BACTERIAL POISONS 41 



cardiac death in spite of artificial respiration. These manifestations 

 seem to have a central origin, with particular action upon the vagi 

 and the phrenic nerves. Apparently also the localization of the 

 diphtheritic lesion may influence the selection of individual nerves, 

 the most concentrated action taking place upon the nerves whose 

 endings are distributed in this particular region, for, as Meyer and 

 Ransom 35 have shown, this poison, like tetanus toxin, may be ab- 

 sorbed into the nerves directly through the nerve endings. An in- 

 teresting selective action also of diphtheria poison is the apparently 

 specific alteration of the suprarenal glands which is regularly no- 

 ticed, as enlargement and congestion, in diphtheria-infected guinea 

 pigs, and which has been associated by many workers with the char- 

 acteristic drop in blood pressure which accompanies all severe cases 

 of the disease. Abramow 36 has studied this lesion particularly, and 

 believes that it consists in a degeneration and final disappearance of 

 the chromaffin substance and of the medullary cells. He believes 

 that this, together with degeneration of the heart muscle itself, is of 

 great importance in causing the characteristic vascular failure. 



In botulinus poisoning there is, as Marinesco B7 and Kempner 

 and Pollack 38 have shown, a direct effect upon the cells of the an- 

 terior horns with degenerative changes in the Nissl granules. 



Tetanus poison, which has been studied extensively by pharma- 

 cologists, shows a very marked affinity for the nervous system, as, in 

 fact, the symptoms of tetanus indicate. Indeed, while many of the 

 bacterial poisons are distributed by the blood stream to the point of 

 final attack, in tetanus the absorption of the toxin from the lesion or 

 the point of injection takes place entirely by the path of the nerves. 



That this method of poison distribution might be, among others, 

 an important one was suggested as early as 1892 by Bruschettini, 39 

 who found tetanus toxin in the nerves but not in the adjacent muscle 

 and other tissues surrounding the point of subcutaneous injection. 

 Similar results were obtained subsequently by Hans Meyer, whose 

 experiments were confirmed and extended by Marie and Morax. 40 

 Finally Meyer and Ransom 41 furnished complete proof that the 

 pojson was absorbed from the blood and tissues by the peripheral 

 nerve endings alone and was transported centripetally only by the 

 paths of the neurons. The experimental facts elicited may be sum- 

 marized as follows : 



35 Meyer and Ransom. Arch, de pharmacodyn., Vol. 15, 1905, also Meyer, 

 Berl klin. Woch., 25 and 26, 1909, also Arch. f. exp. Path. u. Ther., Vol. 

 60, 1909. 



36 Abramow. Zeitschr. f. 1mm., Vol. 15, 1912. 



37 Marinesco. Compt. rend, de la soc. de biol., Vol. 3, 1896. 



38 Kempner and Pollack. Deutsche med. Woch., 32, 1897. 



39 Bruschettini. Riforma medica, 1892. 



40 Marie and Morax. Ann. de I'Inst. Past., 1902. 



41 Meyer and Ransom. Archiv f. exp. Path. u. Pharm., 49, 1903. 



