The vaso-motor system / by Sir William M. Bayliss.

  • Bayliss, William Maddock, Sir, 1860-1924.
Date:
1923
Catalogue details

Licence: In copyright

Credit: The vaso-motor system / by Sir William M. Bayliss. Source: Wellcome Collection.

    123/180 (page 111)
    CHEMICAL AND PHARMACOLOGICAL ACTION ON ARTERIOLES. We pass on to the discussion of the arterial constriction and relaxation brought about by the direct action on them of chemical substances. The effects to be considered are those upon the muscular tissue itself or on the myo-neural junctions and is one part of the general action of such substances on smooth muscle. The case of the capillaries is of a different nature and will be discussed in the next chapter. The importance of the effect of the products of tissue activity on the blood vessels of these tissues was pointed out by Gaskell (1880, p. 68). His work on the vaso-motor mechanism of the voluntary muscles (1876) had convinced him that acid substances produced in their contraction had a direct action on the blood vessels, causing the muscle of the arterioles to relax. Accordingly, he investigated (1880) the action of acids and alkalies on the heart and blood vessels of the frog, showing that lactic acid caused dilatation and sodium hydroxide contraction. At a later date (1901), I showed that carbon dioxide acts in the same way as lactic acid (see Figure 8 above). Carbon dioxide is a pro¬ duct of oxidation in all kinds of cells, whereas, so far as evidence goes, lactic acid is a normal product only in the case of muscle. Or perhaps it would be more correct to