Bodily Changes in Pain, Hunger, Fear and Rage

tures, this interval would become relatively less exact, (c) A temperature of 25° C. rather than lower was selected because, as Dale and Laidlaw * have shown, the coagulation time is much slower for a given change in temperature below 25° than for the same change above. And with slow- ing of the process the end point, when the determin- ation depends on supporting a weight, is less likely to be sharp, (d) The researches undertaken with use of this coagulometer were concerned with fac- tors hastening the process. For that reason and for reason (b), a long rather than a short coagula- tion time for normal conditions was desirable.

3. Uniformity in the amount and kind of con- tact with foreign surface. — The capacity of the can- nulas was fairly uniform, as stated above; the amount received in them was fairly constant ; and the wire hanging in the blood presented approxi- mately the same surface in different observations. A further condition for insuring consistent treat- ment of the blood in different cases was that of making the tests for coagulation always at the same intervals. Below the writing point of the lever was set an electromagnetic signal E, which recorded half-minutes. At the moment a record was made by the signal (see first signal mark. Fig. 25) the clip on the artery was opened, the blood taken, and the process thus begun. In about 20 seconds the cannula was suspended in the water

batli and the wire was hanging on the lever. At the next record by the signal and at every subsequent record the vertical rod R^ was pushed with the index finger from post P^ to post P^ and allowed to move back. This motion was uniform and lasted about one second. The check R^ on the long arm of the lever was thus raised, and as the wire sank in the blood the writing poiat rose, recording that coagulation had not taken place (see Fig. 25). 4. Definite end point. — As soon as the blood clot- ted, the weight of 30 milligrams was supported, and the failure of the lever to rise to the former height in the regular time allowed, recorded that the change had occurred.

Very rarely the swing of the lever would be checked for a moment and would then begin to move rapidly, indicating that a strand of fibrin had formed but not sufficiently strong to support the weight, and that when the strand broke, the weight quickly sank in the blood. If this occurred, the next record almost always was the short line, which signified that the weight was well supported. A very slight strand of fibrin was able to pre- vent the weight from dropping, though at different times the amount of support differed, as shown by the varying length of the final lines (compare first and last series, Fig. 25). These variations are probably a rough indication of the degree of coagu- lation. In our experiments, however, the length of

the final line was disregarded, and merely the fact that the lever failed to swing through its usual distance was taken as evidence of a clot, and the consequent short record was taken as the end point. As soon as this end point was registered, the tube, wire and cannula were lifted out of the bath ; the cannula was then separated from the tube and pulled away from the wire. The clot was thus dis- closed, confirming the graphic record. The method, at least when used at half-minute intervals, did not reveal in all instances the same degree of clotting. Usually, when the process was very rapid, the revealed clot was a thick jelly; whereas, when the process was slow, a strand of fibrin or at most a small amount of jelly was found. This difference in the degree of coagulation intro- duced, of course, an element of inexactness. In our experiments, however, this inexactness was unfa- vorable to the result we were seeking for, i. e., the acceleration of the process — because the jelly is a later stagfe than the fibrin strand; and since we nevertheless obtained good evidence of accelera- tion, -^e did not in these experiments attempt to determine more accurately differences in the stage of the clotting process.

5. Cleaning of apparatus. — After the wire waS removed from the tube, the clot attached to; its ring-tip was carefully brushed away under Coo^ running water. Under the running water, also, a. trimmed feather was introduced into the cannula and the tube to push out the plasticine and to wash out the blood. Wire, cannula and tube were then dropped into a beaker receiving running hot water (about 80° C.) and there allowed to remain for about five minutes. On removal from this the parts were shaken free from water, passed through 95 per cent alcohol and again shaken free, passed through ether and let dry.

By having a half-dozen cannulas and wires of standard size, it was possible to save trouble by cleaning a number at one time. Not infrequently the first few samples of blood taken from an animal showed rapid or somewhat irregular rates of clotting. Some causes for these initial variations will be presented in following pages. The fairly uniform rate of clotting in any individual after the initial stage, varied in twenty- one different animals from an average of 3 to an average of 10.6 minutes, with a combined average of 5.9 minutes. The conditions for these variations among the individuals have not been wholly deter- mined.

Oct. 27. A cat weighing about 3 kilos was given 3 cubic centimeters of adrenin 1 :1,000, i.e., 1 milli- gram per kilo, under the skin. The animal, in this instance, was kept in uniform ether anesthesia. Following is a record showing when blood was taken, and the coagulation time in each instance : In this case the coagulation time remained at its usual level for about 20 minutes after the subcu- taneous injection.* Thereafter for about an hour the coagulation time averaged 45 per cent of its previous duration. And widely separated tests made during the following hour indicated that ap- proximately the initial rate of clotting had been re- gained.

The rather long period (nearly 30 minutes), in the case just cited, between the injection and the * This period is longer than is expected after the subcuta- neous injection of any drug. As will be shown later, strong doses of adrenin, if injected rapidly, may not at first shorten the clotting process. Probably in some instances of subcu- taneous injection of these strong doses, the drug enters the circulation more rapidly than in others and in consequence coagulation is not at first accelerated.

first appearance of rapid clotting was not the rule. As the following figures show, the coagulation time may become shortened quite promptly after sub- cutaneous injection. In this case nine minutes after the injection the change in the rate of clotting had begun, and it con- tinued more rapid for the subsequent half -hour. We did not attempt to find the minimal subcu- taneous dose which would shorten clotting. A dose of 0.01 milligram per kilo, however, has proved effective, as shown by the following figures :

As will be shown later, the dose in this instance was ten times the minimal effective intravenous dose. On the basis of these figures, less than a milligram of adrenin given subeutaneously would be necessary to shorten clotting to a marked degree in a man of average weight (70 kilograms). Not many observations were made by us on the effects of adrenin administered subcutaneonsly. The amount reaching the vascular system and the rate of its entrance into the blood could be so much more accurately controlled by intravenous than by subcutaneous introduction that most of our atten- tion was devoted to the latter method.

In this procedure a glass cannula was fastened in one of the external jugular veins and filled with the same solution as that to be injected. A short rubber tube was attached and tightly clamped close to the glass. Later, for the injection, the syringe needle was inserted through the rubber and into the fluid in the cannula, the clip on the vein was removed, and the injection made. The smallest amount which produced any change in clotting time was 0.1 cubic centimeter of a dilu- tion of 1 :100,000 in a cat weighing two kilos, a dose of 0.0005 milligram per kilo. Four tests previous to the injection averaged 5 minutes, and none was shorter than 4 minutes. Immediately after the in- jection the time was 2 minutes, but at the next test the effect had disappeared. Doubling the dose in the same cat— i. e., giving 0.2 cubic centi-

meter (0.001 milligram per kilo) — shortened tlie coagulation time for about 40 minutes : From 10.47, immediately after the second injec- tion, till 11.20 the average time for clotting was 2.5 minutes, whereas both before and after this period the time was 4 minutes or longer. At 11.00 o'clock and 11.05, when the end point was reached in 1.5 minutes ( a reduction of 63 per cent), a thick jelly was found on examining the cannula. The changes in clotting time in this case are represented graph- ically in Fig. 26.

In another case a dose of 0.0005 milligram per kilo failed to produce any change, but 0.001 milli- gram per kilo (0.28 cubic centimeter of adrenin, 1 :100,000, given a cat weighing 2.8 kilos) brought a sharp decline in the record, as follows : In these instances the animals were decere- brated. For decerebrate cats, the least amount of adrenin, intravenously, needed to produce shorten- ing of coagulation time is approximately 0.001 milligram per kilo.

In the above cases rapid clotting was manifest directly after minute doses. Larger doses, how- Figure 26. — Shortening of coagulation time after injection of adrenin, 0.2 cubic centimeter, 1:100,000, (0.001 milligram per kilo), at 10:46. In this and following Fig- ures a scale for coagulation time is given in minutes at the left. ever, may produce primarily not faster clotting but slower, and that may be followed in turn by a much shorter coagulation time. The figures below pre- sent such an instance :

This unexpected primary increase of coagula- tion time, lasting at least six minutes, is in strik- ing contrast to the later remarkable shortening of the process from 3 to an average of 1.7 minutes for more than 20 minutes (see Fig. 27, A). If a strong solution, i. e., 1 :10,000, is injected rapidly, the process may be prolonged as above, but not followed as above by shortening, thus : There was in this case no decrease in coagulation time at any test for a half -hour after the injection, but instead a lengthening (see Fig. 27, B). How- ell ^ has reported the interesting observation that repeated massive doses of adrenin given to dogs may so greatly retard coagulation that the animals may be said to be hemophilic. These two instances show that on coagulation large doses have the contrary effect to small, just as Hoskins ^^ showed was true for intestinal and Lyman and I ^^ showed was true for arterial smooth muscle.

In a few experiments the brain and the cord to midthorax were destroyed through the orbit. Arti- ficial respiration then maintained the animal in uni- form condition. Under these circumstances, adre- nin intravenously had more lasting effects than when given to the usual decerebrate animals with intact cord. Fig. 28 illustrates such a case. For thirty minutes before injection the clotting time* averaged 5.4 minutes. Then, about ten minutes after one cubic centimeter of adrenin, 1 :50,000, had

FiGUBB 27. — A, Primary lengthening followed by shortening of the coagulation time when adrenin, 0.5 cubic centimeter 1:10,000 (0.05 milligram), was injected slowly at 2 :43. B, Lengthening of the coagulation time without shortening when the same dose was injected rapidly at 10:08. been slowly injected, clotting began to quicken; during the next twenty minutes the average was 3.4 minutes, and during the following forty-five min- utes the average was 1.9 minutes — only 35 per cent as long as it had been before the injection.

In another case in which the brain and upper cord were similarly destroyed, the clotting time, which for a half -hour had averaged 3.9 minutes, was reduced by one cubic centimeter of adrenin. 1 :100,000, to an average for the next hour and forty minutes of 2.3 minutes, with 1.5 and 3 minutes as extremes. During the first forty minutes of this period of one hour and forty minutes of rapid clot- ting all of eight tests except two showed a coagula- tion time of 2 minutes or less. The explanation of this persistent rapid clotting in animals with spinal cord pithed is not yet clear.

As indicated in Figs. 26, 27 and 28, the records of coagulation show oscillations. Some of these ups and downs are, of course, within the limits of Figure 28. — ^Persistent shortening of the coagulation time after injecting (in an animal with brain and upper cord pithed) adrenin, 1 cubic centimeter, 1:50,000 (0.02 milligram), at 11:01-02. The dash lines represent averages. error of the method, but in our experience they have occurred so characteristically after injection of adrenin, and so often have appeared in a rough

rhythm, that they have given the impression of be- ing real accompaniments of faster clotting. It may be that two factors are operating, one tending to hasten, the other to retard the process, and that the equilibrium disturbed by adrenin is recovered only after interaction to and fro between the two factors. The oscillations in coagulation time after the in- jections suggest that clotting might vary with changes in blood pressure, for that also commonly oscillates after a dose of adrenin (see, e. g., Fig. 23). Simultaneous recording of blood pressure and determining of coagulation time have revealed that each may vary without corresponding varia- tion in the other. Withinj)rdinary limits, there- fore, changes of blood pressure do not change the rate of clotting.

The Hastening of Coagulation by Adrenin Not a Direct Effect on the Blood As previously stated, von den Velden has con- tended that shortening of coagulation time by adre- nin is due to exudation of tissue juices resulting from vasoconstriction. The amount of adrenin which produces markedly faster clotting in the cat, is approximately 0.001 milligram per kilo. As Lyman and I ^^ showed, however, this amount when injected slowly, as in the present experi- ments, results in brief vasodilation rather than

vasoconstriction. Von den Velden's explanation can therefore not be applied to these experiments. He has claimed, furthermore, that adrenin added to blood in vitro makes it clot more rapidly, but, as already noted, he gives no account of the condi- tions of his experiments and no figures. It is im- possible, therefore, to criticise them. His claim, however, is contrary to Wiggers's ^^ earlier ob- servations that blood with added adrenin coagulat- ed no more quickly than blood with an equal amount of added physiological salt solution. Also contrary to this claim are the following two experi- ments : (1) Ligatures were tied around the aorta and inferior vena cava immediately above the dia- phragm, and thus the circulation was confined al- most completely to the anterior part of the animal. Indeed, since the posterior part ceases to function in the absence of blood supply, the preparation may be called an "anterior animal." When such a preparation was made and 0.5 cubic centimeter of adrenin, 1:100,000 (half the usual dose, because, roughly, half an animal), was injected slowly into one of the jugulars, coagulation was not shortened. Whereas for a half -hour before the injection the clotting time averaged 4.6 minutes, for an hour thereafter the average was 5.3 minutes — a pro- longation which may have been due, not to any in- fluence of adrenin, but to failure of the blood to circulate through the intestines and liver. ^* In an-

other experiment after the gastro-intestinal canal and liver had been removed from the animal, the average time for coagulation during twenty-five minutes before injecting adrenin (0.23 cubic centi- meter, 1 :100,000, in an animal weighing originally 2.3 kilos) was 5.5 minutes, and during forty min- utes after the injection it was 6.8 minutes, with no case shorter than 6 minutes. In the absence of cir- culation through the abdominal viscera, therefore, adrenin fails to shorten the clotting time. (2) The cannulas were filled with adrenin, 1:1,000, and emptied just before being introduced into the artery. The small amount of adrenin left on the walls was thus automatically mixed with the drawn blood. Alternate observations with these cannulas wet by adrenin and with the usual dry cannulas showed no noteworthy distinction.

The results of these experiments have made it impossible for us to concede either of von den Velden's claims, i. e., that clotting occurs faster be- cause adrenin is added to the blood, or because adrenin by producing vasoconstriction causes tis- sues to exude coagulant juices. became more rapid as the blood sugar mcreased. Conceivably, faster clotting might result from this higher percentage of blood sugar. Against this assumption, however, is the fact that clotting is greatly accelerated by 0.001 milligram adrenin per kilo of body weight, much less than the dose necessary to increase the sugar content of the blood.^^ And furthermore, when dextrose (3 cubic centimeters of a 10 per cent solution) is added to the blood of an anterior animal, making the blood sugar roughly 0.3 per cent, the coagulation time is not markedly reduced. Adrenin appears to act, therefore, in some other way than by increasing blood^sugar^

Since adrenin makes the blood clot much faster than normally in the intact animal, and fails to have this effect when the circulation is confined to the anterior animal, the inference is justified that in the small doses here employed adrenin produces its remarkable effects, not directly on the blood it- self, not through change in the extensive neuro- muscular, bony, or surface tissues of the body, but through some organ in the abdomen. That exclusion of the liver from the bodily econ- omy, by ligature of its vessels or by phosphorus poisoning, will result in great lengthening of the coagulation time has been clearly shown. .The liver, therefoxe,-seems^t^#urnish continuously to l;he blood a factor in the clotting process which is

being continuously destroyed in the body. It is not unlikely tbat adrenin makes the blood clot more rapidly by stimulating the liver to discharge this factor in greater abimdance. But proof for this suggestion has not yet been established. ° Howell : American Journal of Physiology, 1914, xxxiii, p. xiv. In the foregoing chapter evidence was presented that the intravenous injection of minute amounts of adrenin hastens the clotting of blood. The amounts used did not vary much above or below the amounts discharged by the adrenal glands after brief stimulation of the splanchnic nerves, as found by H. Osgood m the Harvard Laboratory, and may therefore be regarded as physiological. Since injected adrenin is capable of shortening the coagulation time, may not the increased secretion of the adrenals likewise have that effect? The an- swer to this question was the object of an investi- gation by W. L. Mendenhall and myself.^

The blood was taken and its coagulation was re- corded graphically in the manner already de- scribed. In some instances the cats were etherized, in others they were anesthetized with urethane, or were decerebrated. The splanchnic nerves always were stimulated after being cut away from connec- tion witli the spinal cord. Sometimes tlie nerves were isolated unilaterally in the abdomen; some- times, in order to avoid manipulation of the abdom- inal viscera, they were isolated in the thorax and stimulated singly or together. A tetanizing cur- rent was used, barely perceptible on the tongue and too weak to cause by spreading any contrac- tion of skeletal muscles.

That splanchnic stimulation accelerates the clot- ting of blood, and that the effects vary in different animals, are facts illustrated in the following cases : Oct. 25. — A cat was etherized and maintained in uniform ether anesthesia. After forty minutes of preliminary observation the left splanchnic nerves were stimulated in the abdomen. Following are the figures which show the effects on the coagula- tion time: In. this instance at least ten minutes elapsed be- tween the end of stimulation and the beginning of faster clotting. The period of faster clotting, how- ever, lasted for about a half-hour, during which the coagulation time averaged 2.1 minutes, only forty- three per cent of the previous average of 4.8 min- utes. It is noteworthy that the curve (see Fig. 29) ,

Figure 29. — Shortening of coagulation time after stimulation of the left splanchnic nerves, 3:39-:40. while lower, shows oscillations not unlike those which follow injection of adrenin (see p. 155). The primary delay of the effect is not always, indeed it is not commonly, present : Nov. 6. — A cat was anesthetized (1.40 p.m.) with urethane, and later (3.05) its brain was pithed. The following observations on the coagu- lation time show the prompt effect of splanchnic stimulation :