On the nature and action of coelenterate toxins 295 



(1954 a) have reported the presence of a histamine releaser in alcohol extracts of sea 

 anemone tentacles. These same authors (1954 b) find that histamine and 5-HT are 

 components of the venom of the common European wasp, Vcspa Yu/i^aris. 



At the Plymouth Laboratory in the summer of 1953, 5-HT (in the form of the double 

 sulphate with creatinine)* was injected into a series of Portunus depurator. The 

 amounts varied by a factor of ten from 0001 mg to 01 mg 5-HT per crab. All 

 concentrations produced excitation, as seen in constant movements of walking legs and 

 chelae, with twitching of legs and rapid movements of the pincers. The larger the dose, 

 the more severe were the symptoms. However, this was not followed by paralysis, 

 and within one to two hours the crabs appeared normal. While 5-HT may be respon- 

 sible for some of the activity of coelenterate toxin, it is clearly not the crustacean- 

 paralyzing factor. When coelenterates are feeding on animals other than crustaceans, 

 it is conceivable that 5-HT could act as a relaxing agent, since it has been found to 

 relax certain molluscan muscle (Twarog, 1954). 



Some of our chromatograms have given a spot which reacts as an indole amine 

 but which has an Rf value differing from that of 5-HT. It is possible that more than 

 one indole amine exists in coelenterates, as is the case in the skin of certain amphibians 

 (Erspamer, 1954). 



(b) Chromatographic evidence for the presence of quaternary ammonium bases in 

 tentacle extracts 



Methods outlined by Whittaker and Wijesundera (1952) and Bregoff, Roberts 

 and Delw^iche (1953) for the chromatography of quaternary ammonium bases were 

 used in an attempt to determine whether or not tetramethylammonium (Me4N) (or a 

 derivative) was present in extracts of Metridium and Physalia tentacles. This led to a 

 more extended study than was originally contemplated. The results to date will be 

 briefly summarized. 



Various methods were used to separate quaternary ammonium bases from other 

 materials in acetone extracts of Metridium and Physalia tentacles. These partially 

 purified bases were placed on paper and chromatographed with a variety of solvents. 

 Ultraviolet absorption and chemical reagents were used to locate the spots. All 

 procedures gave evidence of two or more quaternary ammonium bases present in the 

 extracts in relatively very large amounts. Often only one large spot would be obtained, 

 and added substances, such as Ach or MciN, would run with the unknowns rather 

 than separately, thus suggesting a complex of related materials with a carrier substance. 

 When certain areas were eluted and assayed on the Venus heart, the eluates inhibited 

 the beat as does Me4N, Ach or other quaternary ammonium base with two or more 

 methyl groups on the quaternary nitrogen. The action of these eluates was antagonized 

 by EtiN and Mytolon (cf. Welsh and Taub, 1953). 



We have tentatively identified one of the bases in the extracts as murexine or uro- 

 canylcholine. This quaternary ammonium base was found in large amounts in the 

 hypobranchial glands of the Mediterranean snail, Murc.x, by Erspamer (1948). It 

 was chemically identified by Erspamer and Benati (1953) after synthesis by Pasini, 

 Vercellone and Erspamer (1952). A generous sample of synthetic urocanylcholine 

 has recently been received from Dr. Pasini. It should make possible certain identifica- 

 tion of the material in the extract, which is clearly a quaternary ammonium base with 



* Kindly supplied by Dr. R. K. Richards, Abbott Laboratories. 



