Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum
Sea anemones are a rich source of biologically active substances. In crayfish muscle fibers, Bunodosoma cangicum whole venom selectively blocks the I K(Ca) currents. In the present study, we report for the first time powerful hemolytic and neuroactive effects present in two different fractions obtai...
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| Format: | Article |
| Language: | English |
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Associação Brasileira de Divulgação Científica
2001-07-01
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| Series: | Brazilian Journal of Medical and Biological Research |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000700009 |
| _version_ | 1831519530596171776 |
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| author | P. Lagos R. Duran C. Cerveñansky J.C. Freitas R. Silveira |
| author_facet | P. Lagos R. Duran C. Cerveñansky J.C. Freitas R. Silveira |
| author_sort | P. Lagos |
| collection | DOAJ |
| description | Sea anemones are a rich source of biologically active substances. In crayfish muscle fibers, Bunodosoma cangicum whole venom selectively blocks the I K(Ca) currents. In the present study, we report for the first time powerful hemolytic and neuroactive effects present in two different fractions obtained by gel-filtration chromatography from whole venom of B. cangicum. A cytolytic fraction (Bcg-2) with components of molecular mass ranging from 8 to 18 kDa elicited hemolysis of mouse erythrocytes with an EC50 = 14 µg/ml and a maximum dose of 22 µg/ml. The effects of the neuroactive fraction, Bcg-3 (2 to 5 kDa), were studied on isolated crab nerves. This fraction prolonged the compound action potentials by increasing their duration and rise time in a dose-dependent manner. This effect was evident after the washout of the preparation, suggesting the existence of a reversible substance that was initially masking the effects of an irreversible one. In order to elucidate the target of Bcg-3 action, the fraction was applied to a tetraethylammonium-pretreated preparation. An additional increase in action potential duration was observed, suggesting a blockade of a different population of K+ channels or of tetraethylammonium-insensitive channels. Also, tetrodotoxin could not block the action potentials in a Bcg-3-pretreated preparation, suggesting a possible interaction of Bcg-3 with Na+ channels. The present data suggest that B. cangicum venom contains at least two bioactive fractions whose activity on cell membranes seems to differ from the I K(Ca) blockade described previously. |
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| id | doaj.art-5316002144444489a308ecc3cdaecaf7 |
| institution | Directory Open Access Journal |
| issn | 0100-879X 1414-431X |
| language | English |
| last_indexed | 2024-12-13T17:16:49Z |
| publishDate | 2001-07-01 |
| publisher | Associação Brasileira de Divulgação Científica |
| record_format | Article |
| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-5316002144444489a308ecc3cdaecaf72022-12-21T23:37:25ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research0100-879X1414-431X2001-07-0134789590210.1590/S0100-879X2001000700009Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicumP. LagosR. DuranC. CerveñanskyJ.C. FreitasR. SilveiraSea anemones are a rich source of biologically active substances. In crayfish muscle fibers, Bunodosoma cangicum whole venom selectively blocks the I K(Ca) currents. In the present study, we report for the first time powerful hemolytic and neuroactive effects present in two different fractions obtained by gel-filtration chromatography from whole venom of B. cangicum. A cytolytic fraction (Bcg-2) with components of molecular mass ranging from 8 to 18 kDa elicited hemolysis of mouse erythrocytes with an EC50 = 14 µg/ml and a maximum dose of 22 µg/ml. The effects of the neuroactive fraction, Bcg-3 (2 to 5 kDa), were studied on isolated crab nerves. This fraction prolonged the compound action potentials by increasing their duration and rise time in a dose-dependent manner. This effect was evident after the washout of the preparation, suggesting the existence of a reversible substance that was initially masking the effects of an irreversible one. In order to elucidate the target of Bcg-3 action, the fraction was applied to a tetraethylammonium-pretreated preparation. An additional increase in action potential duration was observed, suggesting a blockade of a different population of K+ channels or of tetraethylammonium-insensitive channels. Also, tetrodotoxin could not block the action potentials in a Bcg-3-pretreated preparation, suggesting a possible interaction of Bcg-3 with Na+ channels. The present data suggest that B. cangicum venom contains at least two bioactive fractions whose activity on cell membranes seems to differ from the I K(Ca) blockade described previously.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000700009Bunodosoma cangicumsea anemonehemolytic activityneurotoxinscrab nerve |
| spellingShingle | P. Lagos R. Duran C. Cerveñansky J.C. Freitas R. Silveira Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum Brazilian Journal of Medical and Biological Research Bunodosoma cangicum sea anemone hemolytic activity neurotoxins crab nerve |
| title | Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum |
| title_full | Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum |
| title_fullStr | Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum |
| title_full_unstemmed | Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum |
| title_short | Identification of hemolytic and neuroactive fractions in the venom of the sea anemone Bunodosoma cangicum |
| title_sort | identification of hemolytic and neuroactive fractions in the venom of the sea anemone bunodosoma cangicum |
| topic | Bunodosoma cangicum sea anemone hemolytic activity neurotoxins crab nerve |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000700009 |
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