Action of Black Widow Spider Venom on an Aminergic Synapse

Nature ◽  
1973 ◽  
Vol 241 (5388) ◽  
pp. 353-354 ◽  
Author(s):  
S. G. CULL-CANDY ◽  
H. NEAL ◽  
P. N. R. USHERWOOD
Keyword(s):  
Spider Venom ◽  
Black Widow ◽  
Black Widow Spider ◽  
Black Widow Spider Venom ◽  
Widow Spider

Properties of spontaneous potentials at denervated motor endplates of the frog

1976 ◽  
Vol 194 (1115) ◽  
pp. 195-210 ◽  
Keyword(s):  
Schwann Cell ◽  
Time Course ◽  
Experimental Treatment ◽  
Spider Venom ◽  
Black Widow ◽  
Motor Endplates ◽  
Black Widow Spider ◽  
Ringer’S Solution ◽  
Black Widow Spider Venom ◽  
Widow Spider

Some properties of spontaneous miniature potentials at denervated frog motor endplates (Schwann cell-min. e. p. ps) have been investigated. Schwann cell-min. e. p. ps showed a slower and more variable time course than min. e. p. ps at inneryated endplates. The occurrence of Schwann cell-min. e. p. ps usually obeyed Poisson statistics and in the absence of experimental treatment their mean frequency remained stable for several hours. Schwann cell-min. e. p. p. frequency increased with increasing temperature. A logarithmic relation was observed with a mean Q 10 of 4.87 ± 0.37. In other experiments a Q 10 of 9.50 ± 0.63 was found for min. e. p. ps at innervated endplates. Lanthanum and manganese ions, black widow spider venom, ethanol, diamide, ouabain, theophylline and acid Ringer’s solution, all of which increased normal min. e. p. p. frequency, failed to raise the frequency of Schwann cell-min. e. p. ps. Lanthanum, ethanol, ouabain and low pH depressed the frequency, while black widow spider venom, diamide, theophyline and manganese were without significant effect. Adenosine, which depresses min. e. p. p. frequency at innervated endplates, had no effect on spontaneous miniature potentials at denervated endplates. Removal of Ca 2+ from the external medium reduced the frequency of Schwann min. e. p. ps; and a decrease was also seen in one experiment where the Ca 2+ concentration was raised from 1.8 to 10 mM. Diluting the Ringer’s solution raised Schwann cell-min. e. p. p. frequency transiently. This increase resulted from a reduction in osmolarity, not in the ionic strength, of the medium.

scholarly journals ACTIVATION OF A NITRERGIC MECHANISM BY BLACK WIDOW SPIDER VENOM AND α-LATROTOXIN

1997 ◽  
Vol 75 ◽  
pp. 33
Author(s):  
C.G Li ◽  
M.J. Rand ◽  
T. Akaike ◽  
M. Yoshida ◽  
H. Maeda
Keyword(s):  
Spider Venom ◽  
Black Widow ◽  
Black Widow Spider ◽  
Black Widow Spider Venom ◽  
Widow Spider

scholarly journals Freeze-fracture studies of frog neuromuscular junctions during intense release of neurotransmitter. I. Effects of black widow spider venom and Ca2+-free solutions on the structure of the active zone.

1979 ◽  
Vol 81 (1) ◽  
pp. 163-177 ◽  
Author(s):  
B Ceccarelli ◽  
F Grohovaz ◽  
W P Hurlbut
Keyword(s):  
Neuromuscular Junctions ◽  
Freeze Fracture ◽  
Spider Venom ◽  
Presynaptic Membrane ◽  
Black Widow ◽  
Black Widow Spider ◽  
Intramembrane Particles ◽  
Black Widow Spider Venom ◽  
Active Zones ◽  
Widow Spider

Black widow spider venom (BWSV) was applied to frog nerve-muscle preparations bathed in Ca2+-containing, or Ca2+-free, solutions and the neuromuscular junctions were studied by the freeze-fracture technique. When BWSV was applied for short periods (10-15 min) in the presence of Ca2+, numerous dimples (P face) or protuberances (E face) appeared on the presynaptive membrane and approximately 86% were located immediately adjacent to the double rows of large intramembrane particles that line the active zones. When BWSV was applied for 1 h in the presence of Ca2+, the nerve terminals were depleted of vesicles, few dimples or protuberances were seen, and the active zones were almost completely disorganized. The P face of the presynaptic membrane still contained large intramembrane particles. When muscles were soaked for 2-3 h in Ca2+-free solutions, the active zones became disorganized, and isolated remnants of the double rows of particles were found scattered over the P face of the presynaptic membrane. When BWSV was applied to these preparations, dimples or protuberances occurred almost exclusively alongside disorganized active zones or alongside dispersed fragments of the active zones. The loss of synaptic vesicles from terminals treated with BWSV probably occurs because BWSV interferes with the endocytosis of vesicle membrane. Therefore, we assume that the dimples or protuberances seen on these terminals identify the sites of exocytosis, and we conclude that exocytosis can occur mostly in the immediate vicinity of the large intramembrane particles. Extracellular Ca2+ seems to be required to maintain the grouping of the large particles into double rows at the active zones, but is not required for these particles to specify the sites of exocytosis.

scholarly journals Insecticidal toxins from black widow spider venom

Toxicon ◽  
2007 ◽  
Vol 49 (4) ◽  
pp. 531-549 ◽  
Author(s):  
A. Rohou ◽  
J. Nield ◽  
Y.A. Ushkaryov
Keyword(s):  
Spider Venom ◽  
Black Widow ◽  
Black Widow Spider ◽  
Insecticidal Toxins ◽  
Black Widow Spider Venom ◽  
Widow Spider
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