Renal- and calcium-dependent vascular effects of Polybia paulista wasp venom

Abstract

Abstract:In the present study, the effects of Polybia paulista venom (PPV) on renal and vascular tissues were investigated. Isolated kidneys perfused with PPV (1 and 3 µg/mL) had increased perfusion pressure, renal vascular resistance , urinary flow, and glomerular filtration rate; and reduced sodium tubular transport. Histological evaluation demonstrated deposits of proteins in Bowman's space and tubular lumen, and focal areas of necrosis. The venom promoted a cytotoxic effect on Madin-Darby canine kidney (MDCK) cells. A significant increase in lactic dehydrogenase levels was observed in response to venom exposure. In isolated mesenteric vascular beds, pressure and vascular resistance augmented in a dose-dependent manner. PPV increased the contractility of aortic rings maintained under basal tension. This contractile response was inhibited when preparations were maintained in Ca 2+ -free medium. Likewise, verapamil, a voltage-gated calcium channel blocker, also inhibited the contractile response. In this study, phentolamine, a blocker of α-adrenergic receptor blocker, significantly reduced the contractile effect of PPV in the aortic ring. In conclusion, PPV produced nephrotoxicity, which suggests a direct effect on necrotic cellular death in renal tubule cells. The vascular contractile effect of PPV appears to involve calcium influx through voltage-gated calcium channels via adrenergic regulation.

Influência de fragmentos florestais sobre a nidificação de vespas sociais (Hymenoptera, Vespidae) em cafeeiro

“…Foram registradas 55 colônias de 20 espécies e sete gêneros de vespas sociais, sendo Polybia paulista (H. von Ihering, 1896), a espécie com maior número de colônias (n = 6) (Tabela 1). Essa espécie é frequente em ambientes naturais (Souza & Prezoto, 2006;Albuquerque et al, 2015), agrícolas (Perioto et al, 2011;Jacques et al, 2015) e sinantrópicos (Canevazzi & Noll, 2011;Vinhote et al, 2011;Jacques et al, 2012;Oliveira et al, 2017), e somado ao fato da mesma predar Leucoptera coffeella (Guérin-Mèneville, 1842) (Lepidoptera, Lyonetiidae), torna a presença dessa espécie valiosa para o controle biológico no café (Fragoso et al, 2001). Tabela 1.…”

Vasoconstrictor effect of Africanized honeybee (Apis mellifera L.) venom on rat aorta

“…This hypothesis is corroborated by Vinhote et al . [ 17 ], who reported such contraction in aortic rings, induced by Polybia paulista wasp venom, showing that the effect was dependent on voltage-operated calcium channels, and that α-adrenergic receptors were involved.…”