Resistance of the Egyptian mongoose to sarafotoxins.
The Egyptian mongoose (Herpestes ichneumon) is known for its resistance to viperid and elapid venoms. The current work demonstrates that it is also resistant to the venom of Atractaspis and its most toxic component, sarafotoxin-b. Intravenous administration of this toxin, at a dose of about 13 times LD100 for mice, resulted in disturbance in electrocardiograms in the mongoose, which returned to normal after several hours. Sarafotoxin-b failed to induce contraction of mongoose aortal preparations. Endothelin-1, which was demonstrated in tissue extracts of the mongoose by immunological methods, induced contraction of the isolated mongoose aorta. This contraction, however, was greatly reduced when endothelin-1 was applied on top of sarafotoxin-b. Binding studies revealed endothelin/sarafotoxin-specific binding sites in brain and cardiovascular preparations of the mongoose. It is suggested that some structural features of endothelin/sarafotoxin receptors in the mongoose enable them to differentiate between the two peptides.
Bdolah
A
A
Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Israel.
Kochva
E
E
Ovadia
M
M
Kinamon
S
S
Wollberg
Z
Z
D000818:Animals; D004351:Drug Resistance; D004562:Electrocardiography / Q000187:drug effects; D019332:Endothelin-1 / Q000494:pharmacology*; D008988:Herpestidae; D066298:In Vitro Techniques; D008297:Male; D011485:Protein Binding; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014757:Viper Venoms / Q000737:chemistry* / Q000494:pharmacology*
D019332:Endothelin-1; D014662:Vasoconstrictor Agents; D014757:Viper Venoms; C057354:sarafotoxins s6