10 BULLETIN 365^ V. S. DEPARTMENT OF AGEICULTUEE. 



5. The delphinin seems to act successively and with a paralyzing effect upon 

 the general sensitiveness, the reflex power, the respiration, and the coordina- 

 tion of movements. Its favorite place of predilection is the nervous system 

 and it has no influence on the muscular system. 



According to most authors convulsions come on in the later stages 

 of the poisoning, with intervals in which the animal is in a comatose 

 condition. Characteristic of Delphinium poisoning are the muscular 

 tremblings which start in the abdominal muscles and pass over the 

 body. Although most of the authors agree in general on the symp- 

 toms and the anatomical lesions exhibited by animals poisoned by 

 delphinin, there is some disagreement as to the way the poison acts 

 in bringing about the observed results. Several authors have com- 

 pared delphinin to veratrin, and some have compared it to curare, 

 while most of them find that its action is similar to that of its near 

 relative aconitin. It certainly is true that the action of delphinin 

 on experimental animals, as given by most authors, corresponds 

 very closely with the recognized action of aconitin. The principal 

 difference seems to be that delphinin has a direct depressing action 

 on the vasomotor centers of the cord (Boehm and Serck) and that it 

 does not paralyze the heart muscles to any extent (Schiller). Some 

 of the earlier authors attributed the paralysis of Delphinium poison- 

 ing to a paralyzing action on the muscles similar to that caused by 

 veratrin, but it has been established that delphinin exerts its essen- 

 tial action on the nervous system rather than directly on the muscles. 



Rabuteau and some others advance the theory that the paralysis 

 is due, as in the case of curare poisoning, to the paralysis of the 

 motor end organs rather than to a depression of the nerve centers ; 

 while Boehm and Serck describe experiments which show that the 

 preparation of delphinin used by them acted on the motor nerve 

 centers rather than on the end organs. 



The chlorid of the alkaloids in the American Delphiniums has 

 been separated by Lohmann and put upon the market by Merck 

 under the name of Delphocurarine, with the idea that it may be 

 used as a drug instead of curare. This has been discussed in some 

 detail by Heyl, 1903. 



Authors seem to agree that the slowing of the respiratory move- 

 ments and the final asphyxiation are due to depression of the re- 

 spiratory centers in the medulla oblongata and the afferent vagus 

 fibers. Boehm and Serck, 1876, show that death is delayed by using 

 artificial respiration, indicating that asphyxiation is the immediate 

 cause of death rather than the stopping of the heart. They also 

 found that immediately after injections of delphinin, both pulse 

 rate and blood pressure fell, due to the stimulation of the vagus. 

 This is followed by a rise due to paralysis of the vagus through con- 

 tinued action of the poison. If the dose is repeated or if the original 



