Hormones Flashcards
Neuroendocrine cells
In hypothalamus.
Neurons that secrete hormones to bloodstream at axons instead of neurotransmitters.
Three types of hormones
Peptides (amino acid chain), amine, steroids.
Peptide/amine hormones
Bind to receptors outside cell, activate second messengers (cAMP)
Act faster than steroids.
Peptide example: ACTH, insulin.
Amino acids: epinephrine, NE, TSH
Steroid hormones
Pass thru the membrane and acts as TF binds to DNA. Can have steroid receptor cofactors. Sex hormones (estrogens, progestins) and stress hormones (glucocorticoids)
Posterior pituitary
Aka neurohyphysis.
Contains axons.
Secretes oxytocin and vasopressin (ADH)
Anterior pituitary
Adrenohyphysis. Made of primarily blood vessels. Under control of hypothalamus. Release/synthesis of tropic hormones. Uses hypophyseal portal system to dump hormones into.
6 tropic hormones released by anterior pituitary
ACTH - daily rhythm (adrenocorticotropic hormone)
TSH- thyroid stimulating hormone
Gonadotropins- FSH and LH
GH (growth hormone)
Prolactin- stim milk production and parental behavior.
Hormones in gonads (male)
GnRH (stim by kisspeptin) and GnIH from hypothalamus (gonadotropins influence)
Sertoli- produce sperm
Leydig- testosterone- secondary sex characteristics, emotion/mood.
Hormones in gonads (female)
Gonadotropins activate progestins (controls lining of uterus, less = shedding of lining)
Estrogens (cognition, masculinized brain, protect women from stroke/stress)
Pineal gland
Produced melatonin (monoamine) Related to rhythms
Adrenal cortex hormones
Mineralocorticoids (regulate Na+ and water, e.g. Aldosterone) and glucocorticoids (decrease inflammation, narrow cognition during stress e.g. Cortisol)
Adrenal medulla
Secretes NE and Epi (slower response than nervous system and longer acting)
Adrenal gland
Responds to ACTH from pituitary. Pituitary responses to CRH from hypothalamus.
