorticotropic hormone (ACTH)
anterior pituitary
androgen binding protein
binds testosterone
embryological origins of anterior pituitary
Rathke’s pouch (ectodermal diverticulum)
embryological origins of posterior pituitary
invagination of hypothalamus (neuroectoderm)
2 proteins produced in the hypothalamus and stored in the posterior pituitary
oxytocin, ADH
ADH
antidiuresis by increasing water reuptake in the DCT of the kidney
more ADH for concentrate urine in small amounts
ADH promotes vascular constriction
this is why and how vasopressin can be used to stimulate an increase in BP
how do nicotine and opiates affect ADH levels?
increase (less urine)
how do decreased serum osmolarity, ethanol and atrial natriuretic factor affect ADH?
They decrease ADH, promoting diuresis
oxytocin
pregnancy breastfeeding hormone
causes uterine contractions, important for delivering baby as well as for stopping bleeding afterwards.
oxytocin release is stimulated by uterine dilation during labor
stimulates milk ejection from the breast, upon suckling
this is inhibited by alcohol and stress
anterior pituitary hormones
stimulated by upstream hormones, and have downstream targets at various glands. middle men
pulsatile release of GnRH–>
pulsatile release of FSH –> gonads
constant GnRH inhibits LH and FSH release
GnRH--> LH --> gonads ACTH TSH Prolactin Intermediate- MSH GH
inhibin
inhibits FSH
progesterone and testosterone affects on LH
inhibition
four hormones that share a common alpha subunit
LH, FSH, TSH, hCG
ACTH
stimulated by CRH from the hypothalamus, and stress
ACTH induces cortisol production at the adrenal gland, which has a negative feedback effect on ACTH
MSH
anterior pituitary, stimulates melanocytes of skin
ACTH, MSH, and proopiomelanocortin (PMC)
ACTH is synthesized as part of a large precursor called POMC.
POMC contains sequences for other hormonal peptides including lipotropin, MSH, beta-endorphin
When ACTH is in excess, it stimulates MSH receptors, leading to hyperpigmentation in for example, Addison disease
TSH
stimulated by thyroid releasing hormone from the hypothalamus
it in turn, stimulates thyroid hormone production and secretion from the downstream thyroid gland
T3 and T4 will directly inhibit TSH secretion
Growth hormone (somatotropin)
helps grow, decreases glucose uptake, increases protein synthesis, increases organ size and lean body mass
increased by growth hormone releasing hormone (GHRH)
and inhibited by growth hormone inhibiting hormone (GHIH), aka somatostatin
downstream hormone (rather than gland) is IGF1, or insulin growth factor 1, which stimulates growth in peripheral tissues
things that stimulate growth hormone release
GHRH, exercise, sleepp, puberty, hypoglycemia, estrogen, stress, endogenous opioids
things that inhibit growth hormone release
somatostatin somatomedins obesity pregnancy hyperglycemia
prolactin functions
stimulates breast development inhibits ovulation (inhibits GnRH, which inhibits release of FSH, LH, and thereby decreases the likeliihood of pregnancy while breast feeding)
what hormone stimulates prolactin release?
thyrotropin releasing hormone