THE ACID OF THE GASTRIC JUICE. 363 
These facta indicate that the formation of hydrochloric acid is a 
process going on in the cell, thai the acid is a cell secretion, and not a 
diffusate from the blood plasma. 
G-amgee's modification of Maly's theory. — Gamgee, 1 while retaining 
the supposition thai the hydrochloric acid is formed by the action of 
the alkaline phosphates on the chlorides, removes the seal of action from 
the blood to the parietal cells. He supposes that those cells possess a 
peculiar selective absorption for the phosphates of sodium, both alkaline 
and acid, and for chlorides, and that within the cell there occur the 
same reactions between these substances as occur in vitro when they 
coexist in solution One of the products of the reaction will then he 
hydrochloric acid, which, in virtue of its high power of diffusion, will 
pass, as soon as formed, into the secretion of the gland. This supposition 
is certainly a step in the right direction, in so far as it brings the seat 
of action to the cell — a much more probable place than the blood — but, 
on the other hand, it assumes a good deal, without overcoming many of 
the objections to Maly's theory. Thus, selective absorption, of both 
alkaline and acid phosphates (probably di- and mono-sodium phosphates) 
is assumed. Unless these are also assumed to he absorbed iti such pro- 
portions that the reaction of the cell contents becomes acid, no formation 
of hydrochloric acid will take place, for, under merely physical conditions, 
no such formation can be demonstrated in vitro. 
Unless, again, the substances selectively absorbed are kept out of 
action in some equally obscure manner by cell activity, there is no 
reason why the secretion of acid should not he continuous ; and if absorp- 
tion of phosphates and chlorides only begins at the commencement of 
digestion, it is not easy to see how the traces of hydrochloric acid, 
formed by such interactions, can keep pace with the demand then made 
for hydrochloric acid. 
Lastly, there is no experimental evidence that there is any such 
selective absorption of phosphates and chlorides by the parietal cells. 
And if a purely physical theory is to he abandoned, and a specific functional 
activity of the cell invoked, there remains no reason for adhering to 
theories which have been evolved on a purely physical basis. 
It is easier, and more in accordance with our notions regarding the 
secretion of other substances, to suppose that the hydrochloric acid 
is formed by cell activity in some metabolic process, from the chlorides 
and organic matters at its disposal. There are an infinite variety of 
such processes capable of taking place, under the varying conditions of 
cell life. It is true we do not know the details of these, nor why such 
processes take place under certain given conditions: nevertheless we 
see the end-results, and there is no reason why hydrochloric acid should 
not also be the end-product of such a cell metabolism rather than the 
product of a kind of specialised diffusion." 2 
1 " Physiological Chemistry," 1S93, vol. ii. p. 113. 
- Hammarsten, "Lehrbuch der physiol. Chem.," Wiesbaden, 1895, Aufl. 3, S. 242. 
See also Heidenhain, Hermann's Handbuch," Bd. v. (1), 8. 151. One such possible process 
is the formation in the cell of an organic acid which does not diffuse away, but is retained 
in the cell and exercises a continuous action on the chlorides, forming hydrochloric acid 
which the cell actively excretes. Another possibility would be the formation during 
•rest of an organic chlorine-containing substance, while the base combined with carbonic 
acid passed into the blood, and the subsequent breaking up during activity of this 
chlorine-compound yielding hydrochloric acid. There are indeed many courses which such 
a cell-metabolism might take yielding hydrochloric acid as an end-result. Sec also Bunge, 
"Lehrbuch der physiol. Chemie," Leipzig, 1891, Aufl. 3, S. 149. 
