Further observations on the action of [beta]-iminazolylethylamine / by H.H. Dale and P.P. Laidlaw.

  • Dale, Henry Hallett, 1875-1968.
Date:
1911
Catalogue details

Licence: In copyright

Credit: Further observations on the action of [beta]-iminazolylethylamine / by H.H. Dale and P.P. Laidlaw. 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.

    9/22 (page 185)
    (a) The possible liberation of a vaso-dilator substance. There is no evidence in favour of this, but it has been adopted by Popielski1 in a criticism of our former paper, and must, therefore, be considered. According to Popielski, /3-I. is one of a series of substances (including atropine and morphine) which cause the liberation of the hypothetical “ vasodilatin ” when injected intravenously. The arguments adduced by Popielski are based on our observations: (1) that /S-I. does not produce all the effects of “vasodilatin,” neither depriving the blood of the injected animal of coagulability, nor producing tolerance to further injections of itself; (2) that /3-I. causes vaso-constriction when perfused through organs of the dog or cat or injected intravenously into the rabbit. Fig. 3. Perfused hind-limbs of cat. At J injected 0-1 mgm. j8-I. into arterial cannula. Lever adjusted at x — x. It appears to us that (1) is a sound argument against the suggested mode of action : a substance acting by liberation of “ vasodilatin would presumably produce all its effects, each in its normal relative prominence; and there is no obvious reason why an animal should not become tolerant of “ vasodilatin ” with equal readiness whether it is secondarily liberated or primarily injected. The observations under (2) constitute the anomaly which we are discussing, and which would, indeed, receive a possible explanation 1 Zntrlb. f. Phy»iol. xxiv. p. 1102. 1910.