The present study assesses the involvement of the supramammillary and adjacent nuclei in spatial memory and anxiety-like behaviors. Rats with electrolytic lesions in the supramammillary nucleus were pre- and post-operatively trained in two spatial memory tasks and two anxiety tasks. Spatial memory tasks were performed in an open field with seven different goal positions containing the reward. A...

introduction: there are evidences showing the role of nitric oxide in the opiate reward properties. the role of nitric oxide signaling pathway as an intracellular mechanism on augmentation of long term potentiation in hippocampal ca1 area of rats is also confirmed. it has been also reported that oral morphine dependence facilitates formation of spatial learning and memory via activation of nmda...

logic substrate of learning and spatial memory (Jarrad, Okaichi, Steward & Goldschmidt; 1984; Morris, Schenk, Tweedie & Jarrad, 1990; Neave, Nagle & Aggleton, 1997; O ́Keefe & Nadel, 1978; Olton & Papas, 1979; Olton, 1978; García-Moreno, Santín, Rubio, García & Arias, 1993; Santín, Rubio, Begega & Arias, 1999a; Santín, Rubio, Begega & Arias, 1999b). Following the works by Olton and collegues (Ol...

Corticosterone (CORT), the predominant glucocorticoid in rodents, elevated for 21 days damages hippocampal subregion CA3. We tested the hypothesis that CORT would impair spatial memory, a hippocampal function. In each of the three experiments, rats received daily, subcutaneous injections of either CORT (26.8 mg/kg body weight in sesame oil) or sesame oil vehicle alone (VEH). CORT given for 21 o...

Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and distinct distribution in the hippocampus, a brain region which is directly involved in the regul...

Introduction: Ethanol can induce a wide spectrum of neurophysiological effects via interaction with multiple neurotransmitter systems and disruption of the balances between inhibitory and excitatory neurotransmitters. Prefrontal cortex is involved in cognitive process including working memory and is sensitive to ethanol. Present study investigates the effects of intraperitoneal (i.p.) admini...

introduction: it has been reported that acute administration of morphine impairs learning and memory processes in rats. furthermore, recent studies showed that saffron extract improved ethanol-induced impairments of learning behaviors in mice, and also prevented ethanol-induced inhibition of hippocampal long-term potentiation. it can be postulated that there are some common mechanisms responsib...

introduction: ascorbic acid (aa) acts as an antioxidant in the central nervous system (cns) of the mammalians. it is released from the some nerve ending together with neurotransmitters. the results have shown that ascorbic acid could affect learning as well as memory. in this study, we examined the effect of icv injection of ascorbic acid on learning and memory by morris water maze. method: in ...

introduction: the n-methyl-d-aspartate (nmda) receptors, which have been implicated in memory formation, could be noncompetitively blocked by ketamine. the present study examines the short term effect of ketamine on induction of anterograde and retrograde amnesia in male rats using morris water maze (mwm). methods: male n-mri rats were randomly divided into nine experimental groups. mwm studies...