Poster 096 - Obtention, purification and isolation of vasoactive peptides from plasma of snake

Poster 96. Congresso da Sociedade Brasileira de Toxinologia, 8., Symposium of the Pan American Section of the International Society on Toxinology, 8., 2004, Angra dos Reis, Brasil. Abstracts... J. Venom. Anim. Toxins incl.Trop. Dis., 2004, 10, 3, p.455.

Obtention, Purification and Isolation of Vasoactive Peptides from Plasma of Snake Bothrops jararaca, snake Viperidae, Crotalinae.

1 Laboratório de Bioquímica e Biofisica, 2 Laboratorio de Farmacologia – Instituto Butantan – São Paulo – SP.

Objective: Obtention of the bradykinin peptide analogus of mammalian from plasma of snake Bothropsjararaca ( BJP), liberated through of enzymatic action for protease of type trypsin or similar to the action of the Bothropsjararaca venom (BJV), denominated kallikrein plasmatic. ( Rocha e Silva; 1973) The discovery of bradykinin on mammalian led to a new understanding of many physiologic pathological phenomena including circulatory shock induced by venoms and toxins. ( Hawgood et al;1997) The particularities of kallikrein-kinin system in reptile and birds suggest mechanism of adaptation from the action the toxins.

Methods: BJP was collect to treatment with trypsin ( protease), to be analyzed at assay of medium blood pressure of the snake Bothropsjararaca and rats wistar.

Results: The peptide liberated from BJP, analyzed at bioassay of rats wistar, demonstrated to be not important to hypotension activity. However, when it was analyzed to verify the potenciation effect of the bradykinin, inhibiting the ACE (angiotensin - converting enzyme), we obtained a signification action.

Conclusion: Bothropsjararaca venom (BJV) caused a fall in the carotid artery blood pressure of the anaesthetized snake. This effect was tachyphylactic and was potentiated by captopril, a kininase II inhibitor; it was partially antagonized by promethazine plus cimetidine and was not affected by atropine. Similar hypotensive effects were obtained by administration of trypsin or a partially purified BJV kininogenase to the snake. Incubation of Bothropsjararaca plasma (BJP) with trypsin released a substance (or substances) that produced hypotension in the snake but not in the rat; this hypotensive effect was also potentiated by captopril. ( Prezoto e cols; 1989) These data also suggest that the snake Bothropsjararaca, like birds, may have developed its own kallikrein-kinin system.