| Journal: | The journal of venomous animals and toxins including tropical diseases |
| Database: | PERIÓDICA |
| System number: | 000298814 |
| ISSN: | 1678-9199 |
| Authors: | Cecchini, A.L1 Soares, A.M2 Giglio, J.R3 Amara, S4 Arantes, E.C |
| Institutions: | 1Universidade de Sao Paulo, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Ribeirao Preto, Sao Paulo. Brasil 2Universidade de Ribeirao Preto, Unidade de Biotecnologia, Ribeirao Preto, Sao Paulo. Brasil 3Universidade de Sao Paulo, Faculdade de Medicina de Ribeirao Preto, Ribeirao Preto, Sao Paulo. Brasil 4Oregon Health Sciences University, Vollum Institute, Portland, Oregon. Estados Unidos de América |
| Year: | 2004 |
| Volumen: | 10 |
| Number: | 3 |
| Pages: | 260-279 |
| Country: | Brasil |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Experimental, aplicado |
| English abstract | This paper describes a brief study on the crotoxin mechanism of action, regarding the transport of GABA and L-glutamate in rats cortico-cerebral synaptosomes and in heterologous systems, such as COS-7 cells expressing gabaergic transporters, and C6 glioma cells and Xenopus oocytes expressing glutamatergic transporters. Crotoxin concentrations over 1 µM caused an inhibitory effect of ³H-L-glutamate and ³H-GABA, and reversibly inhibited L-glutamate uptake by C6 glioma cells. When COS-7 cells were assayed, no inhibition of the ³H-GABA transport could be evidenced. Crotoxin kept its inhibitory effect on neurotransmitters uptake even when Ca2+ ions were removed from the medium, therefore, independently of its PLA2 activity. In addition, high concentrations (2 mM) of BPB did not avoid the action of crotoxin on the neurotransmitters uptake. Crotoxin also inhibited ³H-L-glutamate, independently on Na+ channel blockade by TTX. In addition, an evaluation of the lactic dehydrogenase activity indicated that uptake inhibition does not involve a hydrolytic action of crotoxin upon the membrane. We may also suggest that crotoxin acts, at least partially, altering the electrogenic equilibrium, as evidenced by confocal microscopy, when a fluorescent probe was used to verify cell permeability on C6 glioma cells in presence of crotoxin |
| Disciplines: | Biología |
| Keyword: | Reptiles, Bioquímica, Veneno de víbora, Crotoxina, Mecanismo de acción, Glutamato, GABA, Crotalus durissus terrificus, Viperidae |
| Keyword: | Biology, Reptiles, Biochemistry, Snake venom, Crotoxin, Action mechanism, Glutamate, GABA, Crotalus durissus terrificus, Viperidae |
| Full text: | Texto completo (Ver HTML) |
