PHYSIOLOGY OF PEPSIN-FORMING GLANDS. 
695 
In each of the animals studied we have seen that the amount of pepsin contained 
by any part of the stomach (or of the pepsin-forming region) is directly proportional 
to the amount of granules contained by the gland-cells of that part. 
In each of the animals studied we have seen that the cell-granules diminish in 
number and size during digestion. Grutz inter found in the animals'"' investigated by 
him a diminution, during digestion, in the amount of pepsin contained by a definite 
weight of the stomach. Without examining in detail the amount of pepsin contained 
by the gland-cells at different digestive stages, we have seen above in each of the 
animals considered that a definite weight of gastric mucous membrane taken at a 
stage of digestion when the granules are markedly diminished contains a markedly 
diminished amount of pepsin. 
Further, we have seen that during fasting the number of granules contained by the 
gland-cells diminishes, and we know from GRUTZNEii’st experiments that during 
fasting the amount of pepsin contained by a definite weight of gastric mucous mem¬ 
brane diminishes. 
Lastly, it has been shown by Sewall and myselff that in the Rabbit the amount of 
pepsin contained by any portion of tire stomach is in direct proportion to the number 
of granules contained by the “chief” cells of that portion in the living state. 
Hence, then, in all the cases which have been investigated the amount of pepsin is 
in direct proportion to the amount of granules. From this, I think, we may fairly 
conclude that the granules in the gland-cells give rise to pepsin. We have at least 
as much reason to conclude this as we have to conclude that granules in the pancreatic 
gland-cells give rise to trypsin. 
It may, however, be said that since the cells diminish in size during secretion, the 
diminution in the amount of ferment might be caused by a diminution in the cell- 
substance and not in the granules. The following consideration will, I think, show 
that this cannot be the case. Although each gland-cell becomes smaller, there is in 
most cases no obvious diminution, and in some there seems to be an actual increase in 
the amount of cell-substance. The removal of the granules alone is sufficient to cause 
the diminution observed in the size of the cell. Further, since the glands are smaller, 
to obtain an equal weight of resting and of digesting mucous membrane, a larger area 
of the latter, i.e., a greater number of glands, must be taken. 
* Grutzner, Neue Unters. ti. s. w., § 36 et seq., Dog, Pig, Rabbit, and Cat. Pfluger’s Archiv. 
Bd. xvi., 1878, § 118, Dog ; § 120, Oesophagus of Frog. 
f Grutzner, Neue Unters. u. s. w., § 52, Rabbit; § 61, Dog, Cat. Pfluger’s Arcliiv., Bd. is., 1879, 
§ 407 and 408, Oesophagus of Frog. 
+ Journal of Physiol., vol. ii., p. 291, et seq., 1879. I may mention that the arrangement of the 
gastric glands in the Guinea-pig is similar in main points to the arrangement described by Sewall and 
myself as existing in the Rabbit. 
