a. Physiological, Actions of the Glucocorticoids. The glucocorticoids
regulate blood/brain glucose levels. They also inhibit the inflammatory process. The
glucocorticoids also decrease the immunological responses of the body by decreasing
antibody formation. About 90 percent of the glucocorticoids produced is hydrocortisone
(cortisol). One of the most significant metabolic actions of glucocorticoids is
gluconeogenesis. Gluconeogenesis involves the formation of glycogen or glucose from
noncarbohydrates such as fat or protein. This, of course, can act to raise the
concentration of glucose in the blood. Glucocorticoids can also raise the concentration
of glucose in the blood by decreasing the use of glucose by skeletal muscle.
Glucocorticoids play an important role in the body's reaction to stress, although the
specific mechanism for this role is not understood. Glucocorticoids also pay an
important role as anti-inflammatory agents. As anti-inflammatory agents, they decrease
the ability of histamine to dilate blood vessels, decrease the permeability of capillaries,
impair the movement of phagocytes, and cause atrophy of lymphoid tissue (which
causes a decrease in circulating antibodies).
b. Hyposecretion of Glucocorticoids. A decrease in circulating
glucocorticoids often results in anemia, since the glucocorticoids have some effect on
the production of red blood cells.
c. Hypersecretlon of Glucocorticoids. An increase in the production of
glucocorticoids can produce a number of serious effects. One such effect is
osteoporosis, a thinning and weakening of bone. A second effect is the moon face and
the buffalo hump, a condition characterized by atypical disposition of fat in the shoulder
areas (buffalo hump) and in the face (moon face). A third effect is increased
susceptibility to infection due to the anti-inflammatory action of the glucocorticoids.
ABNORMALITIES OF ADRENAL FUNCTIONING
In most individuals, the adrenal glands function as they should. That is, they
produce the hormones needed in the body in the required amounts. However, for one
reason or another, some persons find their adrenal glands not functioning as they
should. Two such conditions are presented below:
a. Addison's Disease. Addison's disease results when the adrenal glands
secrete too little of its hormones into the individual's system. Addison's disease is
characterized by fatigue, muscle weakness, weight loss, low blood pressure, and
b. Cushing's Disease. Cushing's disease results when the adrenal glands
secrete too great a quantity of its hormones into the patient's system. Cushing's
disease is characterized by atypical disposition of fat in the face (referred to as moon
face), in the shoulder areas (referred to as buffalo hump), edema, hypertension, acne,
and diabetes mellitus.