Notes of three lectures on the physiological action of strychnia / delivered by George Harley.

  • Harley, George, 1829-1896.
Date:
[1856]
Catalogue details

Licence: Public Domain Mark

Credit: Notes of three lectures on the physiological action of strychnia / delivered by George Harley. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    affected with severe tetanic spasm, the involuntary muscles of the heart continue to act rhythmically. This small quantity of solution of strychnine, however, which I drop upon the organ, will soon produce tetanic spasm of its muscles. (I saw Pro- fessor Arnold perform this experiment. I am not aware of its being published.) The circulation, in the web of a frog’s foot, seen through the microscope during the tetanic spasm, is observed to be momentarily arrested during the spasm, and then to bound onwards with a sudden jerk. Here is a frog which was poisoned with strychnine two days ago. While the tetanic paroxysm was very severe, of a grain of Wourali poison was introduced into the cellular tissue. In ten minutes, the limbs had become perfectly flaccid, and no irritation induced a spasm. Two hours afterwards, conceiving the animal to be perfectly dead, I opened it, and was astonished to find the heart beating rhythmically. The next day, the heart was found still beating, and the circulation in the web of the foot slow, yet regular. Galvanism applied to the limb accelerated the circulation. Up to the present moment (fifty hours) the animal has pot presented the slightest sign of life; and yet you see circulation continues.* I have already mentioned, that I consider the physiological test the most reliable one for strychnine; and the method of applying it appears to be by injection into the thoracic or ab- dominal cavity. When the poison reaches the lungs, it seems to act most speedily. This is easily explained by the rapidity with which the poison will be absorbed into the blood through the pulmonary capillaries. Into this small frog I inject i0Y8 of a grain of acetate of strychnine; into this other, You may judge by the rapidity with which the symptoms of poison - * Wourali and strychnine have, I find, the effect of reciprocally neutraliz- ing each other, according as the one or the other poison is in excess. Being occupied with experiments on the subject, I shall only cite three:— 1st. A frog was poisoned with Tof a grain of Wourali. Three minutes after it had become perfectly insensible, x$o of a grain of strychnia was in- jected. In five minutes it became tetanic. 2nd. A frog was poisoned with of a grain of strychnia. Three minutes after tetanus was strongly marked, it was punctured with of a grain of Wourali. In seven minutes tetanus disappeared. 3rd. 5 l-g of a grain of Wourali, and of a grain of strychnia, were injected into the abdomen of a frog at five minutes past one; at ten minutes past, it became very tetanic; at half-past one (twenty minutes afterwards) it became perfectly flaccid; and the next day it appeared perfectly well. This is the more astonishing, as the dose of strychnia in this case was certainly more than sufficient to kill it. Thus, it would appear, that strychnine might be used as an antidote for Wourali, and Wourali for strychnine.