Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 24 September 1976:
Vol. 193. no. 4259, pp. 1256 - 1258
DOI: 10.1126/science.785600
Prev | Table of Contents | Next

Articles

Science, Vol 193, Issue 4259, 1256-1258
Copyright © 1976 by American Association for the Advancement of Science

articles

Botulinum toxin: mechanism of presynaptic blockade

I Kao, DB Drachman, and DL Price

The mechanism of action of botulinum toxin was analyzed by the use of calcium ionophores and black widow spider venom. Addition of calcium ionophores to nerve-muscle preparations blocked by botulinum toxin did not increase the frequency of miniature end plate potentials. However, the spider venom elicited a barrage of miniature end plate potentials after blockade by botulinum. Electron micrographs of preparations treated with botulinum toxin and then the spider venom revealed clumping of synaptic vesicles at release sites in the otherwise depleted nerve terminals. These findings indicate that the action of botulinum toxin is not due to deficient storage of acetylcholine in vesicles or blockade of calcium entry into nerve terminals. They suggest that the toxin interferes with the acetylcholine release process itself, possibly by blocking exocytosis at the release sites.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Impairment of Synaptic Vesicle Exocytosis and Recycling During Neuromuscular Weakness Produced in Mice by 2,4-Dithiobiuret.
Y.-F. Xu, D. Autio, M. B. Rheuben, and W. D. Atchison (2002)
J Neurophysiol 88, 3243-3258
   Abstract »    Full Text »    PDF »
Open-Label Study of Botulinum Toxin for Upper Limb Spasticity in Cerebral Palsy.
V. Wong, A. Ng, and P. Sit (2002)
J Child Neurol 17, 138-142
   Abstract »    PDF »
Presentation of myasthenia gravis mimicking blepharospasm.
M. E. Roberts, M. J. Steiger, and I. K. Hart (2002)
Neurology 58, 150-151
   Full Text »    PDF »
Neuromuscular Blockade in the Management of Cerebral Palsy.
L. A. Koman, J. F. Mooney III, and B. P. Smith (1996)
J Child Neurol 11, S23-S28
   Abstract »    PDF »
Topical Review: Electrodiagnosis of Infantile Botulism.
A. R. Gutierrez, J. Bodensteiner, and L. Gutmann (1994)
J Child Neurol 9, 362-366
   Abstract »    PDF »
Infant Botulism: A Review of the Literature.
J. M. Wigginton and P. Thill (1993)
Clinical Pediatrics 32, 669-674
   PDF »
Neurexins.
M. Geppert, Y.A. Ushkaryov, Y. Hata, B. Davletov, A.G. Petrenko, and T.C. Sudhof (1992)
Cold Spring Harb Symp Quant Biol 57, 483-490
   Abstract »    PDF »
Botulinum Toxin in the Management of Blepharospasm.
J. J. Dutton and E. G. Buckley (1986)
Arch Neurol 43, 380-382
   Abstract »    PDF »
Treatment of Blepharospasm With Botulinum Toxin: A Preliminary Report.
B. R. Frueh, D. P. Felt, T. H. Wojno, and D. C. Musch (1984)
Arch Ophthalmol 102, 1464-1468
   Abstract »    PDF »
Susceptibility of skeletal muscle to Coxsackie A2 virus infection: effects of botulinum toxin and denervation.
C. Andrew, D. Drachman, A Pestronk, and O Narayan (1984)
Science 223, 714-716
   Abstract »    PDF »
Eaton-Lambert Syndrome in a 9-Year-Old Girl.
E. Chelmicka-Schorr, L. P. Bernstein, E. B. Zurbrugg, and P. R. Huttenlocher (1979)
Arch Neurol 36, 572-574
   Abstract »    PDF »
Motor nerve sprouting and acetylcholine receptors.
A Pestronk and D. Drachman (1978)
Science 199, 1223-1225
   Abstract »    PDF »
The Role of the Synaptic Protein SNAP-25 in the Potency of Botulinum Neurotoxin Type A.
J. E. Keller and E. A. Neale (2001)
J. Biol. Chem. 276, 13476-13482
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)