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PROFESSOR C. R. MARSHALL ON 



and tetra-methyl-ammonium chloride ; and by Pohl* after the intravenous injection of 

 papaverin-methochloride, papaveraldin-methochloride, and papaverinol-methochloride. 

 None of these substances produced the effect when administered hypodermically. 



As the result of his experiments, Tappeiner came to the conclusion that methyl- 

 phenyl-isoxazol-methochloride stimulated the terminations of the trigeminal nerve, and 

 that the effect produced was, in reality, a Kratschmer-Hering reflex. Thus he found 

 that cocainisation of the nasal mucous membrane prevented the respiratory paralysis ; 

 and that while cocaine administered intravenously also antagonised the action of the 

 isoxazol, the dose required was larger than when the cocaine was applied directly to the 

 nose. The action of tetramethyl-ammonium chloride and the other substances investi- 

 gated by him was explained in the same way. Iodlbauer,'!' who investigated tetramethyl- 

 ammonium chloride more minutely under Tappeiner's direction, came to the same 

 conclusion. Pohl, however, still obtained the characteristic stoppage of the respiration 



Fig. 5. — Effect of 0"01 g. protocatechyl-tropeine hydrochloride intravenously on decerebrate rabbit with both fifth cranial 

 nerves cut. Tracing of respiration taken by connecting one limb of tracheal cannula to a tambour ; other limb left open. 

 Time in seconds. 



after cocainisation of the nose and after division of the ophthalmic branch of the fifth 

 nerves, both in the case of papaveraldin-methochloride and of tetramethyl-ammonium 

 chloride, and he therefore maintains that the action is a central one. The action of 

 protocatechyl-tropeine is also upon the centre. The typical effect on the respiration is 

 still obtained when the brain above the pons is excised and both the fifth cranial nerves 

 are cut within the cranium (fig. 5). Moreover, the same action is obtained in cats 

 (fig. 1), animals in which the typical Kratschmer-Hering reflex is not present. And 

 since the effect on the neuro-muscular system is not coincident in time with the effect 

 on the respiration, the cause of the latter would seem not to be peripheral. It has, 

 however, been shown that the motor nerve endings in the diaphragm may be affected 

 differently, either as regards time or degree, from those of many other voluntary 

 muscles, and it therefore seemed desirable to determine whether the diaphragm played 

 any part in producing the respiratory paralysis. Accordingly, in an anaesthetised 



* Arch. Internat. de Pharmacol., xiii., p. 479 [1904]. 



t Ibid., vii., p. 183 [1900]. 



