Intro stuff 171 and 172 Flashcards
Differentiate endocrine, exocrine, paracrine, autocrine.
where are they made and where do they go
Endocrine –> made in a gland, acts on distant target via circulation
Exocrine –> made in a gland, released locally on tissue via a duct
Paracrine –> made by cells, released into extracellular space and acts locally on nearby cells
Autocrine –> made by gland, acts on gland itself
Which type of secretion is this:
trypsin, an enzyme released by pancreatic exocrine cells, is released into pancreatic ducts and ends up in the small intestine to help break down ingested proteins
exocrine secretion
acts locally on tissue at the end of the duct
Which type of secretion is this:
TGF-beta acts locally on cell divisionof nearby cells
paracrine
acts on surrounding cells/tissues
Which type of secretion is this:
IL-1 binds on the gland that produces it in order to modulate gland function
autocrine
binds on its own gland
What are the three major classes of hormones?
peptides, steroid derivatives, amino acid derivatives
Peptide hormones are initially synthesized as _________ and are __________ to active form. They bind ______________ receptors.
Peptide hormones are initially synthesized as larger peptides and are cleaved to active form. They bind extracellular membrane-bound receptors.
Steroid hormones are initially derived from __________. They bind __________ with translocation to the __________ for _____________.
Steroid hormones are initially derived from cholesterol. They bind cytoplasmic receptors with translocation to the nucleus for DNA binding.
Amino Acid hormones are derived from __________. They bind to _________ receptors where they ___________ and bind to ___________.
Amino Acid hormones are derived from tyrosine. They bind to extracellular membrane-bound receptors where they cross the cell membrane and bind to nuclear receptors.
What are negative feedback loops? Positive feedback?
negative feedback –> an end product of a reaction acts on an earlier stage of the reaction to downregulate it
positive feedback –> an end product of a reaction acts on an earlier stage of the reaction to upregulate it
What is autonomy in the context of endocrine tumors?
endocrine tumors lose some, but not all, of their feedback control
ex. an endocrine tumor may not respond to signals that should downregulate hormone production, but may still respond to signals that upregulate it (and make the tumor worse)
What hormones are produced by the anterior pituitary (6)?
- growth hormone
- prolactin
- leutinizing hormone
- follicle stimulating hormone
- adrenocorticotropic hormone
- thyroid stimulating hormone
What is the effect of the following hypothalamic hormones on growth hormone release:
GHRH (+ or -)
somatostatin (+ or -)
GHRH (+)
somatostatin (-)
What is the effect of the following hypothalamic hormones on prolactin release:
dopamine (+ or -)
VIP (+ or -)
dopamine (-)
VIP (+)
What is the effect of gonadotropin releasing hormone on:
lutenizing hormone (+ or -)
follicle stimulating hormone (+ or -)
lutenizing hormone (+)
follicle stimulating hormone (+)
Tumors of cells producing which hormones correspond to the following syndromes:
a) acromegaly
b) Cushing’s disease
c) prolactinoma
d) hyperthyroidism
a) acromegaly –> growth hormone
b) Cushing’s disease –> ACTH
c) prolactinoma –> prolactin
d) hyperthyroidism –> thyroid stimulating hormone
What hormones are produced by the posterior pituitary (2)? What do they do?
vasopressin: controls water reabsorption by distal tubule
oxytocin: responsible for milk let-down in the puerperium
What subclasses of hormones are produced in the adrenal cortex (3)? What do they do?
glucocorticoids (ex. cortisol) –> withstand stress, increase glucose
mineralocorticoids (ex. aldosterone) –> Na retention, BP elevation
androgens –> causes virilization in women
What hormone is produced by parathyroid glands (1)? What does it do?
parathyroid hormone (made by Chief cells)
stimulates calcium resorption from bone, calcium reabsorption by kidneys, calcium uptake from intestines
Insulin regulates blood glucose levels by stimulating ________ by tissues and inhibiting hepatic __________.
Insulin regulates blood glucose levels by stimulating glucose uptake by tissues and inhibiting hepatic glucose production.
Glucagon __________ hepatic glucose production.
Glucagon stimulates hepatic glucose production.
Where is epinephrine and norepinephrine produced?
sympathetic nervous system and adrenal medulla
What type of gland is a sweat gland?
exocrine gland
sweat glands pour out their secretions onto the surface of the skin and not into the blood, which would have made them endocrine glands