Creatin and creatinin / by Edward Mellanby.

  • Edward Mellanby
Date:
[1908?]
Catalogue details

Licence: In copyright

Credit: Creatin and creatinin / by Edward Mellanby. Source: Wellcome Collection.

    14/42 page 460
    Weight of muscle ground up Creatinin estimated (from creatin) A 37*5 grs. •235 p.c.‘ B 34-6 •239 Three days survival • C 47-8 •220 D 42*3 •222 m oxygen. E 45*2 •217 F 43-0 •222 Control muscles. Gr 37-3 •235 The muscles were quite irritable after the three days survival. The amounts of creatinin estimated in these frogs are low. Possibly the time of year influences the creatin in the muscle to some extent. The experiments on rabbits differ from the experiments on frogs, in that here the blood supply to the muscles was intact during the time of stimulation, while with the frogs the legs were isolated. Exp. 71. Rabbit. The sciatic nerve on one side was dissected out as near the cord as possible, cut and the peripheral end stimulated discontinuously for 1^ hours: the first hour the nerve was stimulated for 10 minutes and allowed to rest 5 minutes. After this, stimu- lation last 3 minutes and rest 1 minute. The creatin contents of the resting and stimulated limbs were compared. W eights of Creatinin muscle found A 95*9 grs. •448 p.c. Control (leg muscle). B 26*5 •435 Control (back muscle). C 109-7 •436 Stimulated muscle. Exp. 81. Rabbit. Both sciatic nerves were cut and the peripheral ends stimulated for two hours 2. The creatinin (from creatin) estimated in a portion directly by the colorimetric method — *430 per cent. Control resting muscle =-440 per cent. It is clear from these two experiments on the intact muscle of rabbits that great muscular contraction does not influence the creatin content of mammalian muscle. From a general consideration of all the above results it is seen: (1) That the performance of muscular work leaves creatin unaffected. (2) That the survival of frog’s isolated muscle, even for three days, does not increase the creatin content of muscle. 1 These experiments were kindly done by Mr V. J. Woolley of King’s College, Cam¬ bridge, and Dr H. K. Anderson, respectively. 2 The observations on the absence of creatinin in fatigued muscle given on page 457 <r were made on this rabbit.
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