alpha-latrotoxin of black widow spider venom depolarizes the plasma membrane, induces massive calcium influx, and stimulates transmitter release in guinea pig brain synaptosomes.
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چکیده
منابع مشابه
Release of neurotransmitters and depletion of synaptic vesicles in cerebral cortex slices by alpha-latrotoxin from black widow spider venom.
The effect of alpha-latrotoxin on cerebral cortex slices was studied by both biochemical and morphological methods. This toxin greatly stimulates the release of preloaded gamma-amino[3H]butyric acid from cortex slices. The response increases linearly with dose. The release is not dependent on the presence of extracellular Ca2+, and therefore it is not mediated by the release of other transmitte...
متن کاملMolecular Evolution of α-Latrotoxin, the Exceptionally Potent Vertebrate Neurotoxin in Black Widow Spider Venom
Black widow spiders (members of the genus Latrodectus) are widely feared because of their potent neurotoxic venom. α-Latrotoxin is the vertebrate-specific toxin responsible for the dramatic effects of black widow envenomation. The evolution of this toxin is enigmatic because only two α-latrotoxin sequences are known. In this study, ~4 kb α-latrotoxin sequences and their homologs were characteri...
متن کاملCalcium transport mechanisms in membrane vesicles from guinea pig brain synaptosomes.
Ca2+ transport mechanisms were investigated using membrane vesicles prepared from guinea pig brain synaptosomes by hypotonic lysis. Two major mechanisms of Ca2+ transport exist, Na+-Ca2+ exchange and ATP-dependent Ca2+ uptake. A third although minor component of Ca2+ uptake occurs under hyperpolarizing conditions (determined by increased uptake of [3H]tetraphenylphosphonium+). Na+-Ca2+ exchange...
متن کاملBlack widow spider bite.
These two cases illustrate many classical features of latrodectism. A subclinical bite followed by extensive systemic signs and symptoms in a recognizable pattern is strongly suggestive of the diagnosis. Pain and muscle spasms are refractory to standard therapy but are relieved by intravenous calcium. Finally, there should be complete resolution of the symptoms after only one vial of antivenin ...
متن کاملalpha-Latrotoxin and its receptors: neurexins and CIRL/latrophilins.
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...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1982
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.79.24.7924