On neurotic albuminuria and hæmaturia : more especially in relation to thermic neuroses and to taking cold / by Thomas Laycock, M.D.

  • Laycock, Thomas, 1812-1876.
Date:
1874
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Licence: Public Domain Mark

Credit: On neurotic albuminuria and hæmaturia : more especially in relation to thermic neuroses and to taking cold / by Thomas Laycock, M.D. 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.

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    laws of reflex action to heat-production. Wc can start from the fundamental fact that the body has to be maintained at a certain range of temperature by the conservative and regulative action of the nervous system ; this range is the specific heat witliout which no natural activity can properly go on. Now, it is certain that this is maintained, not only in the body generally, but in par- ticular portions and under varying thermal conditions of surround- ing media, Avhether these tend to raise or to lower the temperature. If we inquire into the action of the regulative mechanism, we find that it varies according as the one or other contingency has to be met. If the surrounding medium abstract heat, then the incident excitor thermic nerves excite the regulating thermic centres, so that a conser- vative reflex influence is exercised on the cooled part, heat is produced therein, and the specific heat maintained. On the other hand, if the surrounding medium add to the heat of the body, a conserva- tive reflex influence is equally exercised, so that due cooling results. The chief means to the latter end seems to be an increased efllux of blood to the sudoriparous glands, so that the surface of the body is covered with water, and cooling results from evaporation. This does not, however, exclude a mechanism for cutting off the supply of oxygen and carbon from the blood-corpuscles to the tissues l)roper by contraction of the blood-vessels. When the production of heat is needed, the conservative process may be held to be exactly analogous to reflex motor acts; we need only to substitute motor energy as heat for motor energy as muscular contraction. There is no question here as to the contraction of the vessels, which is also a physical process, for we know that the abstraction of heat locally causes i^ascular contraction and pallor, while the addition of heat induces dilatation, redness, and increased vascular activity. Such result would also follow on the neurotic and conservative pro- duction of heat in tissues; so that it may well be doubted Avhetlier the results of experimental injury to the ganglia of the sympathetic system, or of lesion of the spinal cord are shown—first, in the dilata- tion of the vessels, and then in the j)roduction of heat. On the contrary, it is heat-production first, and then dilatation and vascular activity. Probably the same order of events occurs in muscular activity. The heat produced excites the activity of the circulation in the muscular tissue, but that is a result of the action of the vis 7iervosa on the muscular mechanism. Carrying this analogy further it can also explain, in some degree, why in certain morbid states of the thermic nerve-centres there is