A note on the inhibitory effect of monoiodoacetic acid on lactic acid production by cancer tissue / by Sylvia Thurlow Harrison and Edward Mellanby.

  • Harrison, Sylvia Thurlow.
Date:
[1931?]
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Licence: In copyright

Credit: A note on the inhibitory effect of monoiodoacetic acid on lactic acid production by cancer tissue / by Sylvia Thurlow Harrison and Edward Mellanby. Source: Wellcome Collection.

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    acid already present1. Tire flasks were then stoppered and shaken for 3 hours at 37° and, after removal of proteins and carbohydrates, the lactic acid was estimated by the method of Friedemann, Cotonio and Shaffer [1927]. Table I. Aerobic glycolysis of tumour tissue as affected by iodoacetic acid. mg. lactic acid per g. dry weight tissue mg. Exp. 1. Control ... ... ... ... 39-1 Iodoacetic acid 2 mg. in 30 cc. 14-5 Exp. 2. Control ... ... .... ... 41-4 Iodoacetic acid 4 mg. in 30 cc. 7-3 Exp. 3. Control ... ... ... ... 34-6 Iodoacetic acid 4 mg. in 30 cc. 1-0 Exp. 4. Control ... ... ... ... 30-3 Iodoacetic acid 1 mg. in 30 cc. 8-9 „ 2 mg. in 30 cc. 5-6 „ 4 mg. in 30 cc. 3-0 In Exp. 3, the tissue had been shaken for an hour in bicarbonate Ringer’s solution and then put into fresh Ringer’s solution with glucose and shaken with and without iodoacetic acid. Experiments in vivo. Several experiments were done in which iodoacetic acid was injected in a sublethal dose into mice bearing tumour 63. After a given time, the animals were killed and the glycolysis of the tumour compared with that of tumours from uninjected animals. In order to make the control as valid as possible, both the injected and uninjected animals bore tumours from the same inocu¬ lation. Since there is some variation in the glycolytic values of untreated cancerous tissues from different animals even when the tumours are produced from the same parent tumour, it is evident that only very large differences between the degree of glycolysis of the tumours of the injected and the uninjected animals would be significant. Glycolytic values from a number of tumours were compared to give the control figure. The glycolytic value of 5 tumours of the same generation ranged between 31 and 43 mg. lactic acid per g. of tissue, and an average value of 37 mg. was taken for the control figure. The animals were given a subcutaneous injection (on the side opposite the tumour) of 0-2 cc. of 1 % iodoacetic acid (previously neutralised) and were killed from 1 to 2 hours afterwards. Their tumours were removed, sliced and put into sugar-containing bicarbonate Ringer’s solution, and the experiment was run as already described. Animals A and B, killed respectively 1 and 2 hours after injection of iodoacetic acid, appeared to be normal and showed no symptoms of iodoacetic acid poisoning. Animal C, on the other hand, was almost moribund when killed 2 hours after injection. 1 In the figures given in the tables this amount of preformed lactic acid has already been subtracted from the values both for the control solutions and those containing iodoacetic acid.