Data/hora: 14/06/2024 05:16:29

Biblioteca(s): 	Embrapa Caprinos e Ovinos.	
Data corrente: 	04/10/2011	
Data da última atualização: 	23/09/2019	
Autoria: 	SALLES, H. O.; VASCONCELOS, I. M.; SANTOS, L. F. L.; OLIVEIRA, H. D.; COSTA, P. P. C.; NASCIMENTO, N. R. F.; SANTOS, C. F.; SOUSA, D. F.; JORGE, A. R. C.; MENEZES, D. B.; MONTEIRO, H. S. A.; GONDIM, D. M. F.; OLIVEIRA, J. T. A.	
Afiliação: 	HEVILA OLIVEIRA SALLES FIGUEIREDO, CNPC; Universidade Federal do Ceará (UFC), Fortaleza, CE.; Universidade Estadual do Ceará (UECe) - Fortaleza, CE.; UECe; UECe; UECe; UECe; UFC, Fortaleza, CE.; UFC; UFC; UFC; UFC; UFC.	
Título: 	Towards a better understanding of Ipomoea asarifolia toxicity: evidence of the involvement of a leaf lectin.	
Ano de publicação: 	2011	
Fonte/Imprenta: 	Toxicon, v. 58, p. 502-508, 2011.	
DOI: 	10.1016/j.toxicon.2011.08.011	
Idioma: 	Inglês	
Conteúdo: 	Abstract: Natural intoxication of livestock by ingestion of Ipomoea asarifolia leaves has been reported to occur widely in Brazil. Previous studies carried out by our research group provided strong evidence that a lectin could be involved with the toxic properties of I. asarifolia.To reinforce this hypothesis, a lectin-enriched fraction (LEF) was isolated from I. asarifolia leaves and its toxic effects were assessed. Leaves of I. asarifolia were excised from plants growing widely in the ?eld, mechanically wounded and maintained in a chamber at 25 3 C for 72 h in the dark, under near 100% relative humidity. The leaf proteins were extracted, ammonium sulfate precipitated, chromatographed on DEAE-cellulose and Phenyl-Sepharose to produce LEF that under SDS?PAGE showed a molecular mass of 44.0 kDa and after N-terminal amino acid analysis a primary sequence composed of AGYTPVLDIGAEVLAAGEPY. The in vivo toxicity of LEF assessed by intraorbital injection in mice showed induced severe uncoordinated movements without death. LEF reduced the muscular contraction in a dose depend way and at 29.8 mg/mL (CE50) it produces 50% inhibition of contraction, suggesting that LEF blunts autonomic neurotransmission. Isolated rat kidneys were perfused with LEF and no effects on the perfusion pressure or renal vascular resistance were observed, but urinary ?ow and glomerular ?ltration rate increased. Moreover, the percentage of tubular transport of Naþ,Kþ and Cl decreased. Histological examination of the kidneys perfused with LEF exhibited little alterations. These toxic effects observed above were concomitant with the increase of LEF hemag-glutination activity, which strongly suggest that one of the toxic principles of I. asarifolia is a lectin present in its leaves.	
Palavras-Chave: 	Ipomoea asarifolia; Lectin; Sulato de amônia.	
Thesagro: 	Erva daninha; Lectina; Planta tóxica; Salsa; Toxidez.	
Thesaurus Nal: 	toxicity.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Caprinos e Ovinos (CNPC)	
Exemplares: 	CNPC - (24654-1) - UPC - AP - DD -  -  -  - DIS