Response of the chick ciliary ganglion-iris neuromuscular preparation to botulinum neurotoxin.
Response of the chick ciliary ganglion-iris muscle neuromuscular junction (NMJ) preparation to the botulinum neurotoxin (NT) was investigated. The 150 kDa serotypes A and E NTs inhibited muscle contraction in a dose dependent fashion. Neurotoxicity of type E NT increased 20-40 fold after mild digestion with trypsin. The 50 kDA light and 100 kDa heavy chains of type A NT, following separation, applied individually, did not paralyze the tissues. Preincubation of the NMJ preparations with the isolated type A heavy chain delayed (antagonized) the paralytic action of the 150 kDa dichain type A NT. Sequential administration of type A heavy chain, followed by type A light chain mimicked the action of the parent NT. The chick ciliary preparation therefore is a useful NMJ preparation to study neurotoxicity of botulinum neurotoxins.
Lomneth
R
R
Food Research Institute, University of Wisconsin, Madison 53706.
Suszkiw
J B
JB
DasGupta
B R
BR
D000818:Animals; D001905:Botulinum Toxins / Q000494:pharmacology*; D002645:Chickens; D005726:Ganglia, Parasympathetic / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007498:Iris / Q000166:cytology / Q000294:innervation* / Q000502:physiology; D009469:Neuromuscular Junction / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*
D001905:Botulinum Toxins