McCumbee - Assessment Of Endocrine Function Flashcards
Typically, hormones are degraded at a ______ rate by processes that aren’t regulated
Constant
The quantitative elimination of a hormone from the blood, usually expressed in mL/min
Metabolic clearance rate (MCR)
MRC is _________ to T1/2
Inversely related
How can the rate of hormone secretion be affected? (X3)
By modulating;
Rate of synthesis
Release of hormones stored in secretory granules
Size and number of secretory cells
Endocrine glands secrete hormones in response to ? (X4)
Other hormones
Neurotransmitters
Metabolites
Local mediators (paracrine signaling)
Changes in the amount of hormones circulating is due to ?
Changes in secretion
An assay in which hormone receptors are used in place of an antibody in the assay
Can be used to determine what fraction of the circulating hormone pool is able to bind the hormone receptor (is active)
Receptor-binding assays
Stimulation tests for assessing hormone levels in blood are most likely to be used when an endocrine gland is thought to be _____function
Hypo
Stimulation tests are used to assess the _______ of a gland to produce a hormone
Reserve capacity
Suppression tests for assessing hormone levels in the blood, are most commonly used when an endocrine gland is though to be ______functional
Hyperfunctional
Suppression tests are used to assess ________
The functional status of the negative feedback loop
What does failure to suppress a hormone in a suppression test suggest?
Autonomous secretion of that hormone
Tropic hormone that regulates the target gland
The lower the Kd, the _______ the affinity for binding?
Higher
Kd is equivalent to…
The concentration of hormone required for 1/2 of receptors to be occupied
Conditions that alter receptor affinity (how well the receptor will bind its hormone)
Covalent modification (phosphorylation lowers some receptors)
Inherited receptor mutations
Ionic composition of environment or pH
Allosteric interactions (when one hormone binds, others are less likely to bind)
