Effects of histaminergic agents in dorsal hippocampus, on retrieval memory deficts induced by scopolamine in an inhibitory avoidance test in rats

• Grant number: 06/06614-7
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2007
• End date: July 31, 2009
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Carla Christina Medalha
• Grantee: Carla Christina Medalha
• Host Institution: Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil

Abstract

Several evidences suggest that brain histamine is involved in learning and memory processes, but the actual contribution of the hippocampal histaminergic system to these processes remains controversial. The aim of the present study is to analyze the interaction between histaminergic activity in dorsal hippocampus and its effects on scopolamine induced memory deficit on inhibitory avoidance. For this purpose the animals will be trained for 10 days in an inhibitory avoidance paradigm. On the training days animals will be in a active avoidance box, with two compartments, black and white, separated by a sliding door. The animals will be placed in the white compartment and at the moment they go into the dark compartment, the door will be closed, and a footshock will be emitted for 5 seconds (0,2 mA; 40V). The latency will be recorded and this procedure repeated for 10 days, with a 24 h-interval between sections. After training phase, a retrieval test phase will be started, in a frequency of two times a week, for three weeks. On test days, animals will be bilaterally infused into dorsal hippocampus with scopolamine (5.0 µg/site), following the administration of clobenpropit (5.0 e 10.0 µg/site), a H3 receptor antagonist, and pyrilamine (0.5 e 1.0 µg/site), a H1 receptor antagonist. (AU)