Volume 1

Green's Encyclopedia and dictionary of medicine and surgery / edited by J. W. Ballantyne.

Date:
1906-1909
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Green's Encyclopedia and dictionary of medicine and surgery / edited by J. W. Ballantyne. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    81/576 (page 63)
    the HU])r;iren;il bodies came to be regarded as being practically functionless. Witliiii recent years a vast quantity of experi- mental work has been performed on the adrenal bodies. Amongst the numerous observers, Tizzoni, Foa, and Pellaeani, Marino - Zucco, Langlois and Abelous, and especially Oliver and Schafer, are the most prominent. The conclusion to be gathered from a siirvey of this recent work is that the adrenal bodies are necessary to life, and that their complete removal is followed by death, preceded by muscular prostration and other symptoms in some degree analogous to those seen in Addison's disease. In a few instances pigmentation has been produced by experimental removal of the adrenal glands, but it is quite exceptional. The function of the adrenal glands is manifestly not vicariously performed by any other organ when the glands are extirpated, otherwise death would not result. Two views have been put forward as to the nature of this important function :— (i.) That the adrenal glands are katabolic or excretory, that they get rid of, neutralise, or destroy effete blood pigment and toxins, and so prevent their accumidation in the body. (ii.) That the organs are anabolic, and provide an internal secretion analogous to that of the thyroid body, which passes into the circulation and maintains the equilibrium that exists in health. The Theory that the Adrenal Glands are Excretory, or that they neutralise poisons circulating in the blood, rests mainly on the observations of Abelous and Langlois that the blood of animals dying from the effects of re- moval of the adrenal bodies is toxic, and that its effects on other animals more recently de- capsulated is like tiuit of cui'ari. On the other hand, it is pi'obable, as urged by Schafer, that the blood of an animal dying slowly of any disease is toxic, and that its injection into an animal whose resistance has been diminished by a recent operation, would be followed by definite sj'mptoms. The effects of injection of adrenal extract are extremely unlike those of curari, so that at any rate the adrenal bodies do not contain the poisonous bodies that they are supposed to neutralise or excrete. Again, the fact that the blood becomes toxic after removal of an organ can be explained as the result of ab- normal metabolic changes that are then allowed to occur in other parts of the body, the restrain- ing influence which is normally present being the internal secretion of the adrenal bodies. There is no satisfactory proof that the adrenal bodies are excretory. The Theory that' the Adrenal (Elands pro- \mde an Internal Secretion which is necessary to health has been placed on a very firm basis by the experiments of Schafer and Oliver. These observers found that the medulla of the adrenal glands yields an extract possessed of powerful pliysiological properties. Its effects are mani- fested on the heart, blood-vessels, and skeletal muscles. Wiien injected into the circulation there is a marked rise of blood-pressure due to constriction of the arterioles. Oliver has shown by his arteriometer that the calibre of arteries in man diminishes under the influence of the extract. The constriction is not explained by stimulation of the vaso - motor centre, for it occurs after destruction of the central nervous system in frogs, or in a limb after section of its nerves; it is due to a direct action on the muscular tissue of the small arteries. The effect passes off in a few minutes ; when the extract is applied to the inflamed conjimctiva in man vaso-constriction is said to last fifteen minutes. The rapid disappeai'ance is not due to excretion by the kidneys, for it is not aft'ected in animals by clamping the renal arteries ; prob- ably the active princijale becomes stowed away in tiie tissues, and especially the muscles of the body, as shown by the fact that the skeletal muscles show its effects for a longer time than the vascular system. As a result of the high-blood pressure, the beat of the heart is enfeebled and slowed through the influence of the cardio-inhil)itory centre in the medulla. If, however, the vagi are cut or their cardiac terminations paralysed by atropin, the heart beats both more frequentlyand more power- fully than normally. The blood-pressure may then rise to four or five times its normal height. The skeletal muscles are also markedly in- fluenced b}' the extract; a single stimulation of their motor nerve gives rise to very pi'olonged contraction comparable to that produced by veratria. The muscle responds also to direct stimulation. These effects, as already pointed out, in no way correspond to those of curari. When the extract is injected into an animal the knee-jerk disappears, and paralysis, which always appears first in the hind limbs, may follow a sufficient dose. The amount of the extract necessary to produce these effects is remarkably minute ; about half a milligramme for each kilogramme of body weight produces a maximal effect. (Schafer.) A partial immunity has been observed by Swale Vincent after giving the extract. The active principle of the extract is not obtainable from the cortex of the gland, but only from the medulla. It has been found that extracts from the glands in an advanced case of Addison's disease do not exert the specific physiological action, and, as is well known, the patients in this disease exhibit a great muscular debility and a low blood-pressure. The nature of the active principle has not been definitely determined yet. It is not neurine, as was formerly suggested, or pyro- catechin. Moore suggests it is a deriva- tive of pyridene, and quite recently Abel has