Endocrinology 1- Basics of Endo Flashcards
Homeostasis
State of equilibrium in body with respect to various functions and to the chemical compositions of the fluids and tissues
If something is “Hyper____” what does that mean
Overproduction of a hormone and/or hypersensitivity to hormonal effects
if something is “hypo____” what does that mean
Underproduction of a hormone and/or sensitivity to hormonal effects
Qualitative disorders vs quantitative disorders
Qualitative woul dbe like a virus - you hve it or not
Quantitative is like an endocrine disorder - you can measure levels
Primary symptoms of an endocrine disorer
Weight/appetite changes fatigue hair loss/hirsutism Cognitive (forgetfulness, confusion) dizziness moodiess (depression/anxiety/aggression)
What would a primary endocrine disorder be?
In a classical endocrine gland (not upstream)
Multiple endocrine neoplasia (MEN)
Some drugs cannot be taken up by people who have this defect in the MEN gene (dominant disorder) - Tumors spontaneously arise in endocrine organs, not at the same time
Congenital hypothyroidism
Condition where there was an iodine deficiency during development - result is short stature and impaired bone formation, as well as severe cognitive impairment and delayed motor function
Sheehan’s Syndrome
Postpartum hemorrhage results in loss of pituitary gland cells —Mikayla I know you do my flash cards, remember this next time you’re having baby fever
What is the most common endocrine disorder in the clinic?
Diabetes Mellitus (esp type 2)
Classical vs non classical endocrine glands
Classical are ductless - just released directly into the blood (and possibly even into extracellular space for Paracrine effects)
Nonclassical would be specialized cells within organs that make and produce hormones (including things like renin-producing cells)
Endocrine means
Hormone is released into the blood and acts on downstream targets
Paracrine means
Hormone is released into the interstitial space and acts on nearby targets
Autocrine means
Hormone is released into the interstitial space and acts on the cell that released it
Factors affecting hormone bioavailability (5)
Hormone target (ex. Binding proteins and kinetics of half life); target tissues (ex. Receptors available and chaperones available); hormone synthesis/release (enzymatic activity, processing, packaging); regulatory mechanisms (such as feedback, circadian rhythm, aging, and pulsitility)
What would be ways hormone transport can affect bioavailability of that hormone
Binding proteins (free vs bound) and kinetics of the half life of the protein and metabolism
What would be ways that target tissues can affect the bioavailability of a hormone
Receptors - they can have mutations, be desensitized, down or upregulated
Chaperone/heat shock proteins that are responsible for stabilization
What are ways in which hormone synthesis and release can impact bioavailability of a hormone?
Enzymatic activity, processing, and packaging
What are ways in which regulatory mechanisms can impact bioavailability of a hormone?
Feedback, circadian rhythms, aging, and pulsitility
How are hormones typically traveling in the blood?
Bound to something else (although a small portion will be free) — this is ESPECIALLY true if the hormone is lipophilic, but there are some that are peptides that will also do this like T3/T4 and IGF-I
What is a benefit of hormones binding to a binding protein?
It greatly increases the half life and in some cases prevents overstimulation of pathways
Bioavailable vs active
Hormones must be unbound to be active - however even bound hormones are often “bioavailable” - can be used if necessary
Are there sometimes sex difference in bioavailability of a hormone? Explain.
Yes - example is testosterone which can be bound to albumin or free (bioavailable) or bound to SHBG -= highly specific binding protein that is not bioavailable but more like a storage depot, and must be cleaved to access testosterone.
How are hormones cleared generally speaking?
Intracellular metabolism, liver metabolism, and urinary/fecal excretion
liver metabolism includes phase I and II (hydroxylation/carboxylation, conjugation) that we talked about in the metabolism lectures
