Impairment in the acquisition of passive and active avoidance learning tasks due to bilateral entorhinal cortex lesions

Memory improvement in ibotenic acid induced model rats by extracts of Scutellaria baicalensis

“…The cholinergic pathway is well known for its role on learning and memory in the mammalian limbic system (Amaral and Kurz, 1985;Ueki et al, 1994;Shinjo et al, 1998). Therefore, we first focused on the hippocampal cholinergic systems and found an increased number of hippocampal cholinergic cells, compared to the vehicle administered control group of the Ibo model.…”

“…Because many reports have shown that the hippocampus and entorhinal cortex is the region where loss of neurons and synapses occurred in early AD (Jensen et al, 1994;Ueki et al, 1997), we used a modified rat model which was primarily designed to induce degeneration of hippocampal neurons by injecting ibotenic acid into the entorhinal cortex (Ueki et al, 1994;Park et al, 2000).…”

“…The surgery protocol was followed as described with modifications (Ueki et al, 1994;Park et al, 2000). The rats were anesthetized with equithensin (350 mM sodium pentobarbital, 250 mM chloral hydrate, 85 mM MgSO 4 , 40% prophylene glycol in 10% ethanol, 2 ml/kg).…”

“…Among the many underlying reasons for the memory impairment, cholinergic system defects in the cortical and the hippocampal areas have been identified as one of the major causes of these abnormal behaviors (Ueki et al, 1994;Shinjo et al, 1998;Park et al, 2000). For this reason, much research has been focused on chemical reagents that can protect the cholinergic system; some have found use as therapeutic reagents (Giacobini, 1997).…”

Recovery from Lesion‐Associated Learning Deficits by Fetal Amygdala Transplants

“…Active avoidance: The procedure reported by Ueki et al (1994) was used in the present study to train the rats on the AA task. On the 1st day of the experiment, the rat was allowed to explore the box for 5 rain.…”