Corticosteroids Flashcards
What is a corticosteroid and what does it do?
Steroid that increases gluconeogenesis and increases fat redistribution
What is a mineralocorticoid and what does it do?
Steroid that helps the kidneys and colon with electrolyte and water balance
What is an example of naturally produced mineralocorticoid:
Aldosterone and Deoxycortisone
Do high anti-inflammatory, immunosuppressant activity and effects on carb and protein metabolism correlate more with glucocorticoid or mineralocorticoid activity?
Glucocorticoid activity
What is the predominant action of glucocorticoids on intermediary metabolism?
Increase the breakdown of proteins and lipids (gluconeogenesis)
T/F Corticosteroids also cause an increase in glycogenolysis
FALSE; they do not change glycogenolysis
What is the predominant action of corticosteroids on CNS?
Glucocorticoids: excitation and euphoria
Mineralocorticoids: decrease excitability by decreasing K in the ECF/ICF –> Hyperpolarization –> decreased excitability
What effects does glucocorticoids have on the lymphoid tissues and immune responses?
Increase PMNs, monocytes, and platelets, while decreasing lymphocytes, eosinophils, and basophils
Decreases the production of IL 1 and 2
Increases immunosuppresive cytokine production
What can the use of glucocorticoids lead to in regards to immune and lymphoid tissues/
Increases circulating RBC, neutrophils, and platelets
Decreases circulating lymphocytes, and basophils
Can also decrease size of LNs and thymus
Why would you use glucocorticoids in a lymphoid tissue setting?
Can supplement the treatment of lymphoma or mast cell tumors
Can be used to control excessive humoral or cellular reactions
Glucocorticoids can have what effect on RBCs?
Increases RBCs leading to polycythemia
Glucocorticoids have what effect on inflammatory processes?
Anti-inflammatory due to suppression of immune system
DOES NOT suppress the underlying issue
What effects do glucocorticoids have on skeletal muscle function? Mineralocorticoids?
Deficiency can cause weakness due to hypoglycemia and poor circulation
Excess M: hypokalemia which causes weakness in muscles
What effects do glucocorticoids have on electrolyte and water balance? Mineralocorticoids?
G: Incerase the cardiac output leads to increase GFR; after while can lead to PU/PD
M: Increase Na and HCO3 retention and increase H, Cl, and K excretion
What effects does glucocorticoids have on the respiratory tract?
Increases the expression of Beta-2: bronchodilation
Increase expresion of alpha-2: vasoconstriction
Helps with anti-inflammatory
What effects does M&G have on cardiovascular system?
Increases the vasomotor responses and myocardial contraction.
M: Increases Na in ECF = increased BP
M: Decreases K in ECF = increases myocardial Ca
G: increase the expression of A-adrenergic receptors in BVs and Beta-adrenergic receptors in heart
What are the clinical signs of hyperadrenocorticism? How do these relate to the actions of the steroids?
PU/PD: diurect effect from excretion of glucose and ions
Polyphagia: trying to eat more glucose so they don’t have to bkdown their body
Potbelly: weakness of abdominal muscles
Muscle weakness: breakdown of muscle
Recurrent UTI: Lots of glucose and ions in the urine for bacT and the immune system is suppressed
Dermatologic conditions: not enough energy to grow hair
What are the clinical signs of hypoadrenocorticism? How do these relate to the actions of the steroids?
Dehydrated: body isn’t retaining Na or glucose so water flows out of the body
Hypotension: dehydrated
Bradycardia: dehydrated
Renal failure: no aldosterone produced; losing Na and water –> medullary washout
Circulation collapse: dehydration
How does an animal get hyperadrenocorticism from steroid treatment?
Vet continually keeps the animal on steroid treatment
How does an animal get hypoadrenocorticism from steroid use?
Had them on corticosteroids, adrenal crotex atrophies, and then takes them off the corticosteroids