THE CURARIFORM ACTION OF DECAMETHYLENE-1 , 10-BISTRIMETHYLAMMONIUM BROMIDE

¹ Wellcome Research Laboratories, Tuckahoe, New York

Confirming the findings of Barlow, Ing, Paton and Zaimis, decamethylene- 1, 10-bis-trimethylammonium bromide (C 10) ‘Syncurine’ brand decamethonium bromide injection, has been found to have a curare-like activity exceeding that of d-tubocurarine chloride, the potency varying with the species and the method of test. It causes less embarrassment of the respiration than d-tubocurarine chloride. In cats and dogs the intravenous injection of C 10 causes no significant change in blood pressure unless a big dose sufficient to depress the respiration is given, in which case a typical asphyxial rise in blood pressure is observed.

The curare-like action of C 10 is not antagonized by neostigmine (Prostigmin) in doses adequate to counteract the effect of d-tubocurarine chloride but, under certain conditions, is antagonized by the corresponding C 5 compound which is virtually devoid of curare-like activity. An interesting finding is the fact that if a dose of C 10 is preceded by a dose of d-tubocurarine chloride, the curarizing action of C 10 is markedly inhibited. The converse does not appear to be the case.

Although C 10 is less toxic than d-tubocurarine chloride in the mouse, this seems to be related to the fact that, in this animal, C 10 displays a relatively weak curarizing action. Rats appear to tolerate well the intraperitoneal injection of repeated, daily curarizing doses of C 10.