Volume 1

A text-book of human physiology : including histology and microscopical anatomy : with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition, with additions, by William Stirling.

Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: A text-book of human physiology : including histology and microscopical anatomy : with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition, with additions, by William Stirling. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    596/602 (page 556)
    Head.—The secretory fibres for this part (horse, man, snout of pig) lie in the thoracic sympathetic, pass into the ganglion stellatum, and ascend in the cervical sympathetic (§ 356, A.). Percutaneous electrical stimulation of the cervical syni- patlietic in man causes sweating of that side of the face and of the arm (M. Meyer). In the cephalic j^ortion of the sympatlietic, some of the fibres pass into, or become applied to, the branches of the trigeminus, which explains why stimulation of the infraorbital nerve causes secretion of sweat. Some fibres, however, arise directhj from the roots of the trigeminus {Luclisinger), and the facial (Vuhdan Adamkiewicz). ’ Undoubtedly the cerebium has a direct efiect either upon the vaso-niotor nerves (p. 554, I.) or upon the sweat-secretory fibres (II.), as in the sweating produced by psychical excitement (pain, fear, &c.). Adcimkiev icz and SGiiator found that, in a mazi suffering fronr abscess of the motor re^^ion of the cortex cerebri for the arm, there were spasms and perspiration in the arm. ° Sweat-centre.—Accordmg to Adamkiewicz, the medulla oblongata contains the dominating sweat-centre (§ 373). When this centre is stimrdated in a cat, all the four feet sweat, even three-quarters of an hour after death {Adamkiewicz). III. The ]ierve-fibres Avhich terminate in the smooth muscidar fibres of the siceat- glands act upon the excretion of the secretion. _ Other conditions.—If the sweat-nerves be divided (cat), injection of pilocarpiii causes a secre- tion of sweat, even at the end of three days. After a longer period than six days there may be no secretion at all. This observation coincides with the phenomenon of dryness of the skin in paralysed lirnbs. Dieifenbach found that transplanted portions of skin first began to sweat when their sensibility was restored. Experiments on man.—If a motor nerve (tibial, median, facial) of a man be stimulated, sweat appears on the skin over the muscular area supplied by the nerve, and also upon the correspond- ing area of the opposite non-stimnlated side of the body. This result occurs when the circula- tion is arrested as well as when it is active. Sensory and thermal stimulation of the skin always cause a bilateral reflex secretion independently of the circulation. The area of sweating is independent of the part of the skin stimulated. [Changes in the Cells during Secretion.—In the resting glands of the horse, the cylindrical cells are clear with the nucleus near theii’ attached ends, but after free perspiration they become granular, and their nucleus is more central {Eenaut).'] 288. PATHOLOGICAL VARIATIONS.—1. Anidrosis or diminution of the secretion of sweat occurs in diabetes and the cancerous cachexia, and along with other disturbances of nutrition of the skin in some nervous diseases, e.g., in dementia paralytica ; in some limited regions of the skin, it has occurred in certain tropho-neuroses, c.g., in unilateral atrophy of the face and in paralysed parts. In many of these cases it depends upon paralysis of the corresponding nerves or their sinned swcat-centrcs. 2. Hyperidrosis, or increase of the secretion of sweat, occurs in easily excitable persons, in consequence of the irritation of the nerves concerned (§ 287), e.g., the sweating which occurs in debilitated conditions and in the hysterical (sometimes on the head and hands), and the so- called epileptoid sweats {Eulenlmrg). Sometimes the increase is confined to one side of the Jiead (H. unilateralis). This condition is often accompanied with other nervous phenomena, partlj’ with the symptoms of paralysis of the cervical sympathetic (redness of the face, narrow jHipil), partly with symptoms of stimulation of the sympathetic (dilated pupil, exophthalmos). It may occur without these phenomena, and is due perhaps to stimulation of the proper secretoiy fibres alone. [Increased sweating is very marked in certain fevers, both during their course and at the crisis in some ; while the sweat is not only copious but acid in acute rheumatism. The “ night-sweats” of phthisis are very marked and disagreeable.] 3. Paridrosis or qualitative changes in the secretion of sweat, e.g., the rare case of “sweating of hlood ” (haematohidrosis), is sometimes unilateral. According to Hebra, in some cases this condition represents a vicarious form of menstruation. It is, however, usually one of many phenomena of nervous affections. Bloody sweat sometimes occurs in yellow fever. Bile- pigments have been found in the sweat in jaundice ; blue sweat from indigo (Bizio), from pyocyanin (the rare blue colouring-matter of pus), or from phosphate of the oxide of iron {Osc. KoUmann) is extremely rare. Such coloured sweats are called chromidroses. Numerous micro- organisms (which, however, are innocuous) live between the epidermal scales and on the hairs, two varieties of Saccharomycetes ; in cutaneous folds Leptothrix epidermalis, various Schizo- mycetes, and five kinds of Micrococci; and between the toes—Bacterium gravoolens (Bordoni-