Barietin, a snake venom vascular endothelial growth factor from puff adder Bitis arietans venom, increases the heart rate with minor effect on blood pressure in rats

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  Barietin, a snake venom vascular endothelial growth factor from puff adder Bitis arietans venom, increases the heart rate with minor effect on blood pressure in rats ABSTRACT Snake venom vascular endothelial growth factors (svVEGFs) are homodimeric proteins comprising two equal subunits bound by two intermolecular disulfide bonds. The main biological effects of svVEGFs are local vasodilatation, increasing of vascular permeability, and hypotension. Barietin, a svVEGF purified from the venom of puff adder Bitis arietans , differs from other representatives of this toxin family by its shortened C-terminal amino acid sequence. No data about barietin effects on hemodynamics are available. Studying those in rats we found that barietin at a dose of 1 mg/kg significantly increased heart rate, exerting only a minor influence on blood pressure. In this respect, it differs from other svVEGFs having a significant effect on blood pressure. We aimed to find the barietin active fragment which m...

Updated geographical distribution of the family Barychelidae Simon, 1889 from Brazil (Araneae: Mygalomorphae)

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Updated geographical distribution of the family Barychelidae Simon, 1889 from Brazil (Araneae: Mygalomorphae)

Abstract

Spiders of the family Barychelidae, the sister group to Theraphosidae, are mainly concentrated in the Southern Hemisphere. In the Neotropical region, Barychelidae is represented by five genera found in Brazil, Colombia, Cuba, Ecuador, Panama, Peru and Venezuela. Barychelid spiders are known for their sedentary behavior, spending most of their lives in burrows constructed with a hinged trapdoor made of silk and soil. This habit and the difficulty in identifying and locating their camouflaged burrows, poses challenges to obtaining specimens thereby obscuring the group’s true diversity. Examination of numerous specimens from different zoological collections allowed us to expand the distribution of Barychelidae spiders adding 95 new records. In addition to geographic data from colleted material, we were able to find 56 iNaturalist observations of barychelid spiders, with 29 in unpublished locations, totaling 124 new records in Brazil. Overall, the expanded geographical distribution of Barychelidae spiders in Brazil has revealed remarkable diversity, with numerous species covering a variety of habitats. This distribution mapping can provide valuable information for the study of populations variation and evolutionary relationships and help in the biogeographical research of the family Barychelidae.

Gonzalez Filho, Hector Manuel, Pedro Costa, Jean de Paiva, and José Paulo Guadanucci. 2025. “Updated Geographical Distribution of the Family Barychelidae Simon, 1889 from Brazil (Araneae: Mygalomorphae)”. Boletim Do Museu Paraense Emílio Goeldi - Ciências Naturais 19 (3), 1-16. https://boletimcn.museu-goeldi.br/bcnaturais/article/view/1009