The current status and use of botulinum toxins

There are seven different serotypes of botulinum toxin available for study. Each serotype binds to receptor proteins at cholinergic terminals, although there may be different receptor proteins for different serotypes, and each produces a blockade of cholinergic neurotransmission in striated muscle (Martin, 1997; Schiavo et al., 1992; Blasi et al., 1993). The toxins also affect gamma motor neurones serving intrafusal fibres within muscle, thus influencing central neurotransmission (Filippi et al., 1993; Rosales et al., 1996; Modugno et al., 1998), and affecting autonomic terminals on smooth muscles (Albanese et al., 1995). Therefore there are, potentially, a large number of uses for these toxins. The main current uses for the botulinum toxins are reviewed here.