A-Textbook-of-Clinical-Pharmacology-and-Therapeutics-5th-edition

ADRENAL CORTEX 303
Table 40.1: Actions of cortisol and consequences of under- and over-secretion
Actions Deficiency Excess
Carbohydrate, protein Enhances gluconeogenesis; antagonizes Hypoglycaemia, loss Cushing’s syndrome: weight
and fat metabolism insulin; hyperglycaemia with or without of weight gain, increase in trunk fat,
diabetes mellitus; centripetal fat deposition;
moon face, skin striae,
hypertriglyceridaemia; hypercholesterolaemia;
bruising, atrophy, wasting
decreased protein synthesis (e.g. diminished
of limb muscles
skin collagen)
Water and salt Inhibits fluid shift from extracellular to Loss of weight, Oedema, thirst, polyuria;
metabolism intracellular compartment; antagonizes hypovolaemia, hypertension; muscular
vasopressin action on kidney; increases hyponatraemia weakness
vasopressin destruction and decreases its
production. Sodium and water retention,
potassium loss
Haematological Lowers lymphocyte and eosinophil counts; Florid complexion and
increases neutrophils, platelets and
polycythaemia
clotting tendency
Alimentary Increases production of gastric acid and pepsin Anorexia and nausea Dyspepsia; aggravation of
peptic ulcer
Cardiovascular system Sensitizes arterioles to catecholamines; Hypotension, fainting Hypertension,
enhances production of angiotensinogen.
atherosclerosis
Fall in high-density lipoprotein with increased
total cholesterol
Skeletal Decrease production of cartilage and Backache due to
osteoporosis; antivitamin D; increased renal
osteoporosis, renal calculi,
loss of calcium; renal calculus formation
dwarfing in children (also
anti-GH effect)
Nervous system Altered neuronal excitability; inhibition of Depression and other
uptake of catecholamines
psychiatric changes
Anti-inflammatory Reduces formation of fluid and cellular exudate; Increased spread of and
fibrous tissue repair
proneness to infections
Immunological Large dose lysis lymphocytes and plasma cells Reduced lymphocyte mass,
(transient release of immunoglobulin)
diminished immunoglobulin
production
Feedback Inhibits release of ACTH and MSH Pigmentation of skin and
mucosa
ACTH, adrenocorticotropic hormone; MSH, melanocyte-stimulating hormone; GH, growth hormone.
HYDROCORTISONE (CORTISOL)
Uses
Hydrocortisone has predominantly glucocorticoid effects, but
also has significant mineralocorticoid activity (Table 40.2).
At physiological concentrations, it plays little if any part in
controlling blood glucose, but it does cause hyperglycaemia
(and can precipitate frank diabetes mellitus) when administered
in pharmacological doses. This is caused by enhanced
gluconeogenesis combined with reduced sensitivity to insulin.
Hydrocortisone is given (usually with fludrocortisone to
replace mineralocorticoid) as replacement therapy in patients
with adrenocortical insufficiency.
High-dose intravenous hydrocortisone is used short term
to treat acute severe asthma (usually followed by oral prednisolone)
or autoimmune inflammatory diseases (e.g. acute
inflammatory bowel disease). Hydrocortisone acetate is an
insoluble suspension which can be injected into joints or