chromaffin tissue

n.
  1. A cellular tissue, vascular and well supplied with nerves, made up chiefly of chromaffin cells and found in the medulla of the adrenal glands and in the paraganglia.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.