background sildenafil (viagra) has been introduced to treat erectile dysfunction by acting as phosphodiesterase 5 inhibitor and hence accumulation of guanosine cyclic monophosphate (cgmp). on the other hands, the nitric oxide/cgmp signaling pathway has crucial role in synaptic plasticity processes like long-term potentiation (ltp) in the central nervous system considered as a model of learning ...

objective: strong evidence indicate that activity of glucocorticoid receptors is necessary for emotional memory processess and these effects probably are mediated by hipppocampal opioid receptors. the aim of this study was to test whether there were any interaction between glucocorticoid and hippocampal opiate receptors on consolidtaion and retrieval of spatial memory. materials and methods: in...

there is strong evidence that two cerebral hemispheres are differentially involved in emotional memory and that amygdala is a key subcortical structure for emotional experience. the present research investigated the possible involvement of lateralization of basolateral amygdala (bla) and central amygdala (cea) in place avoidance memory. for this purpose, male long-evans rats (280-320 g) were im...

background: testosterone and its metabolites have important roles in learning and memory. the current study has conducted to assess the effect of pre-training, post-training and pre-probe trial intrahippocampal ca1 administration of 3 alpha-anderostanediol (one of the metabolites of testosterone) and indomethacin (as 3 alpha-hydroxysteroid dehydrogenase enzyme blocker) on acquisition, consolida...

There is strong evidence that two cerebral hemispheres are differentially involved in emotional memory and that amygdala is a key subcortical structure for emotional experience. The present research investigated the possible involvement of lateralization of basolateral amygdala (BLA) and central amygdala (CEA) in place avoidance memory. For this purpose, male Long-Evans rats (280-320 g) were im...

Background: Testosterone and its metabolites have important roles in learning and memory. The current study has conducted to assess the effect of pre-training, post-training and pre-probe trial intrahippocampal CA1 administration of 3 alpha-anderostanediol (one of the metabolites of testosterone) and indomethacin (as 3 alpha-hydroxysteroid dehydrogenase enzyme blocker) on acquisition, consolida...

It has been shown that brain glucose metabolism impairment, obesity, and diabetes couldlead to cognitive decline and Alzheimer’s disease (AD) pathogenesis. Kisspeptin (KP) a G-proteincoupled receptor neuropeptide, has been suggested as a link between energy balance andreproduction. Some studies have shown that the attenuation of KP signaling decreases metabolismand energ...

objective(s): due to the prevalence and pervasiveness of stress in modern life and exposure to both chronic and acute stresses, it is not clear whether prior exposure to chronic stress can influence the impairing effects of acute stress on memory retrieval. this issue was tested in this study. materials and methods: adult male wistar rats were randomly assigned to the following groups: control,...