Black Widow Spider Neurotoxins

BilZ0r BilZ0r at TAKETHISOUThotmail.com
Sat Sep 18 19:20:55 EST 2004

curious11112001 at yahoo.com (Curious) wrote in 
news:34a4f456.0409181256.22281d1d at posting.google.com:

> What symptoms would I experience if poisons from the Black Widow
> Spider was "fed" directly into the CNS neurons that make up my
> motor cortex?

What a very interesting toxin Black Widows have:

It would seem to me it would cause seizures. 

Annu Rev Neurosci. 2001;24:933-62.

alpha-Latrotoxin and its receptors: neurexins and CIRL/latrophilins.

Sudhof TC.

alpha-Latrotoxin, a potent neurotoxin from black widow spider venom, 
triggers synaptic vesicle exocytosis from presynaptic nerve terminals. 
alpha-Latrotoxin is a large protein toxin (120 kDa) that contains 22 
ankyrin repeats. In stimulating exocytosis, alpha-latrotoxin binds to two 
distinct families of neuronal cell-surface receptors, neurexins and CLs 
(Cirl/latrophilins), which probably have a physiological function in 
synaptic cell adhesion. Binding of alpha-latrotoxin to these receptors 
does not in itself trigger exocytosis but serves to recruit the toxin to 
the synapse. Receptor-bound alpha-latrotoxin then inserts into the 
presynaptic plasma membrane to stimulate exocytosis by two distinct 
transmitter-specific mechanisms. Exocytosis of classical 
neurotransmitters (glutamate, GABA, acetylcholine) is induced in a 
calcium-independent manner by a direct intracellular action of alpha-
latrotoxin, while exocytosis of catecholamines requires extracellular 
calcium. Elucidation of precisely how alpha-latrotoxin works is likely to 
provide major insight into how synaptic vesicle exocytosis is regulated, 
and how the release machineries of classical and catecholaminergic 
neurotransmitters differ.

More information about the Neur-sci mailing list

Send comments to us at biosci-help [At] net.bio.net