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.

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.

Scorpions from Mata do Buraquinho, João Pessoa, Paraíba, Brazil, with ecological notes on a population of Ananteris mauryi Lourenço (Scorpiones, Buthidae)

Four species of scorpions (Ananteris mauryi Lourenço, 1982, Tityus neglectus Mello-Leitão, 1932, T. pusillus Pocock, 1893 and T. stigmurus (Thorell, 1876)) were collected in the "Mata do Buraquinho", João Pessoa, state of Paraíba, Brazil. Aspects of biology for A. mauryi and new records on the geographic distribution of other species were annotated. Notes on the abundance and sex ratio on A. mauryi, the most abundant species in the area, are presented and discussed.

Maintenance of scorpions of the genus Tityus koch (Scorpiones, Buthidae) for venom obtention at Instituto Butantan, São Paulo, Brazil

This work presents the experience of the Laboratory of Arthropods at Instituto Butantan, wich maintains scorpions in captivity in order to obtain the venom used in the production of anti-arachnid serum. Between 1993 and 2000, the laboratory received 24.781 specimens of Tityus serrulatus in order to obtain poison for the production of anti-scorpion serum. In the first extraction, performed by electrical stimulation, the animals gave an average quantity of 0.4 mg venom per specimen. Animal acquisition and involved professional safety are considered. In addition, the captivity, handling and feeding techniques are described, as well as the method and equipment used for venom extraction. It shows the importance of regular campaigns, offering information to the general population in order to motivate these to catch and send alive scorpions to the Institute to assuring a regular entrance of scorpions.

Evolution of scorpionism by Tityus bahiensis (Perty) and Tityus serrulatus Lutz and Mello and geographical distribution of the two species in the state of Säo Paulo - Brazil

Two scorpion species of medical importance occur in the state of Säo Paulo the native brown scorpion Tityus bahiensis (Perty) and the highly toxic yellow scorpion Tityus serrulatus Lutz and Mello, which was brought into the state. The study of accident data of patients admitted to the Vital Brazil Hospital of the Butantan Institute from 1982 to 1993 revealed a gradual increase in stings by T. serrulatus in contrast to those by T. bahiensis which a variation from 5.2 per cent to 29.7 per cent. Also, an inventory of the scorpions sent to the Laboratory of Venomous Arthropods of the Butantan Institute over the same period showed an expressive growth in the number of T. serrulatus specimens in contrast to that of T. bahiensis. These data suggest a significative proliferation of T. serrulatus in the state of Säo Paulo over the past 12 years, and a probable interspecific competition between T. serrulatus and the endemic T. bahiensis. The analysis of scorpion accidents reported to the state of Säo Paulo Health Department (Secretaria de Estado da Saúde de Säo Paulo) corroborated the higher severity of T.serrulatus envenoming. The results pointed to the possibility of an increase in severe envenoming and deaths by scorpion stings in the state of Säo Paulo. Aiming to contribute to scorpion prevention and control programs, the present geographical distribution of both dangerous species was mapped, pointing to the areas of higher risk of scorpionism in the state.