TOXICOLOGY AND PHARMACOLOGY 413 



We must therefore strive to discover what facts speak for a 

 strengthening of peristalsis by such salts. 



Interesting observations by MACCALLUM* in agreement with 

 observations by J. LOEB * 2 show, as a matter of fact, that the salts 

 of Group I exert on muscle and nerve a stimulating effect which 

 induces an increased peristalsis of the intestines. This occurs not 

 only when citrates, tartrates and sulphates are placed in the lumen 

 of the intestine but also when they are injected subcutaneously or 



intravenously, and even dropping a -^ solution of such salts on the 



o 



peritoneal surface of the intestines induces especially strong peris- 

 taltic intestinal movement, so that according to Wo. PAULI* S the 

 intestinal activity may even approach that of a gastro-enteritis. 

 With this increase of peristalsis there is associated an active secre- 

 tion into the intestine, so that according to MACCALLUM the empty 

 coils of small intestine of a rabbit became filled with secretion 

 (20 c.c.) when a drop of sodium citrate solution was placed on the 

 peritoneal coat. I wish to recall that those anions raise the blood 

 pressure, and possibly the increased secretory activity stands in 

 relation to this. 



Magnesium sulphate is one of the best known cathartics, although 

 on account of its place in Group III of our table we would hardly 

 expect that it should have any special action. This need not surprise 

 us, since there are in the intestine Na ions which largely inhibit the 

 antagonistic action of Mg ions, and as a result the SO 4 action is 

 brought out. According to MACCALLUM, if we introduce MgCl2 

 (instead of MgS0 4 ) or CaCl2 solution into the intestine, or inject 

 them into the circulation, the peristal ic waves which citrates or 

 fluorids, for instance, strongly induce, are inhibited. This agrees 

 completely with our premises, according to which there exists high 

 antagonistic action of divalent cations (see p. 82) as here exemplified. 

 CaCl 2 diminishes diuresis as well as defecation. 



FRANKL * and AUER * found certain contradictions to the results 

 of MACCALLUM. They claim to have observed no diarrhea upon 

 injecting subcutaneously or intravenously dilute purgative salts, and 

 to have observed even constipation upon employing more concen- 

 trated solutions. J. BANCROFT,* on the contrary, confirms the results 

 of MACCALLUM. From all of which it may be concluded that, as 

 was to be expected, the result chiefly depends upon the conditions 

 of concentration and upon the location where these conditions are 

 active. In this connection the old experiments of VON HAY* are 

 very instructive. If he gave large quantities of sodium sulphate by 

 mouth, it abstracted fluid until its concentration had fallen to 3 per 



