Endocrine Flashcards
how does the endocrine system message a target tissue
by sending hormones through the blood and connective tissue spaces
how does the nervous system message a target tissue
by the release of neurotransmitters and by the transmission of neural impulses along nerve cell processes
what is the speed and affect of the endocrine system response as compared to the nervous system response
allow, prolonged affect
what traits do all endocrine glands have in common
they do not have excretory ducts
hormone secretions are carried through an extracellular matrix of connective tissue and blood vessels
endocrine glands typically are aggregates of epithelioid cells or cells that lack a free surface, which are embedded with the connective tissues
the secretory products of endocrine glands influence target organs or tissues at some distance from the gland
endocrine glands are well vascularized and surrounded by rich vascular networks
most endocrine cells are derived from what cell origin
epithelial cells
what endocrine cells are of mesenchymal origin
cortex cells of adrenal gland
leydig cells of testis
steroid-secreting cells of the developing follicles in the ovary
what type of cell signaling is associated with the release of hormones that act on adjacent or nearby target cells in the connective tissue matrix
paracrine signaling
what type of cell signaling is associated with a cell targeting itself, and the screwed hormone binding to a receptor on its own surface
autocrine signaling
what are the three major classes of hormones
peptides
steroids
amino acids
what is the largest class of hormones of the three major classes
peptides
by what method does a peptide hormone enter a cell
hormone has to bind to specific receptor proteins because they cannot pass the cell membrane
a second messenger is needed to activate an enzyme or protein synthesis
describe the effects of a peptide hormone
fast acting and transient
what type of protein within the cytoplasm protects a steroid hormone from degradation
carrier proteins
which hormones are examples of peptide hormones
insulin
glucagon
growth hormone
adrenocorticotropic hormone
follicle-stimulating hormone
luteinizing hormone
antidiuretic hormone
oxytocin
interleukins
various growth factors
what three endocrine organs secrete steroid hormones
ovaries
testes
adrenal cortex
what are the five examples of steroid hormones
cortisol
estrogen
progesterone
aldosterone
testosterone
what is the expected rate of onset and lasting effect of steroid hormones
they have a slower onset than other hormones but a lasting effect
what are the three examples of amino acid or amino acid derivative hormones
epinephrine and norepinephrine
thyroxin
triiodothyronine
what amino acid derivatives are fast acting and have transient effects
norepinephrine and epinephrine
what amino acid are the class of amino acid hormones derived from
tyrosine
what are the two ways amino acid derivative hormones interact with a target cell
by binding to receptors on plasma membrane which activates a second messenger
by binding to carrier proteins to pass through the cell membrane then bind to receptor sites on the nucleus
which of the two major hormones classes have storing mechanisms following synthesis
peptides and amino acid derivatives
what is the most typical way a hormone acts upon a target cell
by binding to a specific hormone receptor
where are target cell hormone receptors found
exposed on the surface of a target cell
intracellular receptors within the cytoplasm or nucleus
what two specific hormone classes require cell surface receptors
peptide hormones
catecholamines
what is the function of second messengers when a hormone binds to a cell surface receptor
they amplify the signal initiated by the hormone binding to the cell surface receptor
how are the second messengers produced when hormones are bound to cell surface receptors
the membrane associated G proteins are activated
what four hormones have specific intracellular receptors
steroid hormones
thyroid hormones
vitamin A
vitamin D
what two specific steroids use nuclear initiating signaling
estrogen and progesterone
what are the four ways hormone abnormalities may present as endocrine disease
hormone overproduction
hormone underproduction
altered target tissue response
tumors of an endocrine gland
when do hormone feedback mechanisms occur
when the response to a stimulus influences the original stimulus
when does a negative feedback hormone mechanism occur
when the hormone response diminishes the original stimulus
when does a positive feedback hormonal mechanism occur
when the hormone response enhances the original stimulus
what is the most common hormone feedback mechanism
negative feedback
what is the broad cellular composition of the anterior pituitary lobe
glandular epithelium
what is the broad cellular composition of the posterior pituitary lobe
neural secretory tissue
what are the three derivatives of Rathke’s pouch associated with the anterior pituitary gland
pars distalis
pars intermdia
pars tuberalis
what is the largest derivative of Rathke’s pouch present within the anterior pituitary fland
pars distalis
what derivative of the anterior pituitary is associated with cystic formation
pars intermedia
what derivative of the anterior pituitary is the most vascular
par tuberalis
what are the two embryonic derivatives of the posterior pituitary gland
pars nervosa and infundibulum
what anterior pituitary hormone promotes mammary gland development; initiates milk formation; stimulates and maintains secretion of casein, etc.
prolactin
what anterior pituitary hormone regulates the final maturation of ovarian follicle, ovulation, etc.
luteinizing hormone
what anterior pituitary hormone maintains structure and stimulates secretion of glucocorticoids
adrenocorticotropic hormone (ACTH)
what anterior pituitary hormone stimulates growth of thyroid epithelial cells
thyroid stimulating hormone (TSH)
what anterior pituitary hormone stimulates liver and other organs to make insulin-like growth factor
growth hormone
what anterior pituitary hormone stimulates spermatogenesis in the testis
follicle stimulating hormone (FSH)
what posterior pituitary hormone decreases urine volume
antidiuretic hormone (ADH)
what posterior pituitary hormone stimulates activity of mammary glands to eject milk
oxytocin
what pituitary artery supplies hypothalamus and infundibular stalk
superior hypophyseal arteries
what pituitary arteries supply the pars nervosa of the posterior lobe
inferior hypophyseal arteries
what is unique about the arterial supply of most of the anterior pituitary gland
it does not have a direct arterial blood supply
what is the main function of the hypothalamohypophyseal portal system
provides mechanism for the hypothalamic neuroendocrine to regulate pituitary function
what is the main function of hypophyseal veins
to quickly transport and exchange hormones between the hypothalamus arcuate nucleus and anterior pituitary gland
how would anterior pituitary gland cells that secrete GH and prolactin stain with H&E
they stain red with acidic dyes
how would anterior pituitary gland cells that secrete TSH, ACTH, FH, and LH stain with H&E
stain blue
which anterior pituitary cells have high carbohydrate content and stain positively for PAS
acidophils
what anterior pituitary cells stain poorly with routine H&E
chromophobes
what are the functional cell types of the par distills of the anterior pituitary gland and associated hormone secretion based on IHC
somatotrope
lactotrope
corticotrope
gonadotrope
thyrotrope
is the posterior pituitary gland an endocrine gland
no, it is considered a storage site for the neurosecretions of the hypothalamus
what is the composition of the pars nervosa of the posterior pituitary
contains unmyelinated axons