Endocrine Glands 353| CHECKPOINT
15a. Explain the nature of autocrine regulation. How
does it differ from regulation by hormones and
neurotransmitters?
15b. List some of the paracrine regulators produced
by blood vessels and describe their actions. Also,
identify specific growth factors and describe their
actions.
16a. Describe the chemical nature of prostaglandins. List
some of the different forms of prostaglandins and
describe their actions.
16b. Explain the significance of the isoenzymatic forms
of cyclooxygenase in the action of nonsteroidal anti-
inflammatory drugs.
Rachel took prednisolone for its anti-inflammatory and
immunosuppressive effects to treat her arthritis, but the
sustained high doses caused her puffiness. It also sup-
pressed her ACTH secretion and, as a result, caused
atrophy of the adrenal cortex. When she abruptly stopped
taking the prednisolone, her own secretion of glucocorti-
coids was low, causing low blood glucose. This is a type of
Addison’s disease, but it wouldn’t explain her other symp-
toms. A pheochromocytoma, secreting high amounts of
epinephrine and norepinephrine, would account for her
fast pulse and high blood pressure, but was a less likely
explanation than hyperthyroidism. Her blood must have
shown a very low TSH level coupled with a high thyroxine
level for the physician to make the diagnosis of Graves’
disease. He could order a test for thyrotropin receptor
antibody to confirm this. Rachel displayed exophthalmos,
a condition that often occurs in Graves’ disease.
See the additional chapter 11 Clinical Investigations on
Addison’s Disease and Hypothyroidism in the Connect site
for this text.