ABSTRACT
Spider venom is a rich source of potential probes for ion channels and receptors in nerve cells (Grasso, 1988; Jakson and Parks, 1989; Kawai and Nakajima, 1993). In this article we wish to summarise the purification procedure, the properties and describe the biological effects shown by one of the toxins present in the venom glands of the spider of the family of Therididae, belonging to the genus Latrodectus. This article is not intended to be comprehensive. Several publications (Maretic and Lebez, 1979; Newlands, 1987; Southcott, 1978; Sutherland, 1990) and reviews (Wong et al., 1987; Newlands and Atkinson, 1988; Atkinson and Wright, 1992) are available to readers needing more information on the signs and symptoms of Latrodectus poisoning as well as on the biology of spiders of medical importance. These aspects are, therefore, not treated in detail here. However, since one of the toxins present in the venom of Latrodectus, is used extensively in neurobiology to characterise the toxin-binding sites present in the nerve cells, to study the mechanisms of exocytosis and to improve our knowledge of pre-synaptic organisation, we consider it useful to spend a little time, to briefly introduce the spider and the syndrome caused by its bite, to the reader.
