Isolation of a haemorrhagic protein toxin (SA-HT) from the Indian venomous butterfish (<i>Scatophagus argus, </i>Linn) sting extract

Abstract

A haemorrhagic protein toxin (SA-HT) was isolated and purified from the spine extract of the Indian venomous butterfish, <i>S</i>. <i>argus </i>Linn, by two step ion exchange chromatography. The toxin was homogeneous in native and SDS-PAGE gel. SDS-molecular weight of the toxin was found to be 18.1± 0.09 kDa. SA-HT produced severe haemorrhage on stomach wall

but devoid of cutaneous haemorrhage. UV, EDTA, trypsin, protease, cyproheptadine, indomethacin, acetylsalicylic acid and BW755C treatment significantly antagonized the haemorrhagic activity of SA-HT. The toxin produced dose and time dependent oedema on mice hind paw, which was significantly encountered by cyproheptadine, indomethacin and BW755C. SA-HT increased capillary permeability on guineapig dorsal flank. On isolated guineapig ileum, rat fundus and uterus. SAHT produced slow contraction which was completely antagonised by prostaglandin blocker SC19220. On isolated rat duodenum,

SA-HT produced slow relaxation. SA-HT significantly increased plasma plasmin, serum MDA level and decreased serum SOD level indicating the possible involvement of cyclooxygenase and lipooxygenase pathway.