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Above and behind the mouth cavity, tucked into a cradle of bone at the base of the human brain, lies a reddish nugget of tissue, no bigger than a big pea in normal adults-the pituitary gland. Galen, the famed physician of antiquity, and Vesalius, the great anatomist of the Renaissance, knew it. They thought it gave saliva. In 1783 an Irishman named Charles O'Brien died at the age of 22. He was 8 ft. 4 in. tall. A curious physician bought his body for $2,500, dissected the head, found a pituitary gland almost...
...pushed until the 1920s, when Herbert McLean Evans of the University of California caused rats to become giants by injecting them with crude pituitary extract. He dwarfed rats by pituitary removal, then with pituitary injections restored them to normal size. He made it clear that the reddish little gland was intimately concerned with one of the most important of biological processes-growth. Since then the veil of ignorance has been gradually lifted...
Front Lobe. The pituitary gland consists of three parts, two lobes and a narrow middle. In the smaller rear lobe, two hormones have been fairly well identified (alpha-hypophamine and beta-hypophamine), which appear respectively to influence uterine contractions and blood pressure. Biochemist James Bertram Collip of Montreal's McGill University discovered a hormone of the middle pituitary (appropriately called intermedia) which affects, though it does not exclusively control, the blood sugar level...
...hormones secreted by the larger front lobe make the pituitary the "master gland." Yet no one knows just what or how many hormones the front lobe secretes. The trouble is that-although a few front lobe hormones have been freed of all but small traces of impurities-a living body's response under test may be due not to the hormone tested but to an "impurity...
Moreover, some responses are not due to one hormone, but to the combined action of two or more. This phenomenon is called "synergism." The work of Evans and others convinced many a gland man that the pituitary secreted a "growth hormone." Riddle's researches, however, tend to show that growth is a synergic response to two hormones, thyrotropin and prolactin. He also believes that this same pair get together in another synergism to maintain body heat...