United States or Austria ? Vote for the TOP Country of the Week !
A simplified device has lately rendered it practicable to make actual determinations by a few five-minute readings of the rate of oxygen absorption by the lungs. Plummer, also connected with the Mayo Foundation, has shown that what would amount to less than a grain of the thyroxin would more than double the amount of energy produced in a unit of time.
By the administration of thyroxin, her metabolic rate can be raised to any desired figure, the spark can be adjusted, so to speak, to any point we like, and it can be so maintained for years. In the normal animal, to be sure, the internal secretion of the thyroid is not absolutely essential to life.
The thyroid-centered individual, of the excess thyroid type, actually burns up more food and produces more heat than the ordinary organism. He burns himself up faster in general. When the thyroid sends more secretion into the blood, more thyroxin, it accelerates all the functions and activities of the organs. Tea and coffee produce loquacity because they stimulate the thyroid.
Besides thyroxin, adrenalin, and the libido-producing secretion of the interstitial cells, the substance produced by the paired glandlets, situated behind the thyroid, the parathyroids, have a profound influence upon the vegetative apparatus and the vegetative nervous system. These direct the lime exchanges within the cells of the organisms, including the nerve cells.
To be exact, one milligram of thyroxin increases the metabolic rate two per cent. That illustrates some of the power of the internal secretion of the thyroid and its importance to normal life. But not only is the height of pressure of energy in the cells controlled by the thyroid. The mobility of that energy is also controlled.
Even if self-destruction were avoided by the ingestion of the largest quantities of energy-bearing foods, rest for the cells would be difficult, if not impossible. The thyroxin in the tissues diminishes after a period of great exertion, the thyroxin probably being carried back to the thyroid gland and kept there as reserve until further demand.
A woman suffering with myxedema, the condition described by the English physician Gull as a cretinoid state supervening in the adult life of woman, has an insufficient amount of thyroxin in her blood and tissues. She is clumsy and awkward and will stumble when endeavoring to walk upstairs.
The isolation of thyroxin has made possible the determination of the influence of the thyroid hormone upon the evolution of energy in any higher animal organism. There is, for every individual, a constant, known as the metabolic rate, or the combustion rate, a reading of the rate at which his cells are consuming material for heat.
Then there is a gradual decrease in the intensity of reaction for another ten days. So that the length of time a single administration of thyroxin functions within the body is about three weeks. Again we have occasion to notice a protective device of the cells.
Since the liver is the most complex and active chemical factory in the body, its appropriation of a greater amount of iodine for itself is understandable. When thyroxin is administered in a single dose, there is a distinct lag in the absorption of it by the tissues. A single dose does not generate its maximum effect until the tenth day. This effect continues for about ten days.
Word Of The Day