METHYLALCOHOL IN TUE MOUSE 



843 



at the same hour of the day and emotional disturbances of the animals 

 are largely avoided. Trying to evade their cage, the animals perform 

 muscular exercises which may result in an additional COg formation. 

 In the experiment, the results of which are plotted in Fig. 1, the 

 variations in the amount of exhaled COg were unusually low; the 6 mice 

 of 14.7 gm mean weight exhaled in the 3 experiments (two with controls 

 and one with exposed animals) in the course of 5 min an average amount 

 of COg amounting to 34.9, 35.1 and 34.8 mgm, respectively. 



. = Group of mice injected and CO2 collected Dec 12 

 + = Same group of mice injected and COacollected Dec 13 

 ° " «^y^^u5''°^P of mice injected andCOjcollected Dec 14 

 After being exposed shortly before to 1500 r. ' ' 



o 

 <u 



Q. 



in 



<u 

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80 



70- 



60- 



50 



40 



30- 



20- 



10 





•?9 



— I — I — I — I — I — t — \ — 1 — I — I I i 



10 20 30 40 50 60 70 60 90 100 IIO 120 



Time, mm. 



Fig. 1. Effect of exposure to 1500 r of X-rays on the amount 

 of ^^COg exhaled by a group of mice injected with a "tracer dose" 



of labelled methyl alcohol. 



After a maximum value, 21 minutes following the injection of methanol, 

 the specific activity of the exhalatory COg declines to 1/4 of that value 

 in the course of further 77 minutes. In other experiments this decrease 

 was found to take 73 to 81 minutes. After the lapse of 19 hours the 

 specific activity declined to 0.3 per cent of its maximum value. As seen 

 from Fig. 1 exposure to 1500 r did thus not influence significantly the 

 combustion rate of small amounts of administered methanol. 



The experiments described hitherto were carried out in an almost 

 physiological milieu. We then administered large amounts of methanol, 

 8 mgm to each animal, thus creating strongly unphysiological conditions. 

 These experiments were carried out to test whether a strong shift of 

 the ratio substrates enzyme in favour of the substrate causes a depression 

 of the combustion rate of methanol due to exposure of the animals to 

 X-rays. 



In one group of experiments we injected 8 mgm methanol to each mouse 

 and collected the expiratory ^^COg for 5 hr. After the lapse of a day, the 

 specific activity of the expiratory carbon declined to 2 per cent of the 



