The inhibition of lactic acid formation in cancer and muscle / by Sylvia Thurlow Harrison and Edward Mellanby.

  • Harrison, Sylvia Thurlow.
Date:
[1930?]
Catalogue details

Licence: In copyright

Credit: The inhibition of lactic acid formation in cancer and muscle / by Sylvia Thurlow Harrison and Edward Mellanby. Source: Wellcome Collection.

    2/20
    creatic extracts also inhibit lactic acid formation in the soluble muscle enzyme system of Meyerhof [1926]. The present paper shows the effect of pancreatic extracts on cancer metabolism. This work was begun in May, 1928, and many of the experiments to be described had been completed when in December, 1928, a paper appeared by Barr, Ronzoni and Glaser [1928] in which the authors described experiments which had been undertaken with the same aim as our own, namely, to see whether pancreatic preparations inhibited the glycolysis of cancer tissue. Taking their results as a whole, they concluded that pancreatic extract did not inhibit this glycolysis. Our own experiments had led us to the opposite conclusion, and since some inhibition had been obtained in a number of Barr, Ronzoni and Glaser’s experiments, we decided to continue our work. Experimental. Warburg has shown that not only is the anaerobic glycolysis of cancer tissue high, but also the aerobic glycolysis, whereas normal adult tissue shows practically no aerobic glycolysis. We therefore studied first the effect of pancreatic extracts on the aerobic glycolysis of cancer tissue. The type of manometric apparatus and technique described by Warburg were used. In all of these experiments, a thin slice of cancer tissue was suspended in bicar¬ bonate Ringer solution (0*25M with respect to bicarbonate). When glycolysis was being measured, the Ringer contained 0-2 % glucose. Each apparatus was filled with a mixture of 95 % air and 5 % C02 and shaken in a water- bath at 37° for 1 hour. At the end of the experiment, the tissue was removed, washed, dried and weighed. A watery extract of commercial pancreatin was made by allowing 0-5 g. of the dry preparation to stand in 5 cc. water for an hour and then filtering. This preparation was made fresh every day. Another extract was made according to the method of Foster and Woodrow [1924] in which the factor is precipitated by 70 % alcohol. In all the later experiments, the pancreatic preparation from fresh pancreas described by Ronzoni, Glaser and Barr [1928] was used. This is precipitated by 58 % alcohol. Preliminary experiments showed that heated pancreatic extract did not inhibit the glycolysis of cancer tissue. In investigating the action of the pancreatic extracts, the same amount of heated extract was always added to the control apparatus as of unheated extract to the experimental apparatus, the two solutions being in this way more comparable than if water were used in the control. The pancreatic extract for the control was immersed in a test-tube in boiling water for 5 minutes. The pH of heated and unheated extracts was brought to 7-6 before using. The malignant tissue used was for the most part mouse carcinoma 63, and occasionally the slow growing Twort carcinoma, both kindly supplied by Dr J. A. Murray, F.R.S., of the Imperial Cancer Research Institute. Rat carcinoma 9 was tried but great difficulty was experienced in getting tumours that were not necrotic or haemorrhagic.