Adrenals - Study Guide Info Flashcards
What are the general functions of the adrenal cortex?
- Protect against sodium and potassium loss
- fuel metabolism
- androgens (sex hormones) also play role
What general hormone type is dealt with in the adrenal cortex?
adrenal steroids
LDL’s attach to receptors called ____ ___ on adrenocortical membranes to form vesicles with _________ to then release cholesterol and synthesize with hormones.
- coated pits
- lysosome
CRH released from _______, which simulates ACTH, then stimulates LDL’s causing _______ to enter mitochondria.
- hypothalamus
- cholesterol
Cholesterol is cleaved by _______ _______ to synthesize pregnenolone.
- cholesterol desmolase
What is the rate limiting step for all cortex hormones bound in plasma by cortisol-binding globulin or transcortin?
pregnenolone
Zona Glomerulosa is associated with major hormone type from the adrenal cortex?
Mineralocorticoid (affects sodium/potassium concentrations)
What mineralocorticoid from the Zona Glomerulosa functions to preserve vascular volume?
Aldosterone
Control of the synthesis of Aldosterone is mediated by what organ?
Kidney
In the zona glomerulosa, what is a major hormonal signal for the increased production of Aldosterone?
Angiotensin II
Cells of the zona glomerulosa are very sensitive to changes in concentration of what ion?
Potassium
Due to increase in Angiotensin II, Aldosterone increases reabsorption of sodium into extra cellular fluid…Potassium then moves out of system by ______ _____ & ATPase control
principle cells
What are the 4 factors that play a role in aldosterone secretion by the zone glomerulosa?
- Increased potassium
- Increased angiotensin II
- Increase in sodium concentration in extracellular fluid slightly decreases aldosterone secretion
- ACTH is necessary for aldosterone but little control in the rate of secretion
What is the condition associated with EXCESS aldosterone in the zona glomerulosa?
Hypokalemia (low potassium) = Muscle weakness
What is the condition associated with DECREASED aldosterone in the zona glomerulosa?
Hyperkalemia (high potassium) = Tetany (muscle spasms)
What are the 2 types of diabetes insipidus associated with decreased aldosterone levels?
Central and Nephrogenic diabetes insipidus
What is the middle and widest layer of the adrenal cortex and secretes glucocorticoids?
Zona Fasciculata
Zona fasciculata is associated with major hormone type from the adrenal cortex?
glucocorticoids
What are the 2 specific glucocorticoids secreted in the zona fasciculata
- cortisol - hydrocortisone
2. corticosterone
What are the 2 major functions of glucocorticoids in the zona fasciculata?
- Stimulate gluconeogenesis (formation of carbohydrate from proteins by the liver)
- Inflammation control
Zona fasciculata enhances the utilization of amino acids by the liver to do what 4 things?
- Increase rate of deamination of amino acids (converts amino acids into usable hydrogen and carbon)
- Increase protein synthesis in the liver
- Increase formation of plasma proteins
- Increase conversion of amino acids to glucose
In the zona fasciculata, cortisol ________ liver and plasma proteins and ______ non-hepatic proteins.
- increases
- decreases
In the zona fasciculata, cortisol promotes/increases what 3 things?
- amino acid from muscle tissues
- it promotes mobilization of fatty acids from adipose.
- this increases free fatty acids in the plasma and increases the utilization of fatty acids for energy.
In the zona fasciculata, the absence of ___________ will cause the fat cells to release fatty acids.
α-glycerophosphate
In the zona fasciculata, cortisol has what 3 anti-inflammatory effects on the body?
- Cortisol stabilizes lysosomal membranes
- Decreases permeability of capillaries
- Decreases white blood cells into inflamed area (decreases prostaglandins and leukotrienes decreasing vasodilation)
Increase in stress increases ACTH secretion thereby increasing the stimulation of cortisol…what are the 5 specific types of stress that may increase cortisol release?
- Trauma
- Infection
- Intense heat or cold
- Surgery
- Disease
Zone reticularis is associated with what 2 major hormones from the adrenal cortex?
Androstenedione
Dehydroepiandrosterone (DHEA)
Androstenedione is a precursor to what androgen hormone?
testosterone
In the zona reticularis what regulates adrenal androgens?
ACTH
What are the 2 catecholamines associated with the adrenal medulla?
Epinephrine (adrenalin)
Norepinephrine (non-adrenalin)
Tissue in the adrenal medulla is refered to as modified _________ ______, embryologically derived from nervous tissue.
modified sympathetic ganglion
In the adrenal medulla, _______ ________ nerve fibers travel from the intermediolateral horn cells of the spinal cord, through the _______ _____ and on through the _______ nerves into the medulla.
preganglionic sympathetic
sympathetic chain
splanchnic
The adrenal medulla receives input from the sympathetic nervous system at what spinal segmental levels? And from what 2 types of adrenergic receptors?
- preganglionic fibers T5 through T11
- Alpha 1 and 2, Beta 1, 2, and 3
Norepinephrine mainly excites what receptor (alpha or beta)?
mainly excites the alpha-receptors and somewhat to a lesser extent the beta-receptors
Epinephrine mainly excites what receptor (alpha or beta)?
Epinephrine excites alpha and beta-receptors EQUALLY
The following effects are associated with what hormones of the adrenal medulla?
- Constriction of most blood vessels of the body
- Increases total peripheral resistance and elevates arterial pressure
- Increased activity of the heart
- Inhibits the gastrointestinal tract
- Dilates pupils of the eyes
Circulating norepinephrine
The following effects are associated with what hormones of the adrenal medulla?
- Effects the cardiac stimulation more
- Weak stimulation of the blood vessels in the muscles compared to norepinephrine
- Increases cardiac output more than norepinephrine
- Has 5-10x as great a metabolic effect as norepinephrine
- Increases the metabolic rate of the body 100% above normal
Circulating epinephrine
What is the adrenal gland disorder associated with HYPOsecretion?
Addisson’s disease
Addison’s disease is caused by hyposecretion of what 2 hormones?
Cortisol and Aldosterone (Adrenal insufficiency)
What is the adrenal gland disorder associated with HYPERsecretion?
Cushing’s disease
Cushing disease is caused by hypersecretion of what hormone?
Cortisol
The following symptoms are associated with what condition?
- Thinning of skin
- Weight gain
- Bruising
- High blood pressure
- Osteoporosis
- Diabetes
- Puffy face – moon face
- Weakness
Cushing’s disease
The following symptoms are associated with what condition?
- Muscle weakness and fatigue
- Weight loss and decreased appetite
- Hyperpigmentation
- Low blood pressure
- Severe fatigue
- Weight loss
- Salt craving
Addisson’s disease
What condition is caused by excessive amounts of androgens in the body?
Adreno-genital Syndrome
The following symptoms are associated with what condition?
- Masculization of the genitalia
- Female fetus – male like genitalia
- Developed female— > Male hair growth, Clitoris enlarged
- Males prepubescent – enlarged penis
Adreno-genital Syndrome
