Contribution of Lymphocytes in Edema Induced by Venom from the Wasp (Belonogaster fuscipennis)

Abstract

Subplantar injection of Belonogaster fuscipennis crude venom (40 µg/paw) induced rat hind-paw edema. The edema was slow in onset and reached maximum size in the fifth hr after injection of the venom. In amethopterin-induced leucopenic rats, the edematogenic response to the venom (40 µg/paw) was significantly reduced. Lymphocytes suspension given i.v. to another group of leucopenic rats caused a reversal of this response, but neutrophils suspension failed to reduce the response. In animals rendered lymphocytopenic by experimental obstruction of the thoracic duct, the oedema-forming activity of the venom was also markedly reduced. From these results, we suggest that the circulating lymphocytes participate in B. fuscipennis venom-induced edema.