1899-1900.] Dr J. S. M'Kendrick on Enzymes in Tissues. 81 
that case reduced Fehling. Again, it is not probable that putre- 
factive organisms have had to do with this result, as in that case 
one would have expected something akin to tryptic digestion, 
which was always absent. Is there a special organism in this 
disease which has such a power, or, do the results depend upon 
the liberation of enzymes from the tissues in a greater abundance 
than exist normally ? The tubercular sputum has a faint reaction 
in the conversion of starch. This result probably depends upon 
an organised ferment that is liberated after death from the 
pyogenic organisms which are present in such a sputum, or it 
may depend upon ptyalin in the saliva. 
( b ) What is their Action on Fibrin in a Watery 
Solution ? 
All tissues (normal and pathological) behave alike in yielding 
extracts which, with water alone, cause no change in fibrin ; and 
when the solution is filtered and tested with sulphate of ammonium 
there is no precipitate which shows the presence of proteoses. 
(c) What is their Action on Fibrin in an Acid 
Solution ? 
All the normal and pathological tissues have the power of more 
or less dissolving fibrin in a 0*2 per cent. TIC1 solution, and of 
yielding a solution of peptones which give the biuret reaction.* 
The following tissue extracts have the power of dissolving fibrin 
more markedly than the others 
Rabbit. 
Child. 
Adult. 
Post-mortem. 
Pathological. 
Small Intes- 
tine 
Stomach 
Lungs 
Liver 
Muscle 
Large Intes- 
tine 
Stomach 
Lungs 
Liver 
Muscle 
Muscle 
Lung 
Liver 
Muscle 
* This result cannot be due to the conversion of proteids into albuminoses, 
etc., by the acid itself, as fibrin subjected to the action of 40 c.c. of 0 - 2 per cent. 
HC1 alone causes it to swell up, but not to be dissolved. 
VOL. XXIII. F 
