Concluding Articles of Symposium on Regulation of the Cardiovascular System in Health and Disease To Appear Issue Regulation of Blood Volume
- Concluding Articles of Symposium on Regulation of…
ONE of the known causes of hypertensioll is a pheochromocytoma, a tumor of the medullary portion of the adrenal gland that secretes epinephrine or norepinephrine in varied but increased amounts. It produces either sustained hypertension or paroxysmal hypertension frequently associated with bizarre symptoms during the attack, together with hypermetabolism and high blood sugar in some instances. Although pheochromocytoma is rare, it is being diagnosed oftener and will beconle inereasingly important with safe surgical renmoval. Thus the correct preoperative diagnosis becomes imperative and can sometimes be lifesaving. An estimated 90 per cent of pheochromocytomas arise from the adrenal medulla, but they may occur wherever chromaffin tissue is found along the sympathetic nervous systein. Of pheochromocytomas found outside the adrenal glands, 6 have been found in the thorax, 4 in the urinary bladder, and 18 in the organ of Zuekerkandl. Multiple tumors may occur in both adrenal glands or along the aorta in the sympathetic chain; some of the latter tumors may be metastatic, as approximately 10 per cent of pheochromocytomas are malignant. Familial pheochromocytoma has been reported.