ACTH
What gland does ACTH stimulate?
Adrenal
What gland does TSH stimulate?
Thyroid
What effect does GH have on growth plates?
chondrocyte proliferation
bone growth
What is the primary function of prolactin?
Stimulates milk production in the mammary glands
What organ do LH and FSH act on?
Gonads – testes & ovarie
What hormone does the adrenal cortex release in response to ACTH?
Cortisol
What two thyroid hormones does TSH regulate?
T3 and T4
What organ produces IGF-1 in response to GH?
Liver
What hypothalamic neurotransmitter inhibits prolactin?
Dopamine
What does LH stimulate in males?
Testosterone production via Leydig cells
Which condition results from ACTH deficiency?
Secondary adrenal insufficiency
What happens to TSH levels in primary hypothyroidism?
increase
reason: loss of negative feedback loop
Name one pathological effect of excess GH in adults
Acromegaly
-enlarged facial features, hands, feet
What condition results from excess prolactin secretion?
Hyperprolactinemia – can cause infertility, galactorrhea)
What phase of the menstrual cycle is triggered by an LH surge?
Ovulation
How does ACTH influence aldosterone secretion?
minimal:
RAAS primarily regulates Aldosterone
What antibody is associated with autoimmune hyperthyroidism?
TSH receptor-stimulating antibody, seen in Graves’ disease
How does GH affect glucose metabolism?
increases blood glucose via insulin resistance
How does prolactin influence gonadotropin release?
suppresses GnRH, reducing LH/FSH levels
What type of cells does FSH stimulate in males?
Sertoli cells – supports spermatogenesis
What test is used to diagnose ACTH-dependent Cushing’s Syndrome?
Dexamethasone suppression test
assessing how cortisol levels respond to dexamethasone (Steroid drug)
What feedback mechanism regulates TSH secretion?
Negative feedback from circulating T3/T4 levels
What hypothalamic hormone inhibits GH release?
Somatostatin
What medication class is commonly used to lower prolactin levels?
Dopamine agonists
How does negative feedback from testosterone regulate LH secretion?
Testosterone inhibits GnRH release from the hypothalamus, reducing LH output