On the electrical phenomena accompanying secretion in the skin of the frog / by W.M. Bayliss and J. Rose Bradford.

  • Bayliss, William Maddock, Sir, 1860-1924.
Date:
[1885?]
Catalogue details

Licence: Public Domain Mark

Credit: On the electrical phenomena accompanying secretion in the skin of the frog / by W.M. Bayliss and J. Rose Bradford. 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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    preparation, when dropping atropin solution on the skin put an end to the excitatory change. In any case, however, large doses are required to abolish the negative phase; the positive is comparatively easily annihilated, 5 mgms. sometimes doing so, while the negative phase remains large. These facts may be explained on Hermann’s second hypothesis by bearing in mind, as does Hermann himself, the known paralysing effect of atropin on smooth muscular fibre when given in large doses. The positive phase, according to the hypothesis in question, being dependent on the activity of the gland cells is easily abolished, while the negative, which requires the agency of the muscular coat, will be only abolished by doses which paralyse the latter. Other Amphibia. It remains to shortly mention the results we have obtained in other Amphibia. We have obtained excitatory variations in the skin of the toad, newt, salamander and tree frog. In the first three the effect is usually considerable, though very slow in its time course and by no means so regular as in the frog; we have seen pure positive and pure negative variations as well as all kinds of combinations of these; on the whole the pure negative preponderates. The largest variation is given by the lateral glands of the salamander, and is usually a pure negative one. The actions of corrosive sublimate and atropin appear to be analogous to their actions on the frog but not so constant or so powerful; and owing to the very slow time course of the variation in these creatures it is considerably more difficult to be certain what the effect is, since the current of rest is almost always rapidly varying, either increasing or decreasing; and when the variation happens to be in the same direction as the change of the current of rest, it is frequently impossible to detect it. We have only made use of one tree frog and therefore cannot generalize in this case, but in this case the excitatory change was the same as in the ordinary frog.