Data/hora: 01/06/2024 07:38:09

Provedor de dados: 	56	
País: 	Brazil	
Título: 	L-histidine enhances learning in stressed zebrafish	
Autores: 	Cofiel,L.P.V.; Mattioli,R.	
Data: 	2009-01-01	
Ano: 	2009	
Palavras-chave: 	Danio rerio; Conditioning; Feed trial; Thioperamide; H3 receptor; Blood glucose.	
Resumo: 	The aim of the present study was to determine the effect of the histaminergic precursor L-histidine and the H3 receptor antagonist thioperamide on the learning process of zebrafish submitted or not to confinement stress. On each of the 5 consecutive days of experiment (D1, D2, D3, D4, D5), animals had to associate an interruption of the aquarium air supply with food offering. Non-stressed zebrafish received an intraperitoneal injection of 100 mg/kg L-histidine, 10 mg/kg thioperamide or saline after training. Stressed animals received drug treatment and then were submitted to confinement stress for 1 h before the learning procedure. Time to approach the feeder was measured (in seconds) and was considered to be indicative of learning. A decrease in time to approach the feeder was observed in the saline-treated group (D1 = 141.92 ± 13.57; D3 = 55 ± 13.54), indicating learning. A delay in learning of stressed animals treated with saline was observed (D1 = 217.5 ± 25.66). L-histidine facilitated learning in stressed (D1 = 118.68 ± 13.9; D2 = 45.88 ± 8.2) and non-stressed (D1 = 151.11 ± 19.20; D5 = 62 ± 14.68) animals. Thioperamide inhibited learning in non-stressed (D1 = 110.38 ± 9.49; D4 = 58.79 ± 16.83) and stressed animals (D1 = 167.3 ± 26.39; D5 = 172.15 ± 27.35). L-histidine prevented the increase in blood glucose after one session of confinement (L-histidine = 65.88 ± 4.50; control = 53 ± 3.50 mg/dL). These results suggest that the histaminergic system enhances learning and modulates stress responses in zebrafish.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000100018	
Editor: 	Associação Brasileira de Divulgação Científica	
Relação: 	10.1590/S0100-879X2009000100018	
Formato: 	text/html	
Fonte: 	Brazilian Journal of Medical and Biological Research  v.42 n.1 2009	
Fonte: 	info:eu-repo/semantics/openAccess