ACTH is a segment of a much larger glycoprotein prohormone molecule called proopiomelanocortin (POMC). POMC is synthesized by the corticotrophs of the anterior pituitary, which constitute about 10 percent of the gland.
Caviar harvested from an older fish is the more rare, and more sought after, white caviar. The Beluga sturgeon are primarily found in the Caspian Sea, which is surrounded by Iran, Azerbaijan, Russia, Kazakhstan and Turkmenistan. The other primary source of Beluga sturgeon is the Black Sea near Russia and Romania.
For a long time, Caspian Sea caviar from the Beluga, Osetra or Sevruga sturgeon was the only accepted type of caviar in the market. Today, the definition has expanded both semantically and geographically. Caviar is now farmed and harvested not only in Russia and Iran, but also in many different â and surprising - parts in the world, like Bulgaria, France, California, and even Uruguay.