General Anatomy, Applied to Physiology and Medicine, Vol. 3 (of 3)

by Xavier Bichat

Sometimes it is the animal sensibility that is put into action by an affection of the mucous surfaces. The stone, that irritates that of the bladder, causes an itching at the end of the glans penis. That of the intestines being irritated by worms, an inconvenient itching is felt at the end of the nose. Whytt has seen a foreign body introduced into the ear, affect painfully the whole corresponding side of the head; an ulcer of the bladder, produce every time the patient passed water, a pain on the superior part of the thigh, &c. &c.

The sensible organic contractility is often sympathetically excited by the affections of the mucous system. I might at first refer to this subject what I have observed respecting the organic muscles, almost all of which move from an excitement of a contiguous mucous surface; but that is a natural phenomenon; there are many others that are preternatural. A stone that irritates the internal surface of the pelvis of the kidney produces vomiting, which is, as we know, produced any time at will by an irritation of the uvula. The instant the semen passes the urethra in coition, the action of the heart is commonly accelerated. Tissot speaks of a stone which, being entangled in the duct of Warton, produced a sympathetic discharge from the bowels. I saw at the Hôtel Dieu two women, who, whenever they menstruated, and the mucous surface of the womb was consequently in activity, could retain the urine but a short time in the bladder, which contracted involuntarily to expel it the moment it entered it. At ordinary times, there was nothing peculiar in the evacuation of this fluid.

As to the sympathies of insensible contractility and of organic sensibility, they take place when a mucous surface being irritated towards the extremity of an excretory duct, the gland of this duct is brought into action, when, for example, the saliva flows in greater abundance by the action of sialagogues upon the extremity of the Stenonian duct. Whenever there is a gastric derangement and the mucous surface of the stomach consequently suffers, the surface of the tongue is sympathetically affected; the glands situated under this surface increase their action and hence that white mucous coat, that is commonly called a foul tongue, which is a real sympathetic catarrh, but which can however exist idiopathically. Here also is to be referred the remarkable influence of the mucous system upon the cutaneous; thus during digestion, in which the mucous juices pour out abundantly from all sides into the stomach and the intestines, and in which the mucous membranes of the gastric viscera are consequently in great action, the fluid of insensible transpiration is lessened remarkably, according to the observation of Sanctorius; it is in very small quantity three hours after the meal, so that the action of the cutaneous organ is evidently less energetic. Thus during sleep, in which all the internal functions become more evident and are exerted to their utmost, and in which the sensibility of the mucous membranes is consequently strongly developed, the skin seems to be struck with a species of atony; it becomes cold more easily, it allows less substances to escape from it, &c. To these sympathies also can be referred many phenomena of hemorrhages. We know with what facility the mucous surface ceasing, from any accidental cause, to throw out blood, as happens so often on that of the womb, another is immediately affected and discharges this fluid; hence hemorrhages from the nose, the stomach, the chest, &c. from the suppression of those of the uterus, &c.

Passive Sympathies.

In many cases, the other systems being irritated, the animal sensibility of this is brought into action. Among the numerous examples of this fact, the following is a remarkable one. In many diseases in which organs foreign to the mucous system are affected, we experience a sensation of burning heat in the mouth, the stomach, the intestines, &c. and yet the mucous surface, the seat of this sensation, does not disengage more caloric than usual; we may be convinced of this by placing the fingers in the mouth. This sensation is of the same nature as that which we refer to the glans penis when there is a stone in the bladder, as that which is experienced at the end of the nose from worms in the intestines, &c. There is no material cause of pain, and yet there is suffering. Thus in intermittent fevers we experience a cutaneous shivering, though the skin may be as warm as usual; I would observe in respect to this, that the mucous membranes are hardly ever the seat of an analogous sensation of sympathetic cold, but it is almost always a sensation of heat that the aberrations of the vital forces produce in them. Whence arises this difference between them and the cutaneous organs? I know not. I attribute also to a sympathy of animal sensibility the great thirst which takes place in all the severe affections of any part. In all great wounds, after severe operations, in experiments on living animals, &c. we observe this thirst which depends upon a sympathetic affection of the whole mucous surface that extends into the mouth, the stomach and the œsophagus.

Animal contractility cannot be put sympathetically into action in the mucous system, since it does not exist in it.

The same is true of the sensible organic contractility. It is possible that sometimes the kind of motion we have noticed, and which resembles this property, may be sympathetically excited; I know no example of it.

The insensible organic contractility is here very frequently in sympathetic activity. It is the skin especially which exercises by means of this property, a great influence upon the mucous system. 1st. In hemorrhages of the mucous surface of the womb, the nostrils, &c. a cold body applied to the skin in the neighbourhood, contracts this surface and stops the blood. 2d. Who does not know that the production of most catarrhs is often the sudden consequence of the action of cold on the cutaneous organ? 3d. In various affections of the mucous membranes, baths which relax and expand the skin, frequently produce happy effects. 4th. When the temperature of the atmosphere benumbs the cutaneous tone, that of the mucous system receives a remarkable increase of energy. Hence why in winter and in cold climates, in which the functions of the skin are very much diminished, all those of this system increase in proportion. Hence the more evident pulmonary exhalation, the more abundant internal secretions, a more active digestion, more quickly performed and consequently an appetite more easily excited. 5th. When on the contrary the heat of the climate and the season relax and expand the cutaneous surface, the mucous surface is in proportion contracted; in summer, at noon, &c. there is a diminution of the secretions, of that of the urine especially, a slowness in the digestive phenomena from a defect in the action of the stomach and intestines, an appetite slow to return, &c. 6th. In various general affections of the skin, certain portions of the mucous membranes are almost always affected. In scarlet fever, the throat most usually suffers sympathetically. This phenomenon is very common in small pox. 7th. In the latter periods of organic affections of the viscera, as in phthisis, diseases of the heart, enlargements of the liver, cancers of the womb, &c. the mucous membranes are affected like the serous surfaces. The kind of atony in which they then are, produces a more copious flow of mucous juices in them which are altered, become more fluid, &c.; hence the diarrhœas that are called colliquative, which are then to the mucous surfaces, what dropsies are to the serous ones; 8th. It is also to this atony that must be attributed the pectoral hemorrhages which so frequently take place in the last periods of organic diseases, in those of the heart especially. During the short time that I have been at the Hôtel Dieu, there has already died more than twenty patients whom I have opened, of these affections almost forgotten by all practitioners before the time of Corvisart; I have only observed four examples in which passive hemorrhage of the lungs was not the precursor of death.

Character of the Vital Properties.

From what we have thus far said, it is evident that the mucous system is one of those of the whole economy, in which life is the most active. Always in contact with substances that stimulate and irritate it, it is as it were like the skin, in continual action. Yet the life is not the same in all its parts; it undergoes in each remarkable modifications, which no doubt depend on those we have pointed out in the organization of this system, in the nature of its corion, in the arrangement of its papillæ, in the distribution of its vessels and its nerves, in that of its glands, &c.; for as we have seen, none of these essential bases of the mucous system is everywhere arranged in the same manner. There is an organization common to the system, and one peculiar to each of its divisions. It is the same in regard to its life; there is a life common to the system, and as many peculiar ones as there are parts to which it is extended. We know how much the animal sensibility of the pituitary membrane differs from that of the palatine, how powerfully the membrane of the glans penis and the urethra is stimulated by the passage of the semen which makes no impression upon any other mucous surface. The same is true in regard to the organic sensibility and the contractility of the same species. Each mucous surface, in relation with the fluid it is accustomed to, would bear the others with difficulty. The urine would be a stimulant for the stomach and the gastric juice for the bladder; the bile that remains in the gall-bladder would produce a catarrh upon the membrane of the nose, in the vesiculæ seminales, &c.