Memory-enhancement effects of norepinephrine (NE) were investigated by infusing NE into the central amygdala (CEA) of Roman high-avoidance (RHA) and low-avoidance (RLA) rats after training on active and passive behaviors in the defensive-burying paradigm. During acquisition, both lines spent comparable time in burying behavior. RLA rats, but not RHA rats, also displayed substantial immobility. ...

PURPOSE To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. METHODS Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST). Immobility and number of stops were measured. RESULTS Rats given injections of fluoxetine displayed significantly less immobility (...

We examined the effects of minaprine and sulpiride injected into the medial amygdaloid nucleus on the duration of immobility in rats forced to swim. Minaprine (50 micrograms/microliter) significantly reduced the duration of immobility, while sulpiride (50 micrograms/microliters) remarkedly enhanced it. These results suggest that the medial amygdaloid nucleus might be involved in the suppressive...

The forced swim test in rodents has been widely used to evaluate potential effectiveness of antidepressant medications since it was described in 1977 by Porsolt. In this test, a rodent is placed in a water container, and its immobility time is measured. The immobility time indicates the level of inactivity, interpreted as ‘hopelessness’, and has been shown to decrease when the rodent is treated...

During early ontogeny, stimuli that pose a threat to an animal change. Unrelated adult male rats may kill young rats, but infanticide ends around weaning. Predation, on the other hand, may increase during early ontogeny when rats begin to extend their activity range. We investigated the developmental course of two defensive responses, immobility and analgesia, in young rats exposed to an adult ...