To further explain lung lesions in TOX mice, possibly conjugated MCYST-LR reached the lungs and/or free MCYST-LR got to the lungs in very low concentrations that could not be measured. This study shows that both lung and liver are clearly affected by MCYST-LR, even at sub-lethal doses. The exposure of animals and humans to low doses in water is certainly more frequent than the lethal intoxication (Nobre et al., 2003 and Kugibida et al.,
Doramapimod supplier 2008). Thus, our mice were intraperitoneally exposed to 40 μg/kg of MCYST-LR to mimic a putative human contact with this toxin (Picanço et al., 2004 and Soares et al., 2007). This sub-lethal dose already used in previous studies resulted in mechanical and histological impairment as soon as 2 h after intraperitoneal administration of MCYST-LR in Swiss mice; furthermore, these changes persisted for 4 days being the highest percentage of collapsed lung airspaces detected at 8 h after MCYST-LR injection (Soares et al., 2007). We conclude that treatment with LASSBio 596 per os was effective to avoid pulmonary functional and structural changes, as well as lung and hepatic inflammation induced by MCYST-LR. A significant attenuation of hepatic injuries was observed for the first time. The authors declare that there are no conflicts of interest. The authors are grateful to Antonio
Carlos Quaresma and Diego Vinicius Ribeiro for their skillful technical assistance. This study was supported by: The Centers of Excellence click here Program (PRONEX/FAPERJ), The Brazilian Council for Scientific and Technological Florfenicol Development (CNPq), The Carlos Chagas Filho Rio de Janeiro State Research Supporting Foundation (FAPERJ). “
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accidents involving the spider Phoneutria nigriventer are frequent in Brazil. Among the early signs of poisoning, excruciating localized pain, sweating, and nausea are commonly reported, while penile erection is rare but have been reported especially among young victims ( Schenberg and Lima, 1966). Although priapism is a rare symptom in Phoneutria spider accidents, it can be consistently induced in mice under experimental conditions by injecting crude venom or the purified toxin Tx2-5 or Tx2-6. There is a clear dose-dependency and time-course and more important, it is the very first sign of intoxication so it can be induced in doses as low as to avoid other symptoms (described below). This strengthens the possibility of using Tx2-6 as a tool to manage erectile dysfunction or to investigate erectile mechanisms. Therefore, it is vital to understand the mechanisms by which Tx2-6 induces erection and the role of central and peripheral nervous system in this mechanism. On the other hand, in the event of a priapism in human patients, the knowledge of the mechanisms involved may also lead to a better treatment. Activity-driven purification identified two priapism-inducing peptide toxins characterized by mass spectrometry and peptide sequencing (Edman’s degradation) (Troncone et al., 1998 and Yonamine et al.