Edematogenic Activity of Scorpion Venoms from the Buthidae Family and the Role of Platelet-Activating Factor and Nitric Oxide in Paw Edema Induced by Tityus Venoms

Abstract

We compared the edematogenic activity of venoms of scorpions from the Buthidae family, Tityus bahiensis (Tbv), Tityus serrulatus (Tsv) and Rhopalurus rochai (Rrv). Three doses (20, 40 and 80 microg/kg sc) of each venom were administrated in hind paw of mice and edema was measured from 5 min to 24 h. Tbv and Tsv both induced edema of rapid onset (135% of increase at 15 min); Rrv induced only a mild edema (40% of increase). We then investigated the involvement of platelet-activating factor (PAF) and endogenous nitric oxide (NO) in Tbv and Tsv-induced paw edema. Pretreatment of mice with a PAF antagonist (WEB-2170) inhibited Tsv but not Tbv-induced edema. Pretreatment with a non selective inhibitor of NO-synthases (L: -NAME) inhibited or increased the edema depending on the dose and the time the edema was measured. In conclusion, the venoms from Tityus are stronger inducers of edema than the venom from the Rhopalurus scorpion. The venoms of Tityus species are similar in potency and time-course edema development. PAF is involved in the edema induced only by Tsv.

In Vivo Detection of Macrophage Recruitment in Hind-Limb Ischemia Using a Targeted Near-Infrared Fluorophore

“…5e–h), further confirming the identity of these cells as inflammatory macrophages. Massive macrophage recruitment was seen mainly in the dermis for the paw inflammation model and in the connective tissue surrounding the femoral artery for the hind-limb ischemia model, in accordance with previous reports [10], [30].…”

Effects of a toxin isolated from Tityus bahiensis scorpion venom on the hippocampus of rats

“…T. serrulatus is the best studied, and most of the scorpion data in the literature are about its venom and toxins. Almost nothing is known about the venom of other Brazilian scorpions from the family Buthidae (Severino et al, 2009). Concerning T. bahiensis scorpion venom, Lourenço et al (2002) reported that some of its fractions caused convulsion, even more intense than that evoked by T. serrulatus venom when injected directly into the hippocampus.…”

The transcriptome recipe for the venom cocktail of Tityus bahiensis scorpion

“…The clinical manifestations induced by a T. bahiensis sting in humans are local pain, cardiovascular manifestations (including changes in blood pressure) and respiratory failure (Bucaretchi et al, 2014). A scorpion sting is especially fatal for infant victims (Ismail, 1995;Severino et al, 2009). Lorenço et al (2002) estimated the LD50 of T. bahiensis venom in mice to be around 1.18 mg/kg.…”