A toxin (Aga-GI) from the venom of the spider Agelenopsis aperta inhibits the mammalian presynaptic Ca2+ channel coupled to glutamate exocytosis.

@article{Pocock1992AT,
  title={A toxin (Aga-GI) from the venom of the spider Agelenopsis aperta inhibits the mammalian presynaptic Ca2+ channel coupled to glutamate exocytosis.},
  author={Jennifer M. Pocock and David G. Nicholls},
  journal={European journal of pharmacology},
  year={1992},
  volume={226 4},
  pages={343-50}
}
Venom of the funnel web spider Agelenopsis aperta was fractionated and screened for activity against the mammalian presynaptic, voltage-dependent Ca2+ channel coupled to glutamate exocytosis. A purified toxin (Aga-GI) from this venom inhibits glutamate exocytosis evoked by elevated potassium or by 4-aminopyridine but is without effect on ionomycin-evoked release. At the same time a partial inhibition of the depolarisation-evoked elevation of cytoplasmic free Ca2+ is seen. The toxin does not… CONTINUE READING