Worm Breeder's Gazette 7(1): 96

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Sodium Azide as an Anesthetic

F.K. Nelson

Low concentrations of sodium azide are not lethal to C.  elegans, 
but reversibly anesthetize the worms for viewing under a cover slip 
with Nomarski microscopy.  In my hands, azide treatment does not 
adversely affect the quality of the Nomarski image as does treatment 
with phenoxypropanol.  To mount L1-L3 larvae, the worms are added to a 
5 l drop of 50 M sodium azide on a 5% agar pad.  For L4's and adults, 
a 5 l drop of 100 M azide is used.  The agar pads are prepared as 
described by Sulston and Horvitz (Devel.  Biol.  56:110, 1977).  
Larvae as well as adults can remain in the azide for at least 2 hours 
and recover with no apparent ill-effects when transferred to an NGM 
plate.  Azide is heat-labile, so it must be added to the slide after 
the agar pad has been prepared.  A note of caution: sodium azide has 
been shown to be a mutagen in bacterial, plant and mammalian cell 
culture systems.