Page:Popular Science Monthly Volume 86.djvu/149

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DUCTLESS GLANDS
145

stimulation of the sympathetic, viz., dilatation of the pupil, dry mouth from diminished salivary secretion, rapid heart action, glycosuria and increased secretion and motility of the stomach and intestines. Hence adrenalin, and drugs, like ergotoxin, which resemble it in action, are variously termed sympathicotropic, sympathicotonic or sympathicomimetic. On the other hand, certain drugs, such as pilocarpin, muscarin, physostigmin, cholin and digitalis, which stimulate the autonomic fibers of the vagus, producing effects diametrically opposite (contraction of the pupils, profuse salivation, slow heart action, pollakiuria, etc.) are termed vagotropic, vagotonic or vagomimetic, because their action simulates the vagal autonomic. Thus the Viennese clinicians postulate two opposing diathetic conditions, sympathicotonus and vagotonus, the symptomatology of which can be thrown into relief by certain pharmacodynamic tests, which have been likened by Januschke to "tuning keys by means of which we can operate upon the complicated stringed instruments of the body, and voluntarily make one string tighter to increase its vibration or another looser to dampen its function."[1] To complete the analogy of their tripod of ductless gland correlations, Eppinger and Hess assume that the pancreas, controlled by the vagal autonomics, secretes a hormone "autonomin," which is supposed to antagonize adrenalin, the hormone of the sympathetic system proper. So far, this is a very cogent and fascinating theory, but, as often happens, it does not work out according to specifications in all cases, and is strongly opposed by Gleg. The symptomatology Id vagotonic and sympathicotonic patients, too complex to be considered here, is extremely variable and the reaction to drugs sometimes unreliable. Thus, Eppinger and Hess themselves found that pilocarpin and adrenalin sometimes produce strong reactions in the same patient. The interest of their theory for present purposes lies in its capacity for elucidating the action of the ductless glands and internal secretion, for behind the ductless glands and the hormones themselves there must be some controlling mechanism. It is assumed that when the vegetative and vagal autonomics are over-excited (sympathicotonia, vagotonia), these act upon the viscera and the ductless glands, the hormones or internal secretions of which in turn react with redoubled force via the blood channels upon the autonomic nerve centers, vegetative and vagal, producing a vicious circle, as Hemmeter maintains.[2] Thus the hormones of the viscera and the internal secretions of the ductless glands regulate the tonus of the nervous system, while the autonomic nerve fibers themselves regulate the action of the ductless glands, the viscera, blood vessels and all organs containing involuntary muscle.

  1. Cited by Barker.
  2. J. C. Hemmeter, New York Med. Jour., 1914, XCIX., 108.