It is known by its characteristic warning behaviour of drumming inside the nest when disturbed ( Overal, 1982 and O’Donnell et al., 1997); this website the wasps being very aggressive in defense behaviour and therefore receiving common names such as “seven mile jep” or “guitarron” ( Andena et al., 2009). Synoeca specimens are usually medium-sized, with some species in black colours, such as S. cyanea ( Richards, 1978). The nests are found generally
in tree trunks of urban and rural areas and are usually on a broad inclined surface, attached to the tree trunk by a single sessile comb ( Wenzel, 1998). Until now, there have been no studies regarding the composition and pharmacological activity of S. cyanea venom. In the present study, the effects of S. cyanea selleck chemical venom injection are described for the first time by evaluation of toxicity (LD50), haemolytic, hemorrhagic, and antibacterial activities, and on smooth muscle and oedema assays. Animals were contained in accordance
with the ethical guidelines of the Brazilian Society for Neuroscience and Behaviour, which follows the guidelines for animal care prepared by the Committee on Care and Use of Laboratory Animal Resources, National Research Council, U.S.A. Likewise, every effort was made to avoid unnecessary stress and pain to the experimental animals. The number of animals was kept to the minimum necessary to test the concept. Moreover, the collection of specimens of the wasps was authorized by the Chico Mendes Institute for Biodiversity Conservation of Brazil (license number 21723-1, date of issue 27/10/2009). S. cyanea wasps were collected in Distrito Federal,
Brazil. The wasps’ nest was captured and immediately submitted to low temperature controlled by ice. The nest was stored at −20 °C for 5 h to euthanize the wasps, after which 208 venom sacs were carefully dissected from the wasps, macerated in a 1:1 (v:v) acetonitrile/water solution and centrifuged at 5000 g for 5 min at room temperature. The supernatant was collected, vacuum dried, weighed in a precision balance and stored at −20 °C until use. Males of Swiss albino mice (Mus musculus) of approximately 30 g were used to determine the lethality of S. cyanea whole venom. The venom was dissolved in 120 μL saline solution (0.9%) and injected by i.p. route. Five experimental groups (n = 5 and n = 4 for the 1200 μg/mice group) were tested with Metalloexopeptidase doses 200, 400, 800, 1200 and 1600 μg/30 g mouse. The control group (n = 5) was injected with saline solution. The lethality rate of animals was observed 48 h after inoculation of venom or saline. At the end of the experiment the surviving animals were euthanized with an overdose of sodium pentobarbital (about 75 mg/kg). S. cyanea wasp venom was analyzed for its ability to induce behavioural and physiological changes in mice. For this, all groups of mice that were used in the LD50 determination assay were observed during the first hour of the experiment.