328 Transactions. 



17. Pharmacological Eelationship of Tutin. 



Sclimiedeberg (30) placed coriamyrtin in the picrotoxin group of nerve 

 and musc-le poisons. This group is closely allied to the camphor and 

 digitalin groups, which include a number of the strongest non-nitrogenous 

 poisons found in the vegetable kingdom. Other members of the group are 

 circutoxin, a resinous substance derived from the water-hemlock ; oenan- 

 thotoxin, from the Avater-dropwort ; digitaliresin and toxiresin, decom- 

 position products of digitalin and digitalein respectively ; and oleandresin, 

 from oleandrin. These substances, by their action on the medulla ob- 

 longata, all cause general and respiratory convulsions, slowing of the pulse^ 

 and a rise in blood-pressure. 



Tutin, as has been shown, possesses these actions common to the group. 

 Some experiments were made to determine its toxic power as compared 

 with picrotoxin and coriamyrtin (a very small quantity of the latter — 

 11 mlgm. — dissolved in absolute alcohol was kindly supplied by Mr. Aston, 

 of the Agricultural Department of the New Zealand Government ; he. in 

 turn, had obtained it from its discoverer, Monsieur Riban). 



Ttitin compared with Picrotoxin. — In the experiments on fishes already 



cited it was found that picrotoxin was more lethal than tutin when equal 



percentages of the two were used, and in equimolecular solutions it proved 



much more lethal. In mammals, on the other hand, tutin was found to be 



more fatal than picrotoxin. In Exp. 4 a cat received 0-375 mlgm. per 



kilo of tutin ; it developed severe symptoms, but recovered. Two days 



later it received exactly the same weight of picrotoxin (Exp. 168) without 



the development of any symptoms. The solution of picrotoxin used had 



been made seven months previously, and, lest it had deteriorated, a fresh 



solution was made and the same dose repeated five days later (Ex. 169) ; 



beyond defsecation and occasional swallowing-movements, no symptoms 



appeared. It was therefore concluded that tutin was more poisonous to 



mammals than picrotoxin. Following the procedure adopted in the case 



of fishes, the two were then compared in equimolecular strengths, and 



883 

 0*375 X — mlgm. per kilo given hypodermicallv to the same cat (Exp. 170). 

 336 



It developed twitching, vomiting, and other symptoms resembling those 

 seen with tutin. Only one general convulsion occurred, however, whereas 

 the dose of tutin had caused very numerous convulsions. It recovered in 

 a shorter time, and the whole effect was much less severe ; so that, in con- 

 tradistinction to fishes, mammals may be said to be more susceptible to 

 poisoning by tutin than by picrotoxin. 



Tutin and Coriamyrtin. — The quantity of coriamyrtin mentioned above 

 was insufficient for an extended series of experiments, and only one cat 

 was subjected to its influence (Exp. 171). The symptoms were very similar 

 to those of tutin poisoning ; twitching and convulsions were very marked. 

 In the convulsions the tonic spasms were not so prolonged as in the case 

 of tutin, the clonic element being more in evidence ; emprosthotonos 

 appeared instead of the opisthotonos, which is so invariable a feature of 

 tutin convulsions. Salivation, vomiting, respiration, erection of hairs of 

 tail, and dilatation of the pupil were all present, as in turin poisoning. A 

 strict comparison of its toxic power can hardly be drawn from one case ; 

 but if the time taken to kill be proportional to the toxic power, tutin is the 

 more lethal of the two, for 3 mlgm. per kilo of tutin killed a cat (Exp. 1) in 

 thirty-one minutes, while this cat with the same dose of coriamyrtin died 

 in forty-two minutes. 



