Toxamins in food / by Sir Edward Mellanby.

  • Mellanby, Edward, Sir, 1884-1955
Date:
[1937?]
Catalogue details

Licence: In copyright

Credit: Toxamins in food / by Sir Edward Mellanby. Source: Wellcome Collection.

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    which is responsible for the potential changes and the passage of the impulse may be substances as familiar and as 'non¬ specific’ as potassium or lactate. Whatever view we take of the mechanism of cerebral activity, it is thus almost certain that the final solution can be expressed in terms of chemical change. The most obvious step towards investigating its nature will be to determine the increase in gaseous metabolism, if any, which occurs as the result of activity. So far as we may place reliance on the results of the study of brain tissue in vitro, they indicate that the oxidative mechanisms—dehydrogenases, as well as the pigment cyto¬ chrome and the cytochrome oxidase—are far more abundant in grey matter than in white. In the term ‘ grey matter’, we include nerve cells, non-medullated fibres, and synapses. Since the nerve cells of the posterior root ganglia (in which no synapses are present) are but little better equipped than white matter with this oxidizing machinery, it is just possible that the synapse is the point at which most of the metabolic events take place. And it is to the synapse that physiological theory attributes those characteristics which distinguish conduction in the central nervous system as opposed to conduction in peripheral nerve. REFERENCES (1) Himwich & Nahum. Amer. J. Physiol. 1932,101, 446. (2) Hoffman, Holzlohner & Leegard. Z. Biol. 1932, 93, 108. (3) Holmes & Holmes. Biochem. J. 1925,19, 863. (4) Holmes. Biochem. J. 1930,24,914. (5) Holmes & Sherif. Biochem. J. 1932,26, 381. (6) Holmes. Biochem. J. 1932,26, 2005. ; (7) -J. Physiol. 1935, 85, 400. (8) Kroll. Z. f. ges. Neurol. & Psychiatr. 1933, 143, 780; 146, 208; 147, 316. (9) Wolff. Physiol. Rev. 1936, 16, 545.