Endocrinology General Principles Flashcards
What do vitamin D and thyroid hormone receptor have in common
Both have receptors that resemble steroid receptors
Steroid receptors bind DNA with what type of domain?
Zinc Fingers
Exocrine glands are [ductless/have ducts] while endocrine glands are [ductless/have ducts]
Endo - ductless (directly into blood)
Exo - have ducts
Steroid hormones are derived from _. Thyroxine, Epi and norepi are derived from _
CHolesterol
Tyrosine
While adrenal medullary hormones are stored In vesicle, how are steroid hormons stored?
They aren’t. They are secreted as soon as made
Receptors for glucocorticoids and mineralocorticoids are found in _. The receptors for steroids are found in _
Cytoplasm
Nucleus
Three ways that GPCRs can exert their effects are _
cAMP - CREB (phophorlated, nuclear transcription factor)
Ca++
Membrane lipids
Steroid receptors are [short/long] acting.
Long. Require transcription for their effects
Steroid receptors assoc with HSP90 b/c (2)
Maintain receptor shape
Mask DNA binding domain
What causes HSP dissociation from the receptor?
Ligand binding.
In addition to long term effects, steroid receptors have rapid effects. They are accomplished by _
Modulation of already existing proteins
Responsiveness of a hormone refers to _ while sensitivity of a hormone refers to _
Responsiveness - Max effect
Sensitivity - [hormone] for effect ([H} for 50% effect)
Peptide hormones circulate bound to _ in their [active/inactive] forms, while steroid hormones circulate bout to _ in their [active/inactive] forms
Plasma proteins - active
Specific hepatic globulins - inactive until they dissociate
A specific limitation of RIA mentioned in the notes is _
The RIA might recognize a biologically inactive version of the hormone
What is metabolic clearance rate? How is it related to plasma half life?
The rate at which a molecule is removed from plasma. It is inversely related
