Basically, a pheochromocytoma is a tumor of these catecholamine-secreting cells, and that causes the clinical signs and symptoms we will discuss below. The catecholamine-secreting cells are sometimes referred to as chromaffin cells, and they are found in other areas of the body as well as in the adrenal medulla.
Â© The Associated Press Carrie Underwood arrives at the CMT Music Awards at Bridgestone Arena on Wednesday, June 10, 2015, in Nashville, Tenn. (Photo by Sanford Myers/Invision/AP) The show in Nashville, Tennessee, marked Underwood's fourth consecutive victory for video of the year.
Other performers at the CMT Awards included top country singers such as Carrie Underwood, Luke Bryan, Florida Georgia Line and Aldean. Erin Andrews and NFL star J.J. Watt hosted the show. The Associated Press contributed to this report. Follow FOX411 Country's Sasha Bogursky on Twitter @SashaFB.