Strathprints Home | Open Access | Browse | Search | User area | Copyright | Help | Library Home | SUPrimo

Facilitation of transmitter release by neurotoxins from snake venoms

Harvey, A L and Anderson, A J and Karlsson, E (1984) Facilitation of transmitter release by neurotoxins from snake venoms. Journal de physiologie, 79 (4). pp. 222-227. ISSN 0021-7948

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Toxins C13S1C3 and C13S2C3 from green mamba venom (Dendroaspis angusticeps) acted like dendrotoxin to increase acetylcholine release in response to nerve stimulation in the chick biventer cervicis preparation. Proteins B and E from black mamba venom (Dendroaspis polylepis) had no prejunctional facilitatory activity. All four proteins are trypsin inhibitor homologues. Binding of a prejunctional facilitatory toxin (Polylepis toxin I) to motor nerves was rapid and did not require the presence of Ca2+ or nerve stimulation. Binding was not prevented by protease inhibitors that lacked facilitatory actions. Prejunctional facilitatory toxins also augmented transmitter release in the chick oesophagus and the mouse vas deferens preparations. The effects were rapid in onset and could wane spontaneously. 125I-labelled dendrotoxin bound specifically to rat brain synaptosomes with a KD of about 3 nM. Binding was prevented by native dendrotoxin but not by beta-bungarotoxin or atropine. It is concluded that prejunctional facilitatory toxins affect transmitter release at many types of nerve endings in addition to motor nerve terminals. From consideration of the structures of active and inactive molecules, it is thought that binding of the active toxins may involve several exposed lysine residues.

Item type: Article
ID code: 31698
Keywords: animals, chickens, mice, smooth muscle, neuromuscular junction, neurotoxins, neurotransmitter agents, protease inhibitors, rats, snake venoms, synaptosomes, Pharmacy and materia medica
Subjects: Medicine > Pharmacy and materia medica
Department: Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences
Related URLs:
    Depositing user: Pure Administrator
    Date Deposited: 13 Jul 2011 09:57
    Last modified: 12 Mar 2012 11:28
    URI: http://strathprints.strath.ac.uk/id/eprint/31698

    Actions (login required)

    View Item